This study examined the effects of long-term estradiol supplementation on neuropeptide Y (NPY) neurotransmission in skeletal muscle resistance vessels. First-order arterioles from the red gastrocnemius muscle of ovariectomized female rats with or without estradiol supplementation were studied. The results showed that NPY induced moderate vasoconstriction, and its enzymatic breakdown by dipeptidyl peptidase IV was active in these vessels. However, long-term estradiol supplementation did not influence NPY-mediated vasoconstriction, NPY overflow following stimulation, or its degradation, suggesting estradiol does not directly modulate NPY neurotransmission in skeletal muscle resistance arterio
This study examined the relationship between estrogen and interleukin-6 (IL-6) levels in 43 postmenopausal women with osteoarthritis and 20 control postmenopausal women. The study found that IL-6 levels were significantly higher in osteoarthritis patients compared to controls, and estrogen levels were significantly lower. There was a minimal inverse correlation found between IL-6 and estrogen levels in osteoarthritis patients. The results suggest that estrogen deficiency after menopause may cause alterations in IL-6 levels in postmenopausal women with osteoarthritis.
circadian rhythm in Spinal cord injuriesGhizal Fatima
The document summarizes a study that evaluated oxidative stress and antioxidant parameters in patients with spinal cord injuries (SCI) and their relationship to pain symptoms. The study found that SCI patients had significantly higher levels of lipid peroxides and protein carbonyl groups, indicating greater oxidative stress, compared to healthy controls. SCI patients also had lower levels of the antioxidant enzymes catalase, glutathione peroxidase, and glutathione reductase. Additionally, oxidative stress markers correlated more strongly with pain symptoms in SCI patients than in controls. The results suggest that increased oxidative stress may contribute to the pathogenesis and symptoms of SCI.
Xuhui Liu is an experienced physician-scientist specializing in biomedical research. He has over 20 years of experience conducting clinical and preclinical research focused on musculoskeletal and neurological diseases. Currently, he is an Associate Professor at UCSF leading multiple research programs investigating bone regeneration, rotator cuff injuries, and neuro-musculoskeletal trauma. He has published extensively in peer-reviewed journals and serves as a reviewer for several orthopedic research publications.
Xuhui Liu is an experienced physician-scientist specializing in biomedical research. He has over 20 years of experience conducting clinical and preclinical research focused on musculoskeletal and neurological diseases. Currently, he is an Associate Professor at UCSF leading research programs in bone health, rotator cuff injuries, and neuro-musculoskeletal trauma. He has published over 30 peer-reviewed papers and is an active reviewer for several academic journals.
This document summarizes the results of a clinical trial investigating the efficacy of oral low molecular weight hyaluronic acid (HA) in improving symptoms and function in patients with knee osteoarthritis. The study was a randomized, double-blind, placebo-controlled trial involving Taiwanese patients with knee OA. Patients received either an oral liquid containing low molecular weight HA, glucosamine, and chondroitin, or a placebo daily for 8 weeks. Outcome measures including the WOMAC scale and SF-36 questionnaire showed significant improvements in pain, physical function, and quality of life in the HA group compared to the placebo group. The study demonstrated oral low molecular HA was effective in relieving symptoms of mild knee O
A randomized controlled_trial_of_four_doses_of_transdermal_estradiol_for_prev...manelle gutierrez
This randomized controlled trial tested the effects of four doses of transdermal estradiol (0.025 mg/day, 0.05 mg/day, 0.06 mg/day, and 0.1 mg/day) on preventing bone loss in postmenopausal women compared to a placebo. At 24 months, all doses of estradiol resulted in statistically significant increases in bone mineral density at the spine and hip compared to decreases seen with placebo. The lowest dose of 0.025 mg/day increased spine bone mineral density by 2.37% and hip bone mineral density by 0.26% compared to decreases of 2.49% and 2.04% respectively with placebo. This study demonstrates that even the
This document discusses the use of platelet-rich plasma (PRP), viscosupplementation, and stem cells in the treatment of musculoskeletal diseases. PRP contains growth factors that promote healing and reduce inflammation. Studies show PRP reduces pain and improves function in tendinopathies, osteoarthritis, and other joint injuries. Combining PRP with hyaluronic acid or stem cells provides an enhanced treatment approach by addressing the three components of tissue engineering: growth factors, cells, and scaffolding. Autologous stem cell therapy with decompression has shown promise for treating early-stage osteonecrosis of the femoral head. The document advocates using regenerative medicine techniques like PRP, scaffolds, and one's own stem cells as a
This document discusses the role of various factors in neurodegenerative diseases such as Amyotrophic lateral sclerosis (ALS), Alzheimer's disease, and Parkinson's disease. It notes that geographic clusters of ALS have been observed in areas such as Guam and Japan. It also discusses the metabolic cooperation between neurons and astrocytes in the brain, highlighting how disruptions to this interaction can lead to neurodegenerative disorders. The document reviews literature on various pathogenic mechanisms and potential environmental and genetic risk factors involved in these conditions.
This study examined the relationship between estrogen and interleukin-6 (IL-6) levels in 43 postmenopausal women with osteoarthritis and 20 control postmenopausal women. The study found that IL-6 levels were significantly higher in osteoarthritis patients compared to controls, and estrogen levels were significantly lower. There was a minimal inverse correlation found between IL-6 and estrogen levels in osteoarthritis patients. The results suggest that estrogen deficiency after menopause may cause alterations in IL-6 levels in postmenopausal women with osteoarthritis.
circadian rhythm in Spinal cord injuriesGhizal Fatima
The document summarizes a study that evaluated oxidative stress and antioxidant parameters in patients with spinal cord injuries (SCI) and their relationship to pain symptoms. The study found that SCI patients had significantly higher levels of lipid peroxides and protein carbonyl groups, indicating greater oxidative stress, compared to healthy controls. SCI patients also had lower levels of the antioxidant enzymes catalase, glutathione peroxidase, and glutathione reductase. Additionally, oxidative stress markers correlated more strongly with pain symptoms in SCI patients than in controls. The results suggest that increased oxidative stress may contribute to the pathogenesis and symptoms of SCI.
Xuhui Liu is an experienced physician-scientist specializing in biomedical research. He has over 20 years of experience conducting clinical and preclinical research focused on musculoskeletal and neurological diseases. Currently, he is an Associate Professor at UCSF leading multiple research programs investigating bone regeneration, rotator cuff injuries, and neuro-musculoskeletal trauma. He has published extensively in peer-reviewed journals and serves as a reviewer for several orthopedic research publications.
Xuhui Liu is an experienced physician-scientist specializing in biomedical research. He has over 20 years of experience conducting clinical and preclinical research focused on musculoskeletal and neurological diseases. Currently, he is an Associate Professor at UCSF leading research programs in bone health, rotator cuff injuries, and neuro-musculoskeletal trauma. He has published over 30 peer-reviewed papers and is an active reviewer for several academic journals.
This document summarizes the results of a clinical trial investigating the efficacy of oral low molecular weight hyaluronic acid (HA) in improving symptoms and function in patients with knee osteoarthritis. The study was a randomized, double-blind, placebo-controlled trial involving Taiwanese patients with knee OA. Patients received either an oral liquid containing low molecular weight HA, glucosamine, and chondroitin, or a placebo daily for 8 weeks. Outcome measures including the WOMAC scale and SF-36 questionnaire showed significant improvements in pain, physical function, and quality of life in the HA group compared to the placebo group. The study demonstrated oral low molecular HA was effective in relieving symptoms of mild knee O
A randomized controlled_trial_of_four_doses_of_transdermal_estradiol_for_prev...manelle gutierrez
This randomized controlled trial tested the effects of four doses of transdermal estradiol (0.025 mg/day, 0.05 mg/day, 0.06 mg/day, and 0.1 mg/day) on preventing bone loss in postmenopausal women compared to a placebo. At 24 months, all doses of estradiol resulted in statistically significant increases in bone mineral density at the spine and hip compared to decreases seen with placebo. The lowest dose of 0.025 mg/day increased spine bone mineral density by 2.37% and hip bone mineral density by 0.26% compared to decreases of 2.49% and 2.04% respectively with placebo. This study demonstrates that even the
This document discusses the use of platelet-rich plasma (PRP), viscosupplementation, and stem cells in the treatment of musculoskeletal diseases. PRP contains growth factors that promote healing and reduce inflammation. Studies show PRP reduces pain and improves function in tendinopathies, osteoarthritis, and other joint injuries. Combining PRP with hyaluronic acid or stem cells provides an enhanced treatment approach by addressing the three components of tissue engineering: growth factors, cells, and scaffolding. Autologous stem cell therapy with decompression has shown promise for treating early-stage osteonecrosis of the femoral head. The document advocates using regenerative medicine techniques like PRP, scaffolds, and one's own stem cells as a
This document discusses the role of various factors in neurodegenerative diseases such as Amyotrophic lateral sclerosis (ALS), Alzheimer's disease, and Parkinson's disease. It notes that geographic clusters of ALS have been observed in areas such as Guam and Japan. It also discusses the metabolic cooperation between neurons and astrocytes in the brain, highlighting how disruptions to this interaction can lead to neurodegenerative disorders. The document reviews literature on various pathogenic mechanisms and potential environmental and genetic risk factors involved in these conditions.
Liver ischemia/reperfusion injury, a setting in which the functional mass is ...Prof. Hesham N. Mustafa
The document discusses a study on the effects of the phosphodiesterase type-5 (PDE5) inhibitor tadalafil on liver ischemia/reperfusion injury in rats. The study found that tadalafil treatment before ischemia/reperfusion injury helped restore normal liver enzyme levels, reduced oxidative stress and inflammation in liver tissue, and decreased levels of tumor necrosis factor-alpha, interleukin-6, and intercellular adhesion molecule-1. Histological analysis also showed tadalafil treatment helped protect against liver damage. The findings suggest that modulating the inflammatory response may be one mechanism by which tadalafil provides hepatoprotection against ischemia/reperfusion injury.
39689944 Age Loc Vitality Ingredient Vtudies[1]Laura Fallon
This study examined the effects of Cordyceps sinensis Cs-4 supplementation on age-related changes in the expression of mitochondrial genes in mouse skeletal muscle and brain tissue. The researchers identified 393 genes related to mitochondria that changed expression with age in these tissues. Cs-4 supplementation opposed age-related changes in 52 of these genes, with 92% changing in a direction associated with younger gene expression. Analysis also showed Cs-4 impacted several gene pathways associated with aging in muscle tissue. The results provide evidence that Cs-4 can modulate aging effects at the transcriptional level in muscles and brain.
Am j physiol heart circ physiol 2000-matsubara-h1534-9Natasha Xavier
This document reports on a study investigating the influence of myocardial collagen content on rat papillary muscle function. Three groups of rats were studied: 1) a renal hypertension group with increased collagen (RHTR), 2) a group with decreased collagen through glutathione infusion (GSSG), and 3) untreated controls. The main findings were:
1) GSSG rats had increased active stiffness and myocyte size compared to controls, suggesting decreased collagen is related to hypertrophy and increased active stiffness.
2) Passive tension-length curves were shifted down in GSSG rats, indicating decreased passive stiffness, and up in RHTR rats, indicating increased passive stiffness.
