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  1. 1. Você pode também dar baixa destes resumos dos CD-ROM´s, não apenas de Endocrinofisiologia mas de diversos outros assuntos de Fisiologia Humana (arquivos em *.pdf e/ou *.doc), com textos e ilustrações, diretamente do site: http://www.aw-bc.com/info/ip/assignments.html e escolha entre os seguintes assuntos: Muscular; Nervous I; Nervous II; Cardiovascular; Respiratory; Urinary ; Fluids & Electrolytes; Endocrine e Digestive System(novo) Veja também aulas online (DEMO dos CD-ROM´s): Cardiovascular system Digestive system (novo)
  2. 2. Veja, online, estas aulas, completas Segunda Parte: Actions of Hormones on Target Cells Graphics are used with permission of: Pearson Education Inc., publishing as Benjamin Cummings (http://www.aw-bc.com) Page 1. Actions of Hormones on Target Cells  Hormones influence their target cells by binding to specific receptors.  The hormone-receptor interaction initiates the process of transforming the chemical message into a cell response. Page 2. Goals/ What You Need to Know Goals  To learn about hormone receptors.  To describe common second messenger systems and transcription factors.  To review insulin.  To understand that hormones induce changes in cellular metabolism. What You Need to Know  That changing the shape of a molecule can activate or inactivate it.  The terminology of carbohydrate, lipid and protein metabolism.  The difference between the absorptive and postabsorptive states of the body. Page 3. Target Cell Responses to Hormones  Hormones bind with receptors to initiate the cellular response to a chemical signal.  Target cells convert the signal into a biochemical change inside the cell.  Via second messenger systems.  Via direct gene activation.  Cells respond to this stimulus in several different ways: 1. Cause contraction of muscle tissue. 2. Secretion of cellular products. 3. Effecting ion exchange through channels. 4. Cause synthesis of new peptides and proteins. 5. Cause breakdown of storage molecules.  Receptors are complex proteins that only respond to specific hormones.  Receptors for water-soluble hormones are found on the plasma membrane.  Receptors for lipid-soluble hormones are found in the cytoplasm or the nucleus.  Receptors will down- regulate and decrease sensitivity when there is prolonged exposure to high levels of a hormone.  Receptors have the ability to up-regulate and increase sensitivity in response to sustained low levels of a hormone.  Not all cells have receptors for all hormones and some cell respond differently to different concentrations of hormone. **Now is a good time to go to the quiz question #1.  Click the quiz button on the left side of the screen.  Click on the scrolling page list at the top of the screen and complete question 1.  When you are finished you can click the return from link button on the left side of the screen to return to the topic. Page 4. Water- soluble Hormones and Receptor Responses
  3. 3.  The water soluble hormones are the peptide and catecholamines.  They bind to receptors on the outside surface of the cell.  Two common classes of membrane bound receptors are: o Receptors that activate G-proteins. o Receptors that activate protein kinases. 1. G-protein moderated second messenger systems cAMP second messenger.  Hormone (first messenger) binds to receptor on outside of cell membrane.  Receptor changes shape and activates G-protein on inside of cell membrane.  GTP binds to G-protein and causes it to activate adenylate cyclase.  Adenylate cyclase converts ATP into cyclic AMP (cAMP ).  cAMP acts as a second messenger and phosphorylates kinases inside the cell.  The kinases can activate or inhibit activities of the cell.  The process continues as long as long as the G-protein is active.  Phosphodiesterase degrades cAMP and stops the process.  Amplification – greatly increases the effect that single hormone molecule has on the activity of a cell. DAG and IP 3 second messengers.  Diacylglycerol (DAG) and inositol triphosphate (IP3) are other G-protein moderated second messengers.  Hormone binds to receptor on outside of cell membrane which changes shape and stimulates the G-protein.  Activated G-protein binds to phospholipase C on inside of cell membrane.  Phospholipase C converts membrane phospholipids into DAG and IP3.  DAG remains in the cell membrane and activates protein kinase C which influences cell response.  IP3 causes the endoplasmic reticulum to release Ca++, which acts like a second messenger.  Ca++ can bind to the protein calmodulin and enhance the response of the cell. **Now is a good time to go to the quiz question #2.  Click the quiz button on the left side of the screen.  Click on the scrolling page list at the top of the screen and complete question 2.  When you are finished you can click the return from link button on the left side of the screen to return to the topic. 2. Receptors that activate protein kinases.  Some hormones bind with tyrosine kinase receptors on the outside of the cell membrane.  When two receptors are bound their interior surfaces intertwine which causes the phosphorylation of neighboring phosphate groups on the receptor.  The active phosphate sites provide a docking site for intracellular relay proteins.  The relay protein phosphorylates other kinases within the cell that causes the cellular response.  Catecholamines and insulin are water-soluble hormones that bind to plasma membrane receptors and are good examples of how hormones can have multiple and varied effects on their target tissues.