3) Changes in collagen content bidirectionally influence
Viscosupplementation, PRP Steroids-Consensus in OA-Dr. M.S.DhillonTheRightDoctors
The document discusses different injection treatments for osteoarthritis (OA), including corticosteroids, hyaluronic acid injections, and platelet-rich plasma (PRP). It provides an overview of the mechanisms of action and evidence for each treatment. For PRP specifically, it summarizes that PRP is safe for treating OA and can provide symptomatic relief for up to 3 months, though more research is still needed to determine optimal formulations and treatment protocols.
This study investigated gait and balance in patients with Chronic Fatigue Syndrome (CFS) compared to healthy sedentary controls. 11 CFS patients and 11 matched controls performed balance and gait tests before and after a 15-minute sub-anaerobic exercise test on a bicycle ergometer. Results showed no significant differences in postural sway between groups before or after exercise. However, several gait parameters were significantly different between CFS patients and controls, confirming reports of gait abnormalities in CFS patients. These gait differences were not exacerbated by the light exercise test. Heart rate responses showed both groups exercised at similar loads, though CFS patients perceived it as higher exertion.
This talk was given by Dr. Jennifer Huggins of Cincinnati Childrens Hospital, at the Systemic Juvenile Idiopathic Arthritis (or SJIA) Family Day, on July 22nd, 2017.
Among patients with heart failure with preserved ejection fraction (HFPEF), a randomized clinical trial found that 24 weeks of treatment with the phosphodiesterase-5 inhibitor sildenafil, compared to placebo, did not significantly improve exercise capacity as measured by peak oxygen consumption or clinical status. Median changes in peak oxygen consumption and 6-minute walk distance were not significantly different between the sildenafil and placebo groups. The mean clinical status rank score, a composite of time to death or hospitalization and quality of life, was also not significantly different between groups at 24 weeks. Adverse events occurred in similar proportions of patients in both groups.
Pearls about NSAIDs and their usage in the managaement of chronic pain, considering safety profile of both selective cox-2 or non selective cox-2 inhibitors
A prospective comparative study of three treatmentHemant Pippal
This study compared the effectiveness of three treatment modalities for idiopathic adhesive capsulitis of the shoulder: 1) conservative treatment including physical therapy, 2) intra-articular steroid injections plus physical therapy, and 3) arthroscopic capsular release plus physical therapy. The study found that arthroscopic capsular release resulted in significantly better improvement in external shoulder rotation compared to conservative treatment alone. However, overall functional outcomes as measured by a shoulder rating questionnaire were similar across groups. The study concluded that conservative treatment remains an effective first-line option for adhesive capsulitis, though arthroscopic release may provide faster recovery of external rotation.
- Gamma cyclodextrin is a torus-shaped molecule with a hydrophilic exterior and lipophilic interior that can encapsulate guest molecules. Sugammadex is a modified gamma cyclodextrin that can encapsulate the neuromuscular blocking drug rocuronium.
- By adding sugar side chains and ethyl carboxyl groups to gamma cyclodextrin, sugammadex was engineered to have a larger lipophilic cavity able to accommodate the rocuronium molecule and hold it electrostatically.
- Studies show sugammadex rapidly reverses moderate and deep neuromuscular blockade from rocuronium, with recovery times within minutes compared to hours with spontaneous recovery.
Prevention of Lower Extremity Stress FracturesJA Larson
This document summarizes a systematic review of the literature on preventing stress fractures in athletes and soldiers. It identifies 176 relevant studies, including 20 diagnostic case series, 66 clinical case series, 52 epidemiological studies, and 9 intervention trials. The review finds that bone scans are more sensitive but less specific than x-rays for diagnosing stress fractures. It also examines the reported incidence of stress fractures in military recruits and trainees. The goal of the review is to evaluate research on causes and risk factors of stress fractures, what is known about prevention, and make recommendations for future research.
Edelman-derived quantification of dyselectrolytemias.
Equation-based monitoring of hyponatremia therapy with a focus on safely and predictably increasing sodium as per guideline advice using a strategy involving desmopressin administration in severe hyponatremias, especially those patients at risk of becoming overcorrectors. Explanation of risk factors responsible for overshooting when correcting hyponatremia. Adrogue-Madias, Barsoum, Nguyen-Kurtz equations are explained and proven to be of help at least conceptually when attempting to have a desmopressin-guided therapy in hyponatremia. All recommendations are done in accordance with European and American guidelines published in 2013 and 2014.
Brief review including assessment of cryotherapy as
a tool of performance and a recovery method. Conclusions: Most studies
suggest that a short rewarming time would be beneficial (a couple minutes),
which is very reasonable in sports. Also, cooling techniques differ in its result
accordingly to the procedures and objectives used. Finally, the type of tissue
cooled plays a large role (ie. Joint vs. Muscle).
Evidence based radial shock wave therapyCORR MEDICAL
PEDRro: Physiotherapy Evidence Database. Radial Shockwave Therapy.
+info: http://ondaschoque.net
CORR MEDICAL. Expertos en ondas de choque ESWL, ESWT y rESW. Distribuidores exclusivos de los constructores líderes: Electro Medical Sytems y JenaMedTech.
Buying time in situations of extreme hemodynamic instability by partially reversing acidemia with a controlled strategy involving bicarbonate, calcium and hyperventilation.
Minimizing CO2 buildup as well as resulting hypocalcemia after alkalinization improves hemodynamics in a rat-derived french study.
A Practical Measure of Balance, Gait, and Muscular Power in Older Adults: The...Kyle Menkosky
This document describes the Short Physical Performance Battery (SPPB), which is a validated test used to assess physical function in older adults. The SPPB examines balance, gait, and lower body strength through tests of standing balance, walking speed, and repeated chair stands. It provides an overall score of 0-12 based on performance in each test. Studies have shown SPPB scores predict disability, nursing home admission, and mortality in older adults. The document argues the SPPB is a practical test that can be used in cardiac and pulmonary rehabilitation to safely identify frailty and guide exercise interventions to improve outcomes in older patients.
Monitoring solutions entropy publications reference list august 2016grattoanestesista
This document is a reference list containing over 80 peer-reviewed articles and abstracts related to the use of entropy monitoring during anesthesia and sedation. The articles are grouped into sections on peer-reviewed articles, articles categorized by topic, and abstracts. The reference list was published by Entropy Publications in June 2016 and includes works published between 2004-2016 that discuss the use of entropy monitoring to measure the effects of various anesthetic agents on the brain.
19 rbeb relationship between peak and mean amplitudes v29n2Nathanael Amparo
The document describes a study that investigated the relationship between peak and mean amplitudes of stimulator output voltage during functional electrical stimulation (FES) of the knee. Ten healthy volunteers and ten spinal cord injured volunteers participated. Four different FES profiles were tested to determine which produced the lowest peak and mean amplitudes needed to extend the knee from 90 to 40 degrees. The results showed that higher amplitudes were required for spinal cord injured volunteers compared to healthy volunteers. The profile with 100 microsecond pulses at 50 Hz produced the lowest mean amplitudes for both groups.
NSAID and Their Effect on Bone Remodeling and RepairAndrew Beardsall
This document summarizes research on the effects of non-steroidal anti-inflammatory drugs (NSAIDs) on bone remodeling and repair. It finds that NSAIDs in the non-selective category (nsNSAIDs) like ibuprofen and diclofenac negatively impact bone health based on animal and human studies. Animal studies show nsNSAIDs decrease biomechanical strength and bone mineral density during fracture healing. Human studies find nsNSAIDs reduce prostaglandin levels and bone mineral gains from exercise. More research is still needed on chronic use, optimal dosage timing, and relationships to re-fracture risk. The document also introduces research on selective NSAIDs but does not summarize findings.
El documento discute las marcas de vehículos más buscadas en Google como Volvo, BMW y Audi. También analiza las regiones donde estas marcas tienen mayor participación en el mercado, las expectativas de los consumidores de lujo, y el perfil general del consumidor de automóviles.
Liver ischemia/reperfusion injury, a setting in which the functional mass is ...Prof. Hesham N. Mustafa
The document discusses a study on the effects of the phosphodiesterase type-5 (PDE5) inhibitor tadalafil on liver ischemia/reperfusion injury in rats. The study found that tadalafil treatment before ischemia/reperfusion injury helped restore normal liver enzyme levels, reduced oxidative stress and inflammation in liver tissue, and decreased levels of tumor necrosis factor-alpha, interleukin-6, and intercellular adhesion molecule-1. Histological analysis also showed tadalafil treatment helped protect against liver damage. The findings suggest that modulating the inflammatory response may be one mechanism by which tadalafil provides hepatoprotection against ischemia/reperfusion injury.
39689944 Age Loc Vitality Ingredient Vtudies[1]Laura Fallon
This study examined the effects of Cordyceps sinensis Cs-4 supplementation on age-related changes in the expression of mitochondrial genes in mouse skeletal muscle and brain tissue. The researchers identified 393 genes related to mitochondria that changed expression with age in these tissues. Cs-4 supplementation opposed age-related changes in 52 of these genes, with 92% changing in a direction associated with younger gene expression. Analysis also showed Cs-4 impacted several gene pathways associated with aging in muscle tissue. The results provide evidence that Cs-4 can modulate aging effects at the transcriptional level in muscles and brain.
Am j physiol heart circ physiol 2000-matsubara-h1534-9Natasha Xavier
This document reports on a study investigating the influence of myocardial collagen content on rat papillary muscle function. Three groups of rats were studied: 1) a renal hypertension group with increased collagen (RHTR), 2) a group with decreased collagen through glutathione infusion (GSSG), and 3) untreated controls. The main findings were:
1) GSSG rats had increased active stiffness and myocyte size compared to controls, suggesting decreased collagen is related to hypertrophy and increased active stiffness.
2) Passive tension-length curves were shifted down in GSSG rats, indicating decreased passive stiffness, and up in RHTR rats, indicating increased passive stiffness.
3) Changes in collagen content bidirectionally influence
Viscosupplementation, PRP Steroids-Consensus in OA-Dr. M.S.DhillonTheRightDoctors
The document discusses different injection treatments for osteoarthritis (OA), including corticosteroids, hyaluronic acid injections, and platelet-rich plasma (PRP). It provides an overview of the mechanisms of action and evidence for each treatment. For PRP specifically, it summarizes that PRP is safe for treating OA and can provide symptomatic relief for up to 3 months, though more research is still needed to determine optimal formulations and treatment protocols.
This study investigated gait and balance in patients with Chronic Fatigue Syndrome (CFS) compared to healthy sedentary controls. 11 CFS patients and 11 matched controls performed balance and gait tests before and after a 15-minute sub-anaerobic exercise test on a bicycle ergometer. Results showed no significant differences in postural sway between groups before or after exercise. However, several gait parameters were significantly different between CFS patients and controls, confirming reports of gait abnormalities in CFS patients. These gait differences were not exacerbated by the light exercise test. Heart rate responses showed both groups exercised at similar loads, though CFS patients perceived it as higher exertion.
This talk was given by Dr. Jennifer Huggins of Cincinnati Childrens Hospital, at the Systemic Juvenile Idiopathic Arthritis (or SJIA) Family Day, on July 22nd, 2017.
Among patients with heart failure with preserved ejection fraction (HFPEF), a randomized clinical trial found that 24 weeks of treatment with the phosphodiesterase-5 inhibitor sildenafil, compared to placebo, did not significantly improve exercise capacity as measured by peak oxygen consumption or clinical status. Median changes in peak oxygen consumption and 6-minute walk distance were not significantly different between the sildenafil and placebo groups. The mean clinical status rank score, a composite of time to death or hospitalization and quality of life, was also not significantly different between groups at 24 weeks. Adverse events occurred in similar proportions of patients in both groups.
Pearls about NSAIDs and their usage in the managaement of chronic pain, considering safety profile of both selective cox-2 or non selective cox-2 inhibitors
A prospective comparative study of three treatmentHemant Pippal
This study compared the effectiveness of three treatment modalities for idiopathic adhesive capsulitis of the shoulder: 1) conservative treatment including physical therapy, 2) intra-articular steroid injections plus physical therapy, and 3) arthroscopic capsular release plus physical therapy. The study found that arthroscopic capsular release resulted in significantly better improvement in external shoulder rotation compared to conservative treatment alone. However, overall functional outcomes as measured by a shoulder rating questionnaire were similar across groups. The study concluded that conservative treatment remains an effective first-line option for adhesive capsulitis, though arthroscopic release may provide faster recovery of external rotation.
- Gamma cyclodextrin is a torus-shaped molecule with a hydrophilic exterior and lipophilic interior that can encapsulate guest molecules. Sugammadex is a modified gamma cyclodextrin that can encapsulate the neuromuscular blocking drug rocuronium.
- By adding sugar side chains and ethyl carboxyl groups to gamma cyclodextrin, sugammadex was engineered to have a larger lipophilic cavity able to accommodate the rocuronium molecule and hold it electrostatically.
- Studies show sugammadex rapidly reverses moderate and deep neuromuscular blockade from rocuronium, with recovery times within minutes compared to hours with spontaneous recovery.
Prevention of Lower Extremity Stress FracturesJA Larson
This document summarizes a systematic review of the literature on preventing stress fractures in athletes and soldiers. It identifies 176 relevant studies, including 20 diagnostic case series, 66 clinical case series, 52 epidemiological studies, and 9 intervention trials. The review finds that bone scans are more sensitive but less specific than x-rays for diagnosing stress fractures. It also examines the reported incidence of stress fractures in military recruits and trainees. The goal of the review is to evaluate research on causes and risk factors of stress fractures, what is known about prevention, and make recommendations for future research.
Edelman-derived quantification of dyselectrolytemias.
Equation-based monitoring of hyponatremia therapy with a focus on safely and predictably increasing sodium as per guideline advice using a strategy involving desmopressin administration in severe hyponatremias, especially those patients at risk of becoming overcorrectors. Explanation of risk factors responsible for overshooting when correcting hyponatremia. Adrogue-Madias, Barsoum, Nguyen-Kurtz equations are explained and proven to be of help at least conceptually when attempting to have a desmopressin-guided therapy in hyponatremia. All recommendations are done in accordance with European and American guidelines published in 2013 and 2014.
Brief review including assessment of cryotherapy as
a tool of performance and a recovery method. Conclusions: Most studies
suggest that a short rewarming time would be beneficial (a couple minutes),
which is very reasonable in sports. Also, cooling techniques differ in its result
accordingly to the procedures and objectives used. Finally, the type of tissue
cooled plays a large role (ie. Joint vs. Muscle).
Evidence based radial shock wave therapyCORR MEDICAL
PEDRro: Physiotherapy Evidence Database. Radial Shockwave Therapy.
+info: http://ondaschoque.net
CORR MEDICAL. Expertos en ondas de choque ESWL, ESWT y rESW. Distribuidores exclusivos de los constructores líderes: Electro Medical Sytems y JenaMedTech.
Buying time in situations of extreme hemodynamic instability by partially reversing acidemia with a controlled strategy involving bicarbonate, calcium and hyperventilation.
Minimizing CO2 buildup as well as resulting hypocalcemia after alkalinization improves hemodynamics in a rat-derived french study.
A Practical Measure of Balance, Gait, and Muscular Power in Older Adults: The...Kyle Menkosky
This document describes the Short Physical Performance Battery (SPPB), which is a validated test used to assess physical function in older adults. The SPPB examines balance, gait, and lower body strength through tests of standing balance, walking speed, and repeated chair stands. It provides an overall score of 0-12 based on performance in each test. Studies have shown SPPB scores predict disability, nursing home admission, and mortality in older adults. The document argues the SPPB is a practical test that can be used in cardiac and pulmonary rehabilitation to safely identify frailty and guide exercise interventions to improve outcomes in older patients.
Monitoring solutions entropy publications reference list august 2016grattoanestesista
This document is a reference list containing over 80 peer-reviewed articles and abstracts related to the use of entropy monitoring during anesthesia and sedation. The articles are grouped into sections on peer-reviewed articles, articles categorized by topic, and abstracts. The reference list was published by Entropy Publications in June 2016 and includes works published between 2004-2016 that discuss the use of entropy monitoring to measure the effects of various anesthetic agents on the brain.
19 rbeb relationship between peak and mean amplitudes v29n2Nathanael Amparo
The document describes a study that investigated the relationship between peak and mean amplitudes of stimulator output voltage during functional electrical stimulation (FES) of the knee. Ten healthy volunteers and ten spinal cord injured volunteers participated. Four different FES profiles were tested to determine which produced the lowest peak and mean amplitudes needed to extend the knee from 90 to 40 degrees. The results showed that higher amplitudes were required for spinal cord injured volunteers compared to healthy volunteers. The profile with 100 microsecond pulses at 50 Hz produced the lowest mean amplitudes for both groups.
NSAID and Their Effect on Bone Remodeling and RepairAndrew Beardsall
This document summarizes research on the effects of non-steroidal anti-inflammatory drugs (NSAIDs) on bone remodeling and repair. It finds that NSAIDs in the non-selective category (nsNSAIDs) like ibuprofen and diclofenac negatively impact bone health based on animal and human studies. Animal studies show nsNSAIDs decrease biomechanical strength and bone mineral density during fracture healing. Human studies find nsNSAIDs reduce prostaglandin levels and bone mineral gains from exercise. More research is still needed on chronic use, optimal dosage timing, and relationships to re-fracture risk. The document also introduces research on selective NSAIDs but does not summarize findings.
El documento discute las marcas de vehículos más buscadas en Google como Volvo, BMW y Audi. También analiza las regiones donde estas marcas tienen mayor participación en el mercado, las expectativas de los consumidores de lujo, y el perfil general del consumidor de automóviles.
We used our thinking skills and the HATS method to reflect on and evaluate a triathlon event, considering what went well and what could be improved. This helped us generate ideas for planning an even better triathlon next year by looking at the event through different perspectives represented by the colors of the thinking hats. The most important takeaway was applying all of our thoughts to enhancing the triathlon experience for future participants.
MIXED MIGRATION FLOWS IN EUROPE VIA THE WESTERN BALKANS ROUTEМЦМС | MCIC
The document summarizes mixed migration flows through the Western Balkans route to Europe from June to October 2015. It finds that over 250,000 people traveled this route, most were male (59%), with minors making up 21% and unaccompanied minors 5%. The top nationalities were Syrian (62%), Afghan (22%), and Iraqi (8%). Characteristics included a continuous rise in numbers, more unaccompanied minors, and a decreased proportion of Syrians and increased proportion of Afghans. Germany received the most first time asylum applications (38%), followed by Hungary (15%) and Austria (8%). Recognition rates for protection statuses were high for Syrians (96%), Eritreans (
VACANCY: Snr Program Assistant G5 AlinjugurUNHCR KENYA
The United Nations High Commissioner for Refugees (UNHCR) is seeking a Senior Programme Assistant in Alinjugur, Kenya. The position provides administrative support to the country office's Programme Section to better meet the needs of refugees. Key responsibilities include collecting and reporting programme information, preparing documents, monitoring implementing partner agreements, and representing UNHCR in project monitoring visits. Applicants should have a secondary education in a relevant field, 4 years of relevant experience, computer skills, and English fluency. The position requires strong competencies in accountability, teamwork, communication, and client and results orientation.
This certificate was awarded to Timur Niyazov for successfully completing the course "AGD - Implementing the AGD Approach" provided by UNHCR Online Courses, as of August 24, 2016.
The document discusses SEO strategies at The Next Web, a technology media company. Some key points:
- They focus heavily on content creation, with 15 editors publishing around 30 new articles daily. Content is optimized for search and engagement.
- They take an in-house and data-driven approach, building their own SEO tools to track rankings and volumes at scale.
- Other efforts include using structured data, third-party partnerships like Google AMP, and continuous monitoring to improve speed and performance.
- The goal is for massive traffic and scale through innovative technical solutions and a focus on engagement and knowledge building through high-quality content.
Gestor de proyecto educativo tic terminado.jorge quiñones
Este documento presenta un proyecto educativo TIC para mejorar el desempeño de estudiantes de primaria en las pruebas Saber. El proyecto incluye sesiones de entrenamiento con herramientas tecnológicas y lúdicas. Se desarrollará en un colegio de Barranquilla durante 8 horas académicas utilizando recursos digitales como contenidos interactivos y cuadernillos Saber. El proyecto concluirá con una socialización de los resultados obtenidos.
Поддержка местной экономики муниципалитетамиKomitetGI
О правовых основах и практическом опыте поддержки местной экономики муниципалитетами в Германии рассказала г-жа Гудрун Гризер - в прошлом более 17 лет работавшая обер-бургомистром города Швайнфурт. По ее словам, финансовые ресурсы территориальных бюджетов регулируются на местном, а не на федеральном уровне. Их основу составляют налоговые поступления. Государственные дотации существуют для «выравнивания ситуации, чтоб не было экстремальных искажений». Чем шире у муниципалитета собственные возможности для пополнения бюджета, чем больше налоговые поступления, тем меньше объем субсидий, пояснила г-жа Гудрун Гризер
ThinkNation: "Women quotas in tech" Naomi Trickey, BrandwatchLizzie Hodgson
This document discusses quotas for increasing gender diversity in tech. It provides statistics showing low percentages of women employed in major tech companies, ranging from 10-20% typically. It then shares the gender breakdown of employees at Brandwatch, showing 51% male and 49% female overall. The document questions whether quotas are a blunt instrument approach, and suggests more nuanced alternatives may be better, such as focusing on recruitment, culture changes, training, mentoring and career planning to increase diversity.
MongoDB World 2016: Lunch & Learn: Google Cloud for the EnterpriseMongoDB
The document summarizes the evolution of cloud computing and Google Cloud Platform's offerings. It discusses how cloud infrastructure has moved from colocated data centers (1st wave) to virtualized infrastructure (2nd wave) to automated services and scalable data (3rd wave). It then provides an overview of Google Cloud Platform's compute, storage, database, analytics and machine learning services and how they make complex data analysis simpler. The document positions Google Cloud Platform as building on Google's expertise in infrastructure and data to provide customers an advantage.
A Sudanese lawyer seeking a new challenging position provides a summary of his qualifications and experience. He has over 15 years of experience as a lawyer, including advising clients on contracts, intellectual property, and international law. He has advanced degrees in law and has completed training in fields like arbitration, copyright, and computer software. He aims to resolve legal issues efficiently and improve processes.