  4. 4. Now is a good time to go to the quiz question #3.  Click the quiz button on the left side of the screen.  Click on the scrolling page list at the top of the screen and complete question 3.  When you are finished you can click the return from link button on the left side of the screen to return to the topic. Page 5. Insulin Review *Be sure to view all the steps in the animation on this page and make notes in the space provided below.  Secretion  Transport
  5. 5.  Cellular Mechanism of Action  Synthesis  Functions  Breakdown ** Now is a good time to go to the quiz question #4.  Click the quiz button on the left side of the screen.  Click on the scrolling page list at the top of the screen and complete question 4.  When you are finished you can click the return from link button on the left side of the screen to return to the topic. Page 6. Diabetes Mellitus  There are two types of diabetes mellitus: 1. Type I – characterized by insulin deficiency or absence. 2. Type 2 –characterized by normal or elevated insulin levels, but resistance of target cells to insulin.  Complete the table exercise and then fill in the blanks in the copy of the same chart below. 1 4 3 2  Be sure to also click on the muscle and adipose tissue to see other ways in which insulin secretion can be affected. Page 7. Lipid- soluble Hormones  The lipid-soluble hormones are steroids and TH.
  6. 6.  Receptors are located inside cells, typically inside the nucleus.  Each receptor has a site that binds to the hormone and a site that binds to DNA.  The DNA site is covered by a chaperone molecule when no hormone is present.  When a hormone binds the chaperone is released and the hormone receptor complex binds to DNA and acts as a transcription factor.  The hormone receptor complex can trigger the synthesis of mRNA and stimulate or it can inhibit gene activity.  If mRNA is stimulated then new proteins will be synthesized.  Cortisol  Cortisol binds with receptors in the nucleus.  The hormone-receptor complex acts as a transcription factor.  Thyroid Hormone  T4 is converted into T3 inside cells.  T3 receptors are located on the DNA in the nucleus. Now is a good time to go to the quiz question #5.  Click the quiz button on the left side of the screen.  Click on the scrolling page list at the top of the screen and complete question 5.  When you are finished you can click the return from link button on the left side of the screen to return to the topic. Page 8: Summary
  7. 7.  Hormone receptors are proteins located in the plasma membrane or the interior of the cell.  Water-soluble hormones bind to plasma membrane receptors, and lipid-soluble hormones typically bind to intracellular receptors.  Receptor activation engages cellular machinery that leads to the response of the cell.  The effects of a single molecule of hormone are amplified by the cellular machinery.  All about insulin, diabetes mellitus, and the causes and consequences of hypersecretion of insulin. Notes on Quiz Questions: Quiz Question #1: Hormone Receptors  The first part of this question requires you to place hormone receptors in their correct positions on the cell membrane or inside the cell.  The second part of this question asks you to pick which receptors are for water-soluble hormones and which receptors are for lipid-soluble hormones. Quiz Question #2: Second Messenger Systems  This question requires you to put the events that lead to a cell response in the correct chronological order. Be sure to review the action of plasma membrane receptors before answering this question. Quiz Question #3: Insulin  This question requires you to put the events that occur when insulin binds with its receptors in the correct order. Quiz Question #4: Insulin vs. Glucagon  You must complete a table that contrasts the antagonistic effects of insulin and glucagon.  Take note that there are two pages to this table. Quiz Question #5: Steroid Hormones  You must put the elements of a steroid based hormone response in the correct sequence. Study Questions on Action of Hormones and Hormone Receptors 1. (Page 1.) How do hormones influence their target cells? 2. (Page 3.) What are the two ways in which the chemical message of a hormone is converted into a cell response inside the cell? 3. (Page 3.) List the 5 ways in which cells respond to activation by hormones. a. b. c. d. e. 4. (Page 3.) Receptors for water-soluble hormones are found on the _____________ of target cells, while receptors for lipid-soluble hormones are found in the ________ or________ of cells. 5. (Page 3.) Target cells tend to ______ _______ the number of their receptors when there are sustained high levels of hormone present. 6. (Page 3.) True or False: All cells have receptors for all hormones.
  8. 8. 7. (Page 4.) Put the steps of the cAMP second messenger system in the correct chronological sequence. 1. G-protein binds to adenylate cyclase which converts ATP into cAMP. 2. Activated protein kinases elicit the cell response. 3. Hormone binds with Receptor. 4. cAMP phosphorylates protein kinases. 5. Receptor changes shape and activates G-protein. 8. (Page 4.) ______________ is the process whereby a single hormone can elicit the response of many second messengers within single target cell. 9. (Page 4.) Complete this sequence: hormonereceptorG-protein______________ IP3 and ____ . 10. (Page 4.) When insulin binds to a tyrosine kinase receptor on its target cell what is the main result? 11. (Page 5.) List the main stimuli for insulin secretion. a. b. c. d. 12. (Page 5.) How is insulin transported through the blood? 13. (Page 5.) What are the two major functions of insulin? 14. (Page 6.) ________ diabetes is characterized by insulin absence or deficiency, while ________ diabetes is caused by resistance of target cells to the action of insulin. 15. (Page 6.) Excess glucose in the urine is known as __________ 16. (Page 7) When a lipid soluble hormone binds to its receptor molecule it acts as a 17. (Page 7) Put these events in the correct chronological sequence. 1. mRNA is transcribed. 2. New protein is synthesized in the cell. 3. Cortisol binds to receptor-chaperone complex. 4. Hormone-receptor complex binds to DNA. 5. Cell response is initiated.
  9. 9. Hypothalamic- Pituitary Axis Graphics are used with permission of: Pearson Education Inc., publishing as Benjamin Cummings (http://www.aw-bc.com) Page 1. Introduction  The hypothalamus and pituitary gland form a complex interface between the nervous system and the endocrine system.  The brain can influence the activity of Neurosecretory cells and hormones can influence the release of other hormones. Page 2. Goals/ What You Need to Know Goals  To study the hypothalamic-pituitary axis anatomy.  To review the hypophyseal portal system.  To identify sources of endocrine and neural control of the hypothalamic-pituitary axis.  To review thyroid hormone. What You Need to Know  The difference between a neurotransmitter and a hormone.  The difference between somatic and autonomic nervous systems.  The role of the hypothalamus in the control of the autonomic nervous system.  Also known as the hypophysis. Page 3. Pituitary Anatomy  Also known as the hypophysis.  Divided into the glandular anterior lobe and the neuronal posterior lobe.  Anterior lobe is also known as the adenohypophysis.  Posterior lobe is also known as the neurohypophysis.  The pituitary is connected to the hypothalamus via a stalk of tissue called the infundibulum. Anterior Pituitary  The six major anterior pituitary hormones are peptides.  The Six Major Anterior pituitary hormones are: 1. Thyroid Stimulating Hormone (TSH or thyrotropin) 2. Follicle Stimulating Hormone (FSH, a gonadotropin) 3. Luteinizing Hormone (LH, a gonadotropin) 4. Adrenocorticotropic Hormone (ACTH, or corticotropin) 5. Growth Hormone (GH) 6. Prolactin (PRL)  Targets and Functions of the Anterior Pituitary Hormones 1. TSH – target thyroid gland and stimulates secretion of thyroid hormone (TH). 2. FSH – targets follicles in the ovaries of females and stimulates growth of follicle and production of estrogen. In males it targets the testes and stimulates sperm cell production. 3. LH – targets follicle, triggers ovulation and increases secretion of progesterone. In males it stimulates testosterone production. 4. ACTH – targets the adrenal cortex and causes the secretion of glucocorticoids. 5. GH - targets most bodily tissues and stimulates metabolism and growth of those tissues. 6. PRL - targets the breasts in females. Stimulates breast development and lactation.  Of the six anterior pituitary hormones, four directly stimulate other endocrine glands and are known as tropic hormones .  For each target gland/tissue here fill in the correct anterior pituitary hormone.  Also make sure to highlight the four tropic hormones.