Natriuretic peptides and oxygen: a narrative reviewOlliArjamaa
- In the 1950s, electron microscopy revealed small granules in mammalian heart atria, though images were low quality.
- In 1964, Palade and Jamieson published an extensive paper showing the granules resembled those in pancreatic cells and were only present in atria, not ventricles. They concluded the atria had a secretory function.
- If one person led the discovery of natriuretic peptides, it was Adolfo de Bold in the 1970s, whose work showed atrial extracts caused natriuresis and diuresis in animals. This triggered worldwide research on atrial natriuretic factor.
- The document discusses the endothelium and how it becomes dysfunctional during chronic kidney disease (CKD).
- The endothelium normally regulates vasodilation, coagulation, inflammation, and regeneration, but during CKD it exhibits defects in these functions due to the accumulation of uremic toxins.
- Uremic toxins like indoxyl sulfate and p-cresol sulfate increase oxidative stress and damage endothelial cells, impairing nitric oxide production and promoting a proinflammatory phenotype.
- Reducing the levels of these toxins through dietary changes or toxin-binding therapies may help restore healthy endothelial function and reduce cardiovascular risk in CKD patients.
Temporal-Spatial Expressions of Spy1 in Rat Sciatic Nerve After CrushJiao Yang
1. The study examined the expression of the cell cycle protein Spy1 in a rat sciatic nerve crush injury model over time.
2. Spy1 expression was found to gradually increase after injury, peaking at day 3, due to increased expression in both axons and Schwann cells.
3. Spy1 expression correlated with Schwann cell proliferation after injury and Spy1 was found to localize in axons in the injured segment but did not co-localize with the growth protein GAP43.
The document summarizes key findings from the North American Stroke Meeting in 2003 regarding stem cell transplantation for stroke. It discusses how immortalized stem cell lines can be mass produced and derived without ethical concerns. A phase 1 trial injected cryopreserved stem cells into 12 patients with basal ganglia strokes, finding subjective improvement in functions and increased metabolism at the injury site. A phase 2 trial of 14 patients receiving different stem cell doses found some improvement on stroke scales but left questions unanswered. Future research is needed to optimize timing, locations and doses of stem cell transplantation for stroke patients.
This study examined how type 2 diabetic Goto-Kakizaki (GK) rats respond differently than healthy Wistar rats to activation of the autonomic nervous system by intracisternal injection of thyrotropin-releasing hormone (TRH). The GK rats had higher baseline blood glucose levels compared to Wistar rats. TRH injection induced a greater insulin response but smaller decrease in blood glucose in GK rats, indicating impaired insulin secretion and action. Vagotomy blocked the insulin response, while adrenalectomy prevented the rise in blood glucose, showing the involvement of the vagus nerve and adrenal glands. The GK rats also had higher basal insulin gene expression but a lower response to TRH
EFFECT OF 6-HYDROXYDOPAMINE AND OVARIECTOMY IN HEART RATE VARIABILITY OF FEMA...Tomás de la Rosa
ePoster entitled "EFFECT OF 6-HYDROXYDOPAMINE AND OVARIECTOMY IN HEART RATE VARIABILITY OF FEMALE RODENTS
" presented at "AD/PD 15th International Congress"
This research article examines the potential disease-modifying effect of adiponectin (APN) in models of alpha-synucleinopathies such as Parkinson's disease and dementia with Lewy bodies. The study finds that APN is localized within Lewy bodies in human brain tissue from patients with these conditions. In cell and mouse models expressing alpha-synuclein, APN treatment suppressed alpha-synuclein aggregation, phosphorylation, and release through an AdipoR1-AMPK pathway. Intranasal APN treatment in transgenic mice improved histopathology and motor function when initiated early. APN may exert these effects by modifying metabolic pathways to have a therapeutic potential for alpha-synu
This research article examines the potential disease-modifying effect of adiponectin (APN) in models of alpha-synucleinopathies such as Parkinson's disease and dementia with Lewy bodies. The study finds that APN is localized in Lewy bodies in autopsy brain samples of patients with these conditions. In neuronal cell models expressing alpha-synuclein, APN treatment reduces aggregation and phosphorylation of alpha-synuclein through an AdipoR1-AMP kinase pathway. Intranasal APN treatment in transgenic mouse models also improves histopathology and movement disorders when initiated early. The study suggests APN may suppress neurodegeneration through metabolic pathway modification and have therapeutic potential for alpha-
THE FIRST SYSTEM OF REFERENCE FOR THE MEDICAL PRACTICE OF HOMEOPATHY IN FRANCEhome
PB7 445 THE FIRST SYSTEM OF REFERENCE FOR THE MEDICAL PRACTICE
OF HOMEOPATHY IN FRANCE
J. BILLOT* (AP-HP Hôpital Corenton-Celton, Issy-les -Moulineaux, France)
Introduction At least 30% of the French population has recourse to homeopathy, with a large
proportion of elderly persons. Some 25000 practitioners prescribe homeopathic treatments.
Object: Development of a system of reference for the medical practice of homeopathy in
order to meet with the legal obligations of evaluation and training of homeopaths. Method :
1- Creation by the Société Française d’Homéopathie of a working group of expert specialists
representative of the medical practice of homeopathy to determine: - a basic methodology:
self-evaluation according to the method of practice groups; - the subject: « the homeopathic
medical file»; - the aims and requirements of quality; - the standards of evaluation; - the
number and content of items or inquiries 2- Verification of the text’s form by a reader’s
group; 3- Verification of acceptability and feasibility by a group test; 4- New meeting of the
working group to register the modifications shown necessary by the feasibility study; 5-
Presentation of the text to the methodologists approved by the Haute Autorité de la Santé
(Health Department); 6- Finalization of the project and transmission to the Haute Autorité de
la Santé for validation. Results: Elaboration of a system of analysis with reference to the
«homeopathic medical file», according to the method of practice groups. This system of
reference includes a questionnaire concerning the symptoms noted in the patient’s file: in
order to be of homeopathic value, the symptoms must be precisely characterized and
organized according to their relative importance. Conclusion This system of reference was
validated by the Haute Autorité de la Santé in February 2007. Several practice groups have
already used this system of reference to validate the legal obligations of their profesional
practice. The complete text of this system of reference can be downloaded on web-site:
WWW. homeopathie- francaise. fr
This study investigated the effects of L-alpha-glycerylphosphorylcholine (GPC), a deacylated derivative of phosphatidylcholine (PC), in a rat model of small intestinal ischemia-reperfusion injury. The results showed that:
1) Intestinal ischemia-reperfusion increased oxidative stress markers, microcirculatory dysfunction, and liver ATP depletion.
2) Both pre-treatment and post-treatment with GPC significantly reduced oxidative stress markers, protected microcirculation, and alleviated hepatic ATP depletion caused by ischemia-reperfusion.
3) GPC therapies were effective in attenuating the inflammatory response to ischemia-reperfusion injury, providing indirect
Rosalina Villalon Landeros is a PhD candidate at the University of Wisconsin-Madison studying under Professor R Magness. Her research examines the role of estradiol-17β and its metabolites in vascular endothelial function using an ovine model of unilateral pregnancy. She hypothesizes that uterine artery endothelial cells isolated from the gravid horn will exhibit pregnancy-specific responses to estradiol, while cells from the non-gravid horn will not. Preliminary results support increased proliferation and nitric oxide production in response to estradiol metabolites in cells from the gravid horn.
The document summarizes a research study that tested the effects of combining a von Willebrand factor neutralizing antibody (AJW200) with low-dose tissue plasminogen activator (tPA) treatment after embolic stroke in rabbits. The study found that the combination of AJW200 and low-dose tPA significantly improved behavioral outcomes compared to low-dose tPA or IgG control, and produced similar effects to standard-dose tPA alone. This suggests that neutralizing von Willebrand factor may help suppress acute stroke responses like inflammation and platelet aggregation, and could allow the use of lower, safer tPA doses for stroke treatment.
This study investigated the use of noninvasive neuromodulation strategies to reactivate motor control in individuals with complete paralysis. Specifically, it used transcutaneous electrical stimulation of the spinal cord combined with passive limb movements and pharmacological intervention to facilitate voluntary locomotor-like movements. Over 18 weeks of weekly training, all 5 subjects showed improvements in their ability to generate stepping movements, both with and without stimulation. Electrophysiological data provided evidence that connectivity between the brain and spinal cord was reestablished. The combined noninvasive strategies were able to transform dormant neural networks into functional systems capable of voluntary movement recovery after complete paralysis.
Cell-Replacement Therapy with Stem Cells in Neurodegenerative DiseasesSararajputsa
This document summarizes research on using stem cell transplantation as a potential therapy for neurodegenerative diseases like Amyotrophic Lateral Sclerosis (ALS). It discusses how stem cell transplantation has shown effectiveness in animal models of ALS through mechanisms like cell replacement, neurotrophic factor release, and endogenous stem cell proliferation. Early clinical trials transplanting stem cells into ALS patients showed feasibility and no severe side effects. However, more research is still needed to fully understand stem cell mechanisms and maximize their therapeutic potential for neurodegenerative diseases.
The study examined the effects of combining alendronate (ALN), a bisphosphonate, with human parathyroid hormone (PTH) administered daily or cyclically on bone strength in mice. Mice were treated with ALN alone, PTH alone daily or cyclically, or combinations of ALN and PTH daily or cyclically. Bone mineral density, structure, strength, and markers were measured after 7 weeks. The results showed that combinations of ALN and PTH, both daily and cyclically, produced greater increases in bone mineral density and strength than either treatment alone, indicating complementary mechanisms of action. PTH and ALN had synergistic effects on bone strength in the lumbar vertebrae and additive
Impact of Social Isolation on Serum Sodium and Cortisol Level in male Wistar ...ijtsrd
Background Aim Loneliness due to social isolation is a source of psychological stress in adults. This study evaluated the impact of social Isolation on serum sodium and cortisol level in male wistar ratsMethods Sixteen male wistar rats were randomly divided into two groups n = 8 , Group 1 served as control. And were socially housed. Group 2 consisted of eight individually caged Wistar rats. The animals had access to food and water ad libitum and their level of physical activity was observed. After six weeks of Isolation, blood was collected from the animals via ocular puncture for Serum Cortisol and Sodium ion analysis, all data was analysed using SPSS software version 25.0. Values were considered significant at P 0.05.Results Results showed significant increase in the mean cortisol 33.82 ± 1.17 , decrease in mean sodium ion 113.875 ± 5.24 and negative correlation between sodium and cortisol.Conclusion The results from this study have shown that social isolation is a source of psychological stress which leads to depression and hyponatraemia. Uzoma Reichmann Iheanyi | Ufearo Chibueze Steven | Njoku-Oji Nancy Njideka | Okonkwo Chukwudi Onyeka | Muorah Chinecherem Onyekachi | Umeasiegbu Adaobi Chidinma "Impact of Social Isolation on Serum Sodium and Cortisol Level in male Wistar Rats" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-5 | Issue-5 , August 2021, URL: https://www.ijtsrd.com/papers/ijtsrd46294.pdf Paper URL: https://www.ijtsrd.com/medicine/physiology/46294/impact-of-social-isolation-on-serum-sodium-and-cortisol-level-in-male-wistar-rats/uzoma-reichmann-iheanyi
Effect of carvedilol on atrial remodeling in canine model of atrial fibrillation
Authors: Jun Kishihara, Shinichi Niwano, Hiroe Niwano, Yuya Aoyama, Akira Satoh, Jun Oikawa, Michiro Kiryu, Hidehira Fukaya, Yoshihiko Masaki, Hideaki Tamaki, Tohru Izumi, Junya Ako
There were significant decreases in the cytokines interleukin-6 and interleukin-11 in rats administered the combined oral contraceptive DUOFEM, but no significant change in erythropoietin levels. While further study is needed, current evidence suggests that DUOFEM use provides contraceptive benefits with minimal potential adverse effects in healthy users. The decreases in interleukin levels are consistent with previous research showing estrogen can decrease interleukin expression and production.