  10. 10.  The anterior pituitary gland is connected to the hypothalamus via the hypophyseal portal system.  Capillaries in the ventral hypothalamus pick up hormones released by hypothalamic neurons and transport them to the capillaries of the anterior pituitary. Posterior Pituitary  Is composed primarily of neuronal tissue.  Is connected to the supraoptic and paraventricular nuclei of the hypothalamus via axons in the infundibulum.  Stores two major neurohormones for later release. 1. ADH (vasopressin) – stimulates water reabsorption by kidneys. 2. Oxytocin – stimulates labor contractions during birth.  Release of posterior pituitary and hypothalamic hormones is identical to neurotransmitter release by other neurons.  Molecules that function as hormones in the hypothalamic-pituitary axis are often neurotransmitters, neuromodulators, or paracrines in other places in the body. **Now is a good time to go to the quiz questions #1&2.  Click the quiz button on the left side of the screen.  Click on the scrolling page list at the top of the screen and complete questions 1&2.  When you are finished you can click the return from link button on the left side of the screen to return to the topic. Page 4. Hypothalamic Hormones  Are the first in a series of hormones that ultimately leads to the secretion of hormones by specific endocrine glands.  Several of the hypothalamic hormones stimulate tropic hormones in the anterior pituitary.  Observe the following diagram closely to see how hypothalamic hormones influence the regulation of secretions of other endocrine glands.
  11. 11.  For each hormone series, negative feedback loops control circulating levels of the target gland hormones.  Negative feedback from the target gland can be directed at the anterior pituitary, the ventral hypothalamus or both. TRH CRH ↓ ↓ TSH ACTH ↓ ↓ TH Cortisol  The hypothalamic hormones also maintain the anterior pituitary and the tropic hormones help to maintain their target endocrine glands.  In some instances hormones of one series will cause the secretion of the hormones of another series (i.e. TH stimulates secretion of GH).  Prolactin (PRL) is unique because its primary stimulus from the hypothalamus is inhibitory except after birth when milk production begins. **Now is a good time to go to the quiz questions #3 &4.
  12. 12.  Click the quiz button on the left side of the screen.  Click on the scrolling page list at the top of the screen and complete questions 3 &4.  When you are finished you can click the return from link button on the left side of the screen to return to the topic. Page 5. Hypothalamus, Autonomic Nervous System, and Neuroendocrine interactions  Parts of the cerebral cortex, limbic system, basal nuclei, reticular formation, and retina all project to the thalamus.  Strong emotions, ingestion of food, painful stimuli, trauma, infection, hot/cold extremes, and light input from the retina can influence the endocrine system through these hypothalamic circuits.  There are several examples of how the hypothalamus mediates endocrine responses. 1. Neuroendocrine reflexes  Suckling or crying can initiate the milk letdown reflex.  Sensory inputoxytocinmammary glandsmilk letdown. 2. Chemically sensitive neurons.  Osmoreceptors in hypothalamus are stimulated by high concentrations of solute in the blood.  This leads to synthesis and release of ADH.  ADH targets the kidneys and promotes the reabsorption of water. 3. Circadian rhythms  Some hormones exhibit daily fluctuations.  Input form the retina onto the hypothalamus is one way in which day/night hormones levels fluctuate.  Cortisol has pronounced high and low peaks throughout the day. **Now is a good time to go to the quiz question #6.  Click the quiz button on the left side of the screen.  Click on the scrolling page list at the top of the screen and complete question 6.  When you are finished you can click the return from link button on the left side of the screen to return to the topic. Page 6. Thyroid Hormone Review  Be sure to view all the steps in the animations on this page and make notes in the spaces provided below.  All of these concepts have been covered in other topics.
  13. 13.  Secretion  Transport  Cellular Mechanism of Action  Synthesis  Functions  Breakdown Page 7. Hypothyroidism and Hyperthyroidism  Diseases of the thyroid gland are common.  When viewing the symptoms of hyposecretion or hypersecretion keep in mind the metabolic effects that TH has on its target tissues.  Listed below are common symptoms of both hyposecretion and hypersecretion of TH.  Chronic hyposecretion can lead to myxedema .
  14. 14.  Chronic hypersecretion can be caused by tumors or an autoimmune disease known as Grave’s disease.  Diseases of the thyroid can be primary or secondary in nature  Primary disease is one in which the gland itself is affected.  Secondary Disease is when the anterior pituitary or the hypothalamus is not functioning properly.  Primary hypothyroidism can be caused by: 1. Failure of thyroid gland to secrete TH. 2. Lack of dietary iodine leads to insufficient TH production.  Secondary hypothyroidism can be caused by: 1. A lack of TSH or TRH due to pathology.  Primary hyperthyroidism can be caused by: 1. Tumor of thyroid gland. 2. Grave’s disease.  Secondary Hyperthyroidism can be caused by: 1. Excess secretion of the anterior pituitary or hypothalamus.  Keep in mind when reviewing this page that excesses of hypothalamic and pituitary hormones will have positive effect on thyroid gland and cause it to enlarge. A lack of hypothalamic or pituitary hormones will have negative effect on the size of the thyroid gland. **Now is a good time to go to the quiz question #5.  Click the quiz button on the left side of the screen.  Click on the scrolling page list at the top of the screen and complete question 5.  When you are finished you can click the return from link button on the left side of the screen to return to the topic. Page 8. Summary  Hypothalamic neurons produce hormones.  Some hypothalamic hormones enter the systemic circulation from the posterior pituitary gland and others influence the anterior pituitary via the hypophyseal portal system.  TSH, FSH, LH, ACTH, and GH from the anterior pituitary influence secretion of a third hormone from a target gland (tropic effects).  Target gland hormones can exert negative feedback control of the hypothalamus and/or anterior pituitary.  Neurons throughout the brain influence the hypothalamus.  All about thyroid hormone, and the causes and consequences of hypo- and hypersecretion of TH. Notes on Quiz Questions Quiz Question #1: Pituitary Anatomy and Hormones.  The first part of this question has you label the parts of the hypothalamus and pituitary gland.  The second part of this question requires you to place the posterior pituitary hormones where they are produced.  The third part of this question requires you to place the six anterior pituitary hormones on the diagram where they are produced.  The fourth part of this question requires you to identify the two inhibiting hypothalamic hormones.  The final part of this question requires you to place the hypothalamic hormones at their correct sites of production. Quiz Question #2: Hypothalamic and Pituitary Hormones
  15. 15.  The first part of this question requires you select eight hormones that are secreted directly into the systemic circulation by either the hypothalamus or the pituitary gland.  The second part of this question requires you to identify the hypophyseal portal veins. Quiz Question #3: Cortisol and Negative Feedback  This question requires you to use your knowledge of the negative feedback loop between CRHACTHCortisol.  You will be given a clinical problem and you must predict the results of the clinical tests that were administered. Quiz Question #4: Prolactin and Inhibition  This question deals with the unique relationship between prolactin and dopamine.  Remember that under normal circumstances prolactin secretion is inhibited. Quiz Question #5: Hypothyroidism  This question presents you with a clinical problem dealing with primary hypothyroidism.  Keep in mind that a primary disease is one in which the endocrine gland is not working properly. Use your knowledge of negative feedback to predict what will happen with treatment. Quiz Question #6: Circadian Rhythms  This question requires you to choose which events will upset the circadian rhythm.  Remember that your circadian rhythm is set by light/dark cycles. Study Questions on Endocrine System Review 1. (Page 3.) Label this figure Supraoptic nuclei Paraventricular nuclei Ventral nuclei Anterior pituitary Posterior pituitary Infundibulum 2. (Page 3.) What is the name of the specialized capillary system that connects the ventral hypothalamus to the anterior pituitary? 3. (Page 3.) Match the following hypothalamic hormones with their functions: TRH CRH GNRH DA ADH GHRH