STEREOLOGICAL EVIDENCES OF EPITHELIAL HYPOPLASIA OF SEMINIFEROUS TUBULES INDU...lukeman Joseph Ade shittu
BACKGROUND: Anabolic-androgenic steroid compounds are one of the most widely abused drugs by athletes and muscle builders with the goal of improving performance/ability, appearance, or muscle mass. In addition, these steroids are widely used in the treatment of male infertility and subfertility. However, increasing concern has been shown that these compounds may not only offer unappreciable benefits to infertile and subfertile males, but might have deleterious effects on both human and animal physiology and sperm quality. There is a dearth of knowledge on the structural and quantitative changes of the testis secondary to this group of compounds. Objective: The present study was carried out to evaluate the effects of mesterolone (proviron), an anabolic-androgenic steroid, on some of the histomorphometric and stereological parameters of the seminiferous tubules in Sprague-Dawley rat. Materials and Methods: Two groups of 10 adult male rats were used. The treated group was given 0.06 mg/kg body weight/day of mesterolone by gavage for six weeks while the control group received equal volume of 0.9% normal saline per day. Five µm of uniformly random serial sections of the processed testicular tissues were analyzed using un-biased stereological and histomorphometric studies. Results: The results showed that the percentage mean volume density of both the tubular lumen and epithelial height increased by 35% (p< 0.05) and decreased by 50% (p<0.05), respectively compared to the control. mesterolone also caused a significant decline in sperm concentration. Conclusion: Mesterolone produces epithelial hypoplasia in the testis post continuous management.
1) This study found that in a rat model of pulmonary hypertension (PH), female rats developed more pronounced thickening of small pulmonary arteries compared to male rats. However, only male rats showed infiltration of inflammatory cells in the small pulmonary arteries and associated fibrosis.
2) While peak right ventricular systolic pressure was similar between males and females, male rats had worse survival and more severe right ventricular fibrosis and dysfunction.
3) The results suggest that in PH, females experience greater pulmonary artery remodeling but better survival, while pulmonary and cardiac fibrosis in males leads to more severe right ventricular failure and lower survival rates.
Similar to Am J Physiol Regul Integr Comp Physiol-2012-Evanson-R651-7 (20)
4. 17-estradiol pellet (60-day release, 4 g/day; Innovative Research of
America, Sarasota, FL) immediately after ovariectomy. 17-Estradiol
pellets were inserted subcutaneously at the dorsoscapular region just
behind the left ear above the shoulder using a 10-gauge trochar.
Animal behavior, food and water intake, appearance, and surgical
incisions were monitored for 10 days postoperatively. Animals were
housed for 8 wk following the procedure to allow for vascular
adaptations associated with long-term estradiol treatment to occur
(21). Rats were housed at the university’s animal care facility under
static environmental conditions (22°C; 12:12 h light/dark cycle).
Water and rat chow were provided ad libitum. Animal care and
experimental protocols were approved by the University of Arkansas
Institutional Animal Care and Use Committee.
Body weight (12, 37), uterine weight (21, 35), and bone morphol-
ogy (4, 36, 43, 46) are responsive to estradiol and can be used as
measures to ascertain estradiol status. Body weight was recorded
before the euthanizing procedure. Rats were euthanized with an
overdose of pentobarbital (40 mg/kg ip) followed by pneumothorax
with the depth of anesthesia determined through flexor withdrawal
reflex in response to a foot pinch. The uterus was removed and
surrounding connective tissue trimmed away to assess uterine weight.
Evaluation of bone microarchitectural properties via bone
histomorphometry. Right femurs from OVX (n ϭ 5) and OVE (n ϭ
5) rats were dissected,fixed in 10% formalin for 3 days, dehydrated,
and embedded in methylmethacrylate at low temperature. The distal
femoral metaphysis was sectioned frontally with a microtome (Leica
RM2255, Leica Microsystems, Bannockburn), and histological slides
were created. Two 9-m-thick histological sections stained with
Goldner’s trichrome were used for measurement of bone micro-
architectural properties [i.e., bone volume to total volume ratio
(BV/TV, %), trabecular thickness (Tb.Th, m), trabecular number
(Tb.N /mm2
), and trabecular separation (Tb.Sp, m)] using the
OsteoMeasure bone histomorphometry analysis system (OsteoMet-
rics, Decatur, GA).
Vessel preparation. Red gastrocnemius first-order arterioles were
removed and placed in a cold (4°C) Krebs-Ringer physiological saline
solution (in mmol/l: 119 NaCl, 4.7 KCl, 2.5 CaCl2, 1.2 MgSO4, 25
NaHCO3, 1.2 KH2PO4, 5.5 glucose, and 2 glycerol). Arterioles
designated for DPPIV activity analysis were homogenized in 200 l
of warm (37°C) Krebs-Ringer physiological saline solution, centri-
fuged for 3 min (2,000 g), and the supernatant removed. All samples
were flash frozen and stored at Ϫ80°C.
NPY sampling and analysis. Arterioles for NPY analysis were
transferred to a vessel chamber (Living Systems, Burlington, VT)
with the ends secured to micropipettes using 11–0 ophthalmic suture.
The vessel bath contained a Krebs-Ringer physiological saline solu-
tion (37°C, pH 7.4, bubbled with 5% CO2-30% O2), and the vessel
was perfused with Krebs-Ringer physiological saline solution con-
taining 1% albumin (37°C, pH 7.4) (34). The vessel chamber was
transferred to the stage of an inverted microscope (Olympus CKX41,
Melville, NY). A sampling port was placed within the vessel chamber
juxtaposed to the suspended vessel. The micropipettes were connected
to independent reservoir systems. Initial luminal pressure was set at 60
cmH2O for 30 min. Luminal pressure was then increased to 90
cmH2O, which is a pressure associated with normal in vivo conditions
(49). The bath solution was replaced at 15-min intervals during
equilibration. The arterioles were considered viable if they were able
to constrict by 10% in response to phenylephrine (10 mol/l) and to
dilate by 20% to acetylcholine (1 mol/l) (39).
Field stimulation was delivered via two parallel platinum elec-
trodes placed on either side of the vessel. The electrical current was
supplied using a DS3 isolated constant current stimulator (Digitimer,
Letchworth Garden City, UK) interfaced with a Powerlab 16/30 with
Chart software (version 5.2; ADI Instruments, Colorado Springs, CO).
The exocytosis of large dense-cored vesicles that store NPY occurs at
higher neural frequencies (7, 20, 24–25); therefore, 60 Hz, 32 mA,
and 200 impulses were selected to elicit NPY release (8). Bath
samples (200 l) were taken before field stimulation (baseline),
immediately following the cessation of field stimulation (0 s), and 30 s
postfield stimulation. For experiments assessing the effects of DPPIV
activity on NPY overflow, a DPPIV inhibitor, diprotin A (4 mol/l;
Sigma-Aldrich, St. Louis, MO), was added to the vessel bath and
allowed to incubate for 20 min. Field stimulation and sampling time
points were performed as previously stated. Samples were flash frozen
and stored at Ϫ80°C. A peptide enzyme immunoassay (S-1145;
Bachem, King of Prussia, PA) was used to determine NPY overflow
as previously described (8). The assay had a minimum detectable
concentration of 0.04–0.06 ng/ml.
DPPIV activity analysis. DPPIV samples were brought to room
temperature along with assay components. Incubation buffer (50
mmol/l Tris·HCl, pH 8.3), substrate solution (20 mmol/l glycyl-L-
proline-4-methoxy-2-naphthylamide), and DPPIV sample were added
to the sample wells of a black 96-well microplate, while standard
solution (50 mmol/l 4-methoxy-2-naphthylamine), “stopping” solu-
tion (100 mmol/l citrate, pH 4.0), substrate solution, and incubation
buffer were added to the standard wells. The microplate incubated on
a heating block (37°C) for 30 min, and the reaction was terminated
with stopping solution. Fluorescence was excited at 360 and measured
at 440 nm on a FLX800 fluorometer (Biotek Instruments, Winooski,
VT). The minimum detection limit for enzyme activity of this assay is
5 mol·lϪ1
·minϪ1
(38).
Vasomotor response. Cumulative concentration response curves
were performed to elucidate arteriole response to an NPY analogue.
Vessel (luminal) diameter was measured through the use of video
calipers (307A Horizontal Video Calipers, Colorado Video, Boulder,
CO). NPY-mediated vasoconstriction was assessed using the
postjunctional Y1-receptor agonist [Leu31Pro34]NPY (1 pmol/l-10
mol/l; Bachem). This Y1-receptor agonist was equipotent to NPY in
stimulating Y1-receptor-mediated actions such as vasoconstriction
(19) or potentiation of adrenergic vasoconstriction (50). An ␣-adre-
noceptor agonist norepinephrine (NE, 100 fmol/l-100 mol/l; Sigma-
Aldrich) was used to establish a baseline EC50 and slope to examine
the efficacy of [Leu31Pro34]NPY to potentiate adrenergic vasocon-
striction. Y1-receptor-mediated potentiation of adrenergic vasocon-
striction was determined by adding a single concentration of
[LeuPro34]NPY (98 nmol/l) 5 min before performing the second
adrenergic cumulative concentration response curve. This concentra-
tion of Y1-receptor agonist was within a range of concentrations
capable of eliciting potentiation of NE-mediated vasoconstriction (13,
28). The vessel bath was rinsed five times following each cumulative
concentration response curve. Data were presented as a percentage of
the maximum vasoconstriction achieved with KCl (80 mmol/l) and
NE (10 mol/l). The concentration response curves were fit using
GraphPad Prism 5 for windows (San Diego, CA) using the equation
below.
Y ϭ Minimum ϩ ͑Maximum Ϫ Minimum͒ ⁄
͕1 ϩ 10͓͑LogEC50ϪX͒ ● Hill Slope͔
͖
where Y is the percentage of maximum vasoconstriction, X is the drug
concentration, “minimum” and “maximum” represent the respective
range of percentage of maximum vasoconstriction, EC50 is the drug
concentration that elicits 50% of maximum vasoconstriction, and the
Hill slope represents the steepness of the curve.