  16. 16. __________ a. Inhibits production of prolactin __________ b. Stimulates secretion of FSH and LH __________ c. Triggers secretion of TSH __________d. Stimulates the secretion of GH __________e. Promotes water reabsorption by the kidneys __________f. Causes the secretion of ACTH 4. (Page 3.) What is a tropic hormone? 5. (Page 3.) What are the major tropic hormones of the anterior pituitary and what are their targets? 6. (Page 4.) High levels of cortisol due to injections of cortisone will have what effect on the secretion of CRH and ACTH? 7. (Page 4.) Lack of TSH would lead to a ___________ in TH. 8. (Page 4.) Why is secretion of PRL unique amongst hormones of the hypothalamic-pituitary axis? 9. (Page 4.) In general hormones of the hypothalamic-pituitary axis are maintained by a _________________ ___________________ mechanism. 10. (Page 5.) Which of the following would not influence the endocrine system via the hypothalamus? a. strong emotions b. bright lights c. painful stimuli d. infections e. all of the above would influence the endocrine system via the hypothalamus 11. (Page 5.) Hormones such as cortisol exhibit daily fluctuations that are part of our bodies normal __________ ___________. 12. (Page 6.) What are the main ingredients necessary for TH synthesis? 13. (Page 6.) True or False: TH binds with plasma membrane receptors. 14. (Page 6.) List several of the main functions of TH. 15. (Page 7.) Mental sluggishness can be a symptom of _______________. 16. (Page 7.) Grave’s disease is usually a primary/secondary disease of the thyroid gland. 17. (Page 7.) Excessive secretions of TSH from the anterior pituitary can lead to ___________ ____________.
  17. 17. Response to Stress Graphics are used with permission of: Pearson Education Inc., publishing as Benjamin Cummings (http://www.aw-bc.com) Page 1. Introduction  When there is an overwhelming threat to the body the nervous and endocrine systems produce a well-coordinated, generalized response designed to ensure the health of the individual. Page 2. Goals/ What You Need to Know Goals  To understand stress in terms of endocrine function.  To learn how the nervous system directs a generalized nonspecific response to stress.  To review epinephrine.  To review cortisol. What You Need to Know  The neural input to the hypothalamus.  The relationship between the hypothalamus and the autonomic nervous system.  The anatomy and function of the hypothalamic-pituitary axis. Page 3. Stress Response  Stressful situations put the body at risk and the body responds:  In individual ways to maintain homeostasis.  With a coordinated generalized nonspecific response called the stress response.  Increased levels of epinephrine, norepinephrine, and cortisol are indicators that the body is under stress.  Stressors are any stimuli that put the body at risk and stimulate the release of the stress response hormones.  Stressors include:  Prolonged exposures to temperature extremes  Heavy exercise  Fright  Surgery  Emotional Stress (happy or unhappy) **Now is a good time to go to the quiz question #1.  Click the quiz button on the left side of the screen.  Click on the scrolling page list at the top of the screen and complete question 1.  When you are finished you can click the return from link button on the left side of the screen to return to the topic. Page 4. Hypothalamus and Stress Response  The hypothalamus directs the body’s stress response.  The nervous system sends input about stressful conditions to the hypothalamus which then engages both the nervous and endocrine systems in the stress response.  Fight or Flight response.