Statistical analysis. Data were expressed as means Ϯ SE. NPY
overflow mean data were derived using difference scores from base-
line (⌬) NPY levels (expressed in ng/ml). NPY overflow data during
control and DPPIV inhibition conditions were analyzed using a
repeated measures one-way analysis of variance (SAS 9.1.3, Cary,
NC). Differences in animal descriptive characteristics, bone micro-
architectural properties, DPPIV activity, and vessel protein were
determined using independent samples t-tests. One-way multivariate
analyses of variance were performed (EC50 and slope) for the respec-
tive cumulative concentration response curves to detect differences in
R652 ESTRADIOL SUPPLEMENTATION AND NPY NEUROTRANSMISSION
AJP-Regul Integr Comp Physiol • doi:10.1152/ajpregu.00072.2012 • www.ajpregu.org
atRBDraughonLibraryonMay13,2013http://ajpregu.physiology.org/Downloadedfrom
5. vasomotor response. The criteria for determining statistical signifi-
cance (␣ ϭ 0.05) was the same for all comparisons.
RESULTS
Animal characteristics. OVE (n ϭ 17) rats had substantially
larger uteri (Fig. 1A; OVE: 933 Ϯ 17 mg, OVX: 185 Ϯ 5 mg,
P Ͻ 0.05) and lower body weights at the conclusion of the
8-wk period (Fig. 1B; OVE: 201 Ϯ 3 g, OVX: 230 Ϯ 3 g, P Ͻ
0.05) compared with OVX (n ϭ 17). Estradiol supplementation
significantly enhanced bone volume-to-total volume ratio in
the OVE group versus OVX group by augmenting (P Ͻ 0.05)
trabecular thickness and number (Table 1). Furthermore, there
was a tendency (P ϭ 0.07) for augmented trabecular separation
in the OVE group versus OVX group. These data support a
difference in estradiol status between OVE and OVX groups.
NPY overflow and metabolism. Absolute NPY overflow be-
fore field stimulation (control baseline) did not differ between
groups (OVX: 2.86 Ϯ 0.54 ng/ml; OVE: 2.12 Ϯ 0.47 ng/ml).
NPY overflow increased over and above baseline values follow-
ing field stimulation in OVX and OVE rats (Fig. 2). NPY
overflow exhibited a gradual increase with the greatest concen-
tration detected at 30 s postfield stimulation (OVX: 0.24 Ϯ 0.14
ng/ml; OVE: 0.04 Ϯ 0.02 ng/ml).
The enzymatic breakdown of NPY can impact the physio-
logical response as only the full-length peptide stimulates
vasoconstriction. The DPPIV inhibitor diprotin A was added to
the vessel bath to determine the effects of DPPIV activity on
NPY bioavailability according to estradiol status. Absolute
NPY overflow with DPPIV inhibition (DPPIV baseline) before
field stimulation was similar across groups (OVX: 3.44 Ϯ 0.56
A
OVX OVE
0
50
100
150
200
250
*
*
BodyWeight(g)
B
OVX OVE *
Fig. 1. Animal characteristics: uterine weight (A) and body
weight (B). Rats with estradiol supplementation (OVE: n ϭ
17) had larger uteri and lower body weight compared with
their ovariectomized (OVX: n ϭ 17) counterparts. Bars
indicate means Ϯ SE. *Significant difference from OVX
(P Ͻ 0.05).
Table 1. Microarchitectural properties of the femoral distal
metaphysis
OVX OVE
BV/TV, % 2.8 Ϯ 0.8 12.4 Ϯ 1.4*
Tb.Th, m 21.5 Ϯ 2.4 29.3 Ϯ 1.8*
Tb.N, mm 1.2 Ϯ 0.3 4.6 Ϯ 0.7*
Tb.Sp, m 1314.0 Ϯ 516.2 213.5 Ϯ 37.8†
Values represent means Ϯ SE. OVX, ovariectomized; OVE, ovariectomized
and receiving 17-estradiol; BV/TV, bone volume-to-total volume ratio;
Tb.Th, trabecular thickness; Tb.N, trabecular number; Tb.Sp, trabecular sep-
aration. *P Ͻ 0.05 vs. OVX group, †P Ͻ 0.10 vs. OVX group.
Fig. 2. Neuropeptide Y (NPY) overflow in gastrocnemius first-order arterioles
of OVX (n ϭ 9) and OVE (n ϭ 11) rats. NPY overflow was greater with
DPPIV inhibition (diprotin A) compared with control condition regardless of
estradiol status. Bars indicate means Ϯ SE. *Significant difference from
control conditions (baseline, 0 s, and 30 s; P Ͻ 0.05).
R653ESTRADIOL SUPPLEMENTATION AND NPY NEUROTRANSMISSION
AJP-Regul Integr Comp Physiol • doi:10.1152/ajpregu.00072.2012 • www.ajpregu.org
atRBDraughonLibraryonMay13,2013http://ajpregu.physiology.org/Downloadedfrom
6. ng/ml; OVE: 2.56 Ϯ 0.66 ng/ml). DPPIV inhibition resulted in
an increase in NPY overflow at 0 s (OVX: 0.60 Ϯ 0.29 ng/ml;
OVE: 0.58 Ϯ 0.23 ng/ml) and 30 s (OVX: 0.37 Ϯ 0.20 ng/ml;
OVE: 0.46 Ϯ 0.18 ng/ml) following field stimulation in both
groups (Fig. 2: P Ͻ 0.05).
Whole vessel homogenates were analyzed to directly assess
DPPIV activity (Fig. 3). DPPIV activity did not differ between
OVX (19.37 Ϯ 0.21 mol·lϪ1
·minϪ1
, n ϭ 13) and OVE rats
(19.39 Ϯ 0.18 mol·lϪ1
·minϪ1
, n ϭ 15). Total vessel protein
content was quantified to rule out the possibility of differences
in enzyme activity with respect to vascular smooth muscle.
Arteriole protein content did not differ between OVX (39.72 Ϯ
0.45 g/ml) and OVE (39.37 Ϯ 0.40 g/ml) groups. DPPIV
activity was similar between groups, and its proteolytic actions
played an integral role in modulating the bioavailability of
NPY regardless of estradiol status in this young-adult cohort.
NPY vasomotor response. Diameter measurements of red
gastrocnemius first-order arterioles at resting and maximal
vasoconstriction conditions did not differ between OVX
(282.43 Ϯ 12.28 m and 110.08 Ϯ 6.89 m, respectively) and
OVE (293.56 Ϯ 8.61 m and 96.15 Ϯ 4.48 m, respectively)
rats. The cumulative concentration response curves were per-
formed to determine the effects of long-term estradiol supple-
mentation on Y1-receptor activity in skeletal muscle arterioles.
The Y1-receptor agonist [Leu31Pro34]NPY elicited a decrease
in vessel diameter that was 69% of maximum vasoconstriction
(Fig. 4) at the highest concentration tested. Estradiol status did not
affect the maximum amount of Y1-mediated vasoconstriction
with OVE (69 Ϯ 9% of maximum vasoconstriction; n ϭ 9)
producing similar magnitudes of vasoconstriction to that observed
in OVX (69 Ϯ 10% of maximum vasoconstriction; n ϭ 7). The
sensitivity of Y1-receptor actions did not differ between OVE
(EC50: Ϫ8.75 Ϯ 0.18 log M [Leu31Pro34]NPY; Hill slope:
Ϫ1.11 Ϯ 0.25% maximum vasoconstriction (%max VC)/log M
[Leu31Pro34]ϾNPY) and OVX rats (EC50: Ϫ8.63 Ϯ 0.10 log M
[Leu31Pro34]NPY; Hill slope: Ϫ1.65 Ϯ 0.34% max VC/log
M [Leu31Pro34]NPY).
A final set of cumulative concentration response curves was
performed to assess the effects of estradiol supplementation on
Y1-receptor-mediated potentiation of adrenergic vasoconstric-
tion. OVE (n ϭ 12; EC50: Ϫ6.31 Ϯ 0.19 log M NE; slope:
Ϫ1.19 Ϯ 0.21% max VC/log M NE) did not differ from OVX
(n ϭ 13; EC50: Ϫ6.16 Ϯ 0.19 log M NE; slope: Ϫ1.28 Ϯ
0.28% max VC/log M NE) in NE-stimulated vasoconstriction
(Fig. 5). Interestingly, neither OVE (n ϭ 11; EC50: Ϫ6.40 Ϯ
0.14 log M NE; slope: Ϫ0.78 Ϯ 0.14% maximum vasocon-
striction/log M NE) nor OVX (n ϭ 10; EC50: Ϫ6.18 Ϯ 0.20 log
M NE; slope: Ϫ1.34 Ϯ 0.34% maximum vasoconstriction/log M
NE) exhibited NPY potentiation via [Leu31Pro34]NPY of
NE-stimulated vasoconstriction (Fig. 6).
DISCUSSION
The purpose of this study was to examine the effects of
estradiol on NPY overflow, metabolism, and Y1-mediated vaso-
constriction in red gastrocnemius first-order arterioles. We found
that NPY overflow in ovariectomized rats was detectable and was
strongly inhibited by dipeptidyl peptidase IV activity. However,
estradiol replacement did not alter NPY overflow or inhibition by
dipeptidyl peptidase IV. Y1-receptor-mediated vasoconstriction
occurred in first-order arterioles of ovariectomized rats but was
not influenced by estradiol replacement. Although estradiol did
not affect these measures of NPY neurotransmission, estradiol
supplementation in this study significantly influenced variables
that are known to be responsive to estradiol such as body weight
(12, 37), uterine weight (21, 35), and bone morphology (4, 36, 43,
46). The estradiol dosage was similar to dosages used in other
studies that detected estradiol effects on vascular physiology (15,
42). To our knowledge this is the first study to directly evaluate
the role of estradiol in mediating NPY overflow, metabolism and
Fig. 3. DPPIV activity in gastrocnemius first-order arterioles of OVX (n ϭ 13)
and OVE (n ϭ 15) rats. Estradiol supplementation did not influence DPPIV
activity. Bars indicate means Ϯ SE.
Fig. 4. Cumulative concentration response curve for Y1-receptor agonist.
[Leu31Pro34]NPY-mediated vasoconstriction was similar in OVX (n ϭ 7) and
OVE (n ϭ 9) rats. Bars indicate means Ϯ SE.
Fig. 5. Cumulative concentration response curve for ␣-adrenergic receptor
agonist. Norepinephrine-mediated vasoconstriction did not differ between
OVX (n ϭ 13) and OVE (n ϭ 12) rats. Bars indicate means Ϯ SE.
R654 ESTRADIOL SUPPLEMENTATION AND NPY NEUROTRANSMISSION
AJP-Regul Integr Comp Physiol • doi:10.1152/ajpregu.00072.2012 • www.ajpregu.org
atRBDraughonLibraryonMay13,2013http://ajpregu.physiology.org/Downloadedfrom
7. Y1-mediated vasoconstriction. We found that estradiol replace-
ment in ovariectomized rats does not affect any of these variables
in the red gastrocnemius first-order arteriole.
NPY overflow. Our lab previously detected low levels (Ͻ0.05
ng/ml) of NPY overflow following field stimulation in adult,
ovary-intact rat skeletal muscle arterioles (8). While characteris-
tics related to NPY overflow have received little attention, there
was evidence to suggest that estradiol depletion led to an increase
in NPY content of skeletal muscle tissue (15). The present results
indicate that long-term estradiol supplementation does not influ-
ence NPY overflow from red skeletal muscle arterioles of ovari-
ectomized rats. Indeed, NPY overflow patterns in ovariectomized
(OVX and OVE) rats were similar to those previously observed in
ovary-intact rats (8). Furthermore, these results are congruent with
norepinephrine release data in rat tail artery, which was indepen-
dent of sex steroid influences (9).
Estradiol affects the expression of many vascular proteins
(30); therefore, it was plausible that estradiol was an underly-
ing mechanism behind the sex differences observed in some
measures of NPY neurotransmission (16, 17). The contrary
results of the current study versus those using whole muscle
homogenate may be attributed to several factors. First, whole
muscle homogenates do not discriminate between vessel type
(arteries, veins, capillaries, venules); thus it is difficult to pin
down the source behind the differences in NPY content. Whole
muscle homogenate will also include blood elements that
contain NPY originating from nonneural sources (platelets,
adrenal gland). One or more of these sources may be sensitive
to estradiol supplementation, which could affect the expression
of NPY and subsequent detection. The present study possesses
experimental control for extraneous sources of NPY such as
those related to blood elements. Therefore, the NPY concen-
tration recorded is indicative of the NPY overflow character-
istic of an isolated red skeletal muscle first-order arteriole,
which appears to be independent of estradiol supplementation.
DPPIV activity. Our data indicate that low levels of NPY
detection in young adult female rats occur, in part, as a product
of high protease activity under normal physiological condi-
tions. Once DPPIV activity is marginalized, NPY concentra-
tion rises significantly over baseline levels in both OVX and
OVE rats. This effect was irrespective of estradiol status; and
it was consistent with previous observations in ovary-intact
female rats, which exhibited a similar increase in NPY over-
flow with DPPIV inhibition (8).
The actions of DPPIV can significantly impact the response
initiated by NPY. In female rat tail artery, peptidase inhibition in
combination with exogenous NPY increased adrenergic vasocon-
striction following transmural nerve stimulation, whereas the
same condition had no effect on adrenergic vasoconstriction in
ovariectomized rats (10). Similarly, peptidase inhibition resulted
in decreased blood flow in hind leg conduit arteries of female rats
(17). The present findings fail to support a link between long-term
estradiol supplementation and NPY metabolism in red skeletal
muscle first-order arterioles. While no effect was observed with
estradiol supplementation, the results do reveal some interesting
developments in our concept of NPY in the vasculature.
The physiological significance of an augmented role for
DPPIV in the female rat resistance vasculature is that female
rats would have less Y1-receptor actions, and therefore, less
NPY-mediated vasoconstriction. Systemic blood pressure is
maintained, in part, through the actions of arterioles, which
control blood flow into the capillary beds (40). While it is
difficult to determine the role of DPPIV activity in influencing
blood flow through the resistance vasculature, the present
results do suggest a significant role for DPPIV in modulating
the amount of bioavailable NPY.
The stark similarities in DPPIV activity through direct (enzy-
matic assay) and indirect (NPY assay following DPPIV inhibi-
tion) measurements provide evidence to support the idea that
estradiol supplementation does not affect DPPIV mechanisms in
first-order arterioles. Prior study of whole skeletal muscle failed to
detect a difference in DPPIV activity with 2 wk of estradiol
supplementation (15). A unique addition of the present study was
to extend DPPIV analysis directly to isolated first-order arterioles.
Although DPPIV is active in modulating NPY in red skeletal
muscle first-order arterioles of young adult female rats, it is
independent of influences related to long-term estradiol supple-
mentation.
NPY vasoconstriction. The efficacy of NPY as a vasocon-
strictor depends on the level (artery, arteriole) and location
(mesentery, brain, skeletal muscle) of the vasculature under
study. Very little is known about the behavior of NPY in the
skeletal muscle arterioles of female rats. A prior study (18) of
male skeletal muscle arterioles revealed an inverse relationship
between the magnitude of vasoconstriction (vessel diameter
A
B
Fig. 6. Cumulative concentration response curves for ␣-adrenergic vasocon-
striction in the presence of a Y1-receptor agonist in OVE (A: n ϭ 11) and OVX
rats (B: n ϭ 10). [Leu31Pro34]NPY failed to potentiate norepinephrine-
mediated vasoconstriction in OVX and OVE rats. Bars indicate means Ϯ SE.
R655ESTRADIOL SUPPLEMENTATION AND NPY NEUROTRANSMISSION
AJP-Regul Integr Comp Physiol • doi:10.1152/ajpregu.00072.2012 • www.ajpregu.org
atRBDraughonLibraryonMay13,2013http://ajpregu.physiology.org/Downloadedfrom
8. changes) and vessel size (first-, second-, third-order arterioles).
In the current study, the amount of vasoconstriction observed
in female rat skeletal muscle first-order arterioles was similar
to previous measurements of the same vessel type observed in
males (18). The cornerstone of the present study was the
long-term effect of estradiol on NPY neurotransmission. The
available studies on sex differences (16–17) in NPY neu-
rotransmission implicate sex hormone status as a possible
candidate for the underlying difference between male and
female rats. The present data fail to support a link with respect
to estradiol supplementation and Y1-receptor activity as there
were no differences between OVX and OVE groups.
The absence of an estradiol effect on sympathetic neurotrans-
mission is not unprecedented with similar null results having been
observed in adrenergic vasoconstriction (3, 22, 29, 42). Estradiol
supplementation over a wide range of treatment durations
(ϳ1–60 days) did not alter the adrenergic postjunctional response
in female rats (3, 29, 42). The effects of estradiol supplementation
on NPY-mediated vasoconstriction are less clear and have re-
ceived little attention. In white vastus muscle, estradiol depletion
increased Y1-receptor protein expression and actions (15). How-
ever, estradiol depletion failed to change Y1-receptor protein in
red vastus muscle. It is possible that Y1 mechanisms are depen-
dent on the type of tissue (red or white muscle) or blood vessel
under study. Our results are consistent with other in vitro studies
that failed to detect a difference in sympathetic (adrenergic)
vasoconstriction following estradiol supplementation (3, 29, 42).
Y1-receptor activation can induce a moderate amount of vasocon-
striction in isolated first-order arterioles of young adult female
rats, and long-term estradiol supplementation does not impact
Y1-receptor sensitivity in these vessels.
NPY potentiation of adrenergic vasoconstriction. In many
vascular beds, NPY fails to cause direct vasoconstriction but
retains influence on vessel diameter through indirect effects,
most notably through potentiation of NE-induced vasoconstric-
tion at low concentrations (1–100 nmol/l) (1, 2, 13, 47). In the
present study, the Y1-receptor agonist did not potentiate NE-
mediated vasoconstriction in OVX and OVE groups. The
concentration used (98 nmol/l) was within the previously
mentioned range of concentrations where this Y1-receptor
agonist potentiates NE-mediated vasoconstriction (13, 28).
While the potentiation of adrenergic vasoconstriction is an
oft-described product of NPY in the vasculature (23), the lack
of potentiation in vessels that exhibit vasoconstriction to NPY
has been observed before (5, 14, 27). Moreover, this lack of a
contributory effect of NPY on adrenergic vasoconstriction in
these studies was noted in multiple animal models across
diverse vascular beds. In agreement with these findings, the
present results revealed a potent vasoconstrictor effect for NPY
with no discernible influence on adrenergic vasoconstriction in
isolated red skeletal muscle first-order arterioles of female rats.
Limitations. The enzymatic action of DPPIV results in a
C-truncated fragment of NPY. It is unclear as to the binding
capacity of the assay and the truncated product of DPPIV activity
(NPY3–36); however, we interpreted the increase in detectable
NPY as an increase in the bioavailability of the full-length peptide
based on the known actions of DPPIV with respect to NPY
metabolism. Some measures of NPY neurotransmission in skel-
etal muscle may depend on the type of muscle (red or white)
under study (15). The present study was concerned with a resis-
tance vessel that supplies primarily oxidative muscle (6). It is
unknown if NPY neurotransmission of white gastrocnemius first-
order arterioles is responsive to estradiol supplementation.
Conclusions. In young adult female rats, long-term estradiol
supplementation did not influence NPY overflow, breakdown,
or Y1-receptor-mediated vasoconstriction in isolated skeletal
muscle first-order arterioles. NPY overflow was detected fol-
lowing field stimulation and increased with DPPIV inhibition
regardless of estradiol status. The putative postjunctional re-
ceptor for NPY, Y1, induced a moderate vasoconstrictive
response in young adult female rat resistance vessels.
Perspectives and Significance
The observation that estradiol promotes vasorelaxation through
modulation of endothelial nitric oxide synthase activity (31) un-
derscores the potential for sex steroids to influence physiological
processes beyond those associated with reproduction. Today,
there is a level of expedition to develop our understanding on the
vascular effects of sex steroids, specifically estradiol and proges-
terone, as subjects such as hormone replacement therapy become
more common and polarizing in an aging female population.
Cardiovascular risk increases with age for both males and fe-
males, and increased sympathetic nerve activity in the vasculature
is a contributor to age-related changes in blood pressure (32).
While limited evidence suggests that sex steroids such as estradiol
may attenuate various measures of NPY in females (15), the
collective data inclusive of data from the present manuscript
suggest that the influence of estradiol is variable and possibly
dependent on multiple factors (e.g., tissue type, vessel type).
Future research will require both functional and molecular com-
ponents to identify the vascular regions responsive to sex steroids
and the associated signaling mechanisms involved.
ACKNOWLEDGMENTS
The authors thank Ryan Bailey for technical assistance during the project.
GRANTS
This project was supported by the National Institute on Aging Grant
5R03AG-033245 and the Arkansas Biosciences Institute, the major research
component of the Arkansas Tobacco Settlements Proceeds Act of 2000.
DISCLOSURES
No conflicts of interest, financial or otherwise, are declared by the author(s).
AUTHOR CONTRIBUTIONS
Author contributions: K.W.E., A.J.S., R.P., and H.A.K. conception and
design of research; K.W.E., A.J.S., E.S., T.B., R.P., and H.A.K. performed
experiments; K.W.E., A.J.S., E.S., T.B., R.P., and H.A.K. analyzed data;
K.W.E., E.S., T.B., R.P., and H.A.K. interpreted results of experiments;
K.W.E., T.B., and R.P. prepared figures; K.W.E. drafted manuscript; K.W.E.,
A.J.S., E.S., T.B., R.P., and H.A.K. edited and revised manuscript; K.W.E.,
A.J.S., E.S., T.B., R.P., and H.A.K. approved final version of manuscript.
REFERENCES
1. Abel PW, Han C. Effects of neuropeptide Y on contraction, relaxation,
and membrane potential of rabbit cerebral arteries. J Cardiovasc Phar-
macol 13: 52–63, 1989.
2. Andriantsitohaina R, Stoclet JC. Enhancement by neuropeptide Y
(NPY) of the dihydropyridine-sensitive component of the response to
alpha 1-adrenoceptor stimulation in rat isolated mesenteric arterioles. Br J
Pharmacol 99: 389–395, 1990.
3. Brandin L, Bergstrom G, Manhem K, Gustafsson H. Oestrogen mod-
ulates vascular adrenergic reactivity of the spontaneously hypertensive rat.
J Hypertens 21: 1695–1702, 2003.
R656 ESTRADIOL SUPPLEMENTATION AND NPY NEUROTRANSMISSION
AJP-Regul Integr Comp Physiol • doi:10.1152/ajpregu.00072.2012 • www.ajpregu.org
atRBDraughonLibraryonMay13,2013http://ajpregu.physiology.org/Downloadedfrom
9. 4. Cai DJ, Zhao Y, Glasier J, Cullen D, Barnes S, Turner CH, Wastney
M, Weaver CM. Comparative effect of soy protein, soy isoflavones, and
17beta-estradiol on bone metabolism in adult ovariectomized rats. J Bone
Miner Res 20: 828–839, 2005.
5. Clarke J, Benjamin N, Larkin S, Webb D, Maseri A, Davies G.
Interaction of neuropeptide Y and the sympathetic nervous system in
vascular control in man. Circulation 83: 774–777, 1991.
6. Delp MD, Duan C. Composition and size of type I, IIA, IID/X, and IIB
fibers and citrate synthase activity of rat muscle. J Appl Physiol 80:
261–270, 1996.
7. Donoso MV, Brown N, Carrasco C, Cortes V, Fournier A, Huidobro-
Toro JP. Stimulation of the sympathetic perimesenteric arterial nerves
releases neuropeptide Y potentiating the vasomotor activity of noradren-
aline: involvement of neuropeptide Y-Y1 receptors. J Neurochem 69:
1048–1059, 1997.
8. Evanson KW, Stone AJ, Hammond AL, Kluess HA. Neuropeptide Y
overflow and metabolism in skeletal muscle arterioles. J Physiol 589:
3309–3318, 2011.
9. Garcia-Villalon AL, Buchholz JN, Duckles SP, Krause DN. Noradren-
aline content and release in male and female rat tail arteries. J Cardiovasc
Pharmacol 29: 93–96, 1997.
10. Glenn TC, Krause DN, Duckles SP. Vascular responses to neuropeptide
Y are greater in female than male rats. Naunyn Schmiedebergs Arch
Pharmacol 355: 111–118, 1997.
11. Gustafsson H, Nilsson H. Endothelium-independent potentiation by neu-
ropeptide Y of vasoconstrictor responses in isolated arteries from rat and
rabbit. Acta Physiol Scand 138: 503–507, 1990.
12. Haim S, Shakhar G, Rossene E, Taylor AN, Ben-Eliyahu S. Serum
levels of sex hormones and corticosterone throughout 4- and 5-day estrous
cycles in Fischer 344 rats and their simulation in ovariectomized females.
J Endocrinol Invest 26: 1013–1022, 2003.
13. Han S, Yang CL, Chen X, Naes L, Cox BF, Westfall T. Direct evidence
for the role of neuropeptide Y in sympathetic nerve stimulation-induced
vasoconstriction. Am J Physiol Heart Circ Physiol 274: H290–H294,
1998.
14. Hanko JH, Tornebrandt K, Hardebo JE, Kahrstrom J, Nobin A,
Owman C. Neuropeptide Y induces and modulates vasoconstriction in
intracranial and peripheral vessels of animals and man. J Auton Pharmacol
6: 117–124, 1986.
15. Jackson DN, Ellis CG, Shoemaker JK. Estrogen modulates the contri-
bution of neuropeptide Y to baseline hindlimb blood flow control in
female Sprague-Dawley rats. Am J Physiol Regul Integr Comp Physiol
298: R1351–R1357, 2010.
16. Jackson DN, Milne KJ, Noble EG, Shoemaker JK. Gender-modulated
endogenous baseline neuropeptide Y Y1-receptor activation in the
hindlimb of Sprague-Dawley rats. J Physiol 562: 285–294, 2005.
17. Jackson DN, Milne KJ, Noble EG, Shoemaker JK. Neuropeptide Y
bioavailability is suppressed in the hindlimb of female Sprague-Dawley
rats. J Physiol 568: 573–581, 2005.
18. Joshua IG. Neuropeptide Y-induced constriction in small resistance
vessels of skeletal muscle. Peptides 12: 37–41, 1991.
19. Kim D, Duran WR, Kobayashi I, Daniels AJ, Duran WN. Microcir-
culatory dynamics of neuropeptide Y. Microvasc Res 48: 124–134, 1994.
20. Lacroix JS. Adrenergic and non-adrenergic mechanisms in sympathetic
vascular control of the nasal mucosa. Acta Physiol Scand Suppl 581: 1–63,
1989.
21. LeBlanc AJ, Reyes R, Kang LS, Dailey RA, Stallone JN, Moningka
NC, Muller-Delp JM. Estrogen replacement restores flow-induced vaso-
dilation in coronary arterioles of aged and ovariectomized rats. Am J
Physiol Regul Integr Comp Physiol 297: R1713–R1723, 2009.
22. Luksha L, Poston L, Gustafsson JA, Aghajanova L, Kublickiene K.
Gender-specific alteration of adrenergic responses in small femoral arter-
ies from estrogen receptor-beta knockout mice. Hypertension 46: 1163–
1168, 2005.
23. Lundberg JM, Franco-Cereceda A, Lacroix JS, Pernow J. Neuropep-
tide Y and sympathetic neurotransmission. Ann NY Acad Sci 611: 166–
174, 1990.
24. Lundberg JM, Pernow J, Franco-Cereceda A, Rudehill A. Effects of
antihypertensive drugs on sympathetic vascular control in relation to
neuropeptide Y. J Cardiovasc Pharmacol 10, Suppl 12: S51–S68, 1987.
25. Lundberg JM, Rudehill A, Sollevi A, Theodorsson-Norheim E, Ham-
berger B. Frequency- and reserpine-dependent chemical coding of sym-
pathetic transmission: differential release of noradrenaline and neuropep-
tide Y from pig spleen. Neurosci Lett 63: 96–100, 1986.
26. Lundberg JM, Terenius L, Hokfelt T, Goldstein M. High levels of
neuropeptide Y in peripheral noradrenergic neurons in various mammals
including man. Neurosci Lett 42: 167–172, 1983.
27. Lundberg JM, Terenius L, Hokfelt T, Martling CR, Tatemoto K,
Mutt V, Polak J, Bloom S, Goldstein M. Neuropeptide Y (NPY)-like
immunoreactivity in peripheral noradrenergic neurons and effects of NPY
on sympathetic function. Acta Physiol Scand 116: 477–480, 1982.
28. McAuley MA, Westfall TC. Possible location and function of neuropep-
tide Y receptor subtypes in the rat mesenteric arterial bed. J Pharmacol
Exp Ther 261: 863–868, 1992.
29. Mehrotra S, Gupta S, Villalon CM, Boomsma F, Saxena PR, Maas-
senVanDenbrink A. Rat carotid artery responses to alpha-adrenergic
receptor agonists and 5-HT after ovariectomy and hormone replacement.
Headache 47: 236–246, 2007.
30. Miller VM, Duckles SP. Vascular actions of estrogens: functional impli-
cations. Pharmacol Rev 60: 210–241, 2008.
31. Moriarty K, Kim KH, Bender JR. Minireview: estrogen receptor-
mediated rapid signaling. Endocrinology 147: 5557–5563, 2006.
32. Narkiewicz K, Phillips BG, Kato M, Hering D, Bieniaszewski L,
Somers VK. Gender-selective interaction between aging, blood pressure,
and sympathetic nerve activity. Hypertension 45: 522–525, 2005.
33. Pernow J, Ohlen A, Hokfelt T, Nilsson O, Lundberg JM. Neuropeptide
Y: presence in perivascular noradrenergic neurons and vasoconstrictor
effects on skeletal muscle blood vessels in experimental animals and man.
Regul Pept 19: 313–324, 1987.
34. Pourageaud F, De Mey JG. Vasomotor responses in chronically hyper-
perfused and hypoperfused rat mesenteric arteries. Am J Physiol Heart
Circ Physiol 274: H1301–H1307, 1998.
35. Rachon D, Seidlova-Wuttke D, Vortherms T, Wuttke W. Effects of
dietary equol administration on ovariectomy induced bone loss in
Sprague-Dawley rats. Maturitas 58: 308–315, 2007.
36. Riggs BL, Khosla S, Melton LJ 3rd. Sex steroids and the construction
and conservation of the adult skeleton. Endocr Rev 23: 279–302, 2002.
37. Roepke TA. Oestrogen modulates hypothalamic control of energy ho-
meostasis through multiple mechanisms. J Neuroendocrinol 21: 141–150,
2009.
38. Scharpe S, De Meester I, Vanhoof G, Hendriks D, van Sande M, Van
Camp K, Yaron A. Assay of dipeptidyl peptidase IV in serum by
fluorometry of 4-methoxy-2-naphthylamine. Clin Chem 34: 2299–2301,
1988.
39. Schneider F, Bucher B, Schott C, Andre A, Julou-Schaeffer G, Stoclet
JC. Effect of bacterial lipopolysaccharide on function of rat small femoral
arteries. Am J Physiol Heart Circ Physiol 266: H191–H198, 1994.
40. Segal SS. Regulation of blood flow in the microcirculation. Microcircu-
lation 12: 33–45, 2005.
41. Small DL, Bolzon BJ, Cheung DW. Endothelium-independent potenti-
ating effects of neuropeptide Y in the rat tail artery. Eur J Pharmacol 210:
131–136, 1992.
42. Stice JP, Eiserich JP, Knowlton AA. Role of aging versus the loss of
estrogens in the reduction in vascular function in female rats. Endocrinol-
ogy 150: 212–219, 2009.
43. Syed F, Khosla S. Mechanisms of sex steroid effects on bone. Biochem
Biophys Res Commun 328: 688–696, 2005.
44. Tarnopolsky MA. Sex differences in exercise metabolism and the role of
17-beta estradiol. Med Sci Sports Exerc 40: 648–654, 2008.
45. Tatemoto K, Carlquist M, Mutt V. Neuropeptide Y–a novel brain
peptide with structural similarities to peptide YY and pancreatic polypep-
tide. Nature 296: 659–660, 1982.
46. Tivesten A, Moverare-Skrtic S, Chagin A, Venken K, Salmon P,
Vanderschueren D, Savendahl L, Holmang A, Ohlsson C. Additive
protective effects of estrogen and androgen treatment on trabecular bone
in ovariectomized rats. J Bone Miner Res 19: 1833–1839, 2004.
47. Vu HQ, Budai D, Duckles SP. Neuropeptide Y preferentially potentiates
responses to adrenergic nerve stimulation by increasing rate of contrac-
tion. J Pharmacol Exp Ther 251: 852–857, 1989.
48. Wahlestedt C, Grundemar L, Hakanson R, Heilig M, Shen GH,
Zukowska-Grojec Z, Reis DJ. Neuropeptide Y receptor subtypes, Y1
and Y2. Ann NY Acad Sci 611: 7–26, 1990.
49. Williams DA, Segal SS. Feed artery role in blood flow control to rat
hindlimb skeletal muscles. J Physiol 463: 631–646, 1993.
50. Xia J, Neild TO, Kotecha N. Effects of neuropeptide Y and agonists
selective for neuropeptide Y receptor sub-types on arterioles of the
guinea-pig small intestine and the rat brain. Br J Pharmacol 107: 771–776,
1992.
R657ESTRADIOL SUPPLEMENTATION AND NPY NEUROTRANSMISSION
AJP-Regul Integr Comp Physiol • doi:10.1152/ajpregu.00072.2012 • www.ajpregu.org
atRBDraughonLibraryonMay13,2013http://ajpregu.physiology.org/Downloadedfrom