  18. 18. The hypothalamus stimulates the sympathetic portion of the ANS and the endocrine system via the adrenal glands during the fight-or-flight response.  Sympathetic responses include:  Increases in cardiac output  Increases in ventilation  Changes in blood pressure  Redirection of blood flow to skeletal muscle and peripheral blood vessels  Increases in sweating  Epinephrine responses include:  Enhancing the sympathetic responses outlined above  Mobilizes carbohydrate stores by synthesizing new glucose and breaking down fats  Prolonged Response  Occurs at least 30 minutes after exposure to stressors.  Cortisol secretion by the adrenal cortex increases in the following pattern:  CRHACTHCortisol  Effects of cortisol include:  Mobilization of energy by breaking down glycogen, fats, and through the synthesis of new glucose by the liver.  Release of amino acids by skeletal muscle which can be used to repair damaged tissues.  Vasoconstriction of vessels such as those of the digestive organs.  Inhibition of inflammation and the immune response.  Additional Hormones  ADH – helps maintain vasoconstriction and therefore blood pressure.  Aldosterone – helps to maintain blood pressure and blood volume during the stress response.
  19. 19. Page 5. Epinephrine Review  Be sure to view all the steps in the animations on this page and make notes in the spaces provided below.  All of these concepts have been covered in other topics.  Secretion  Transport  Cellular Mechanism of Action  Synthesis  Functions  Breakdown Page 6. Epinephrine: Hyposecretion vs. Hypersecretion  Hyposecretion  There are no known pathologies associated with hyposecretion of the adrenal medulla.  This may be due in part to the fact that sympathetic nervous system can replace activities of the adrenal catecholamines.  Hypersecretion  In rare cases a tumor called a pheochromacytoma secretes large amounts of catecholamines and is not under the control of the sympathetic nervous system.  Symptoms of hypersecretion include: o High BP o Palpitations o Rapid heart rate o Excessive sweating o High Blood Glucose  This rare condition is usually treated with surgery and normal adrenal medulla function resumes.
  20. 20. Page 7. Cortisol Review  Be sure to view all the steps in the animations on this page and make notes in the spaces provided below.  All of these concepts have been covered in other topics.  Secretion  Transport  Cellular Mechanism of Action  Synthesis  Functions  Breakdown **Now is a good time to go to the quiz questions #2- 4  Click the quiz button on the left side of the screen  Click on the scrolling page list at the top of the screen and complete questions 2-4.  When you are finished you can click the return from link button on the left side of the screen to return to the topic. Page 8. Cortisol: Hypersecretion vs. Hyposecretion
  21. 21.  Problems in the adrenal cortex can arise from primary sources (those in which the adrenal gland fails) and secondary sources (problems arising from the anterior pituitary or hypothalamus).  Hypersecretion.  Cushing’s disease – often caused by a pituitary tumor.  Cushing’s syndrome – caused by over administration of glucocorticoids drugs.  Signs and symptoms include:  Moon-shaped face and ‘buffalo hump’ on back due to redistribution of fat  Hyperglycemia – sometimes leading to diabetes mellitus  High BP  Spindly limbs, easy bruising and poor healing  Overly susceptible to infections  Hyposecretion.  Addison’s disease – caused by destruction of adrenal gland or pituitary damage.  Signs and Symptoms include:  Bronzed skin  Hypoglycemia  Low BP  Decreased levels of NA+, dehydrations, salt cravings - due to lack of aldosterone  Treatment.  Cushing’s:  Removal of tumor.  Readjustment of drug dosages.  Addison’s:  Replacement of cortisol and aldosterone. Page 9. Summary  The stress response is mediated at first by the sympathetic nervous system and epinephrine and later by cortisol.  The stress response protects the body from harm and ensures survival.  All about epinephrine and cortisol, and the causes and consequences of hypo- and hypersecretion of each. Notes on Quiz Questions Quiz Question #1: Stress Response  This question requires you to choose all the aspects of the stress response.  There are several correct responses, not just one. Quiz Question #2: Rapid vs. Prolonged Response  This question requires you to place the correct hormones and descriptions into the proper categories.  Be sure to do the pages that review epinephrine and cortisol before doing this question. Quiz Question #3: Cortisol and Negative Feedback  You must choose the symptoms associated with the stress response.  In the second part you must choose all the hormones associated with the stress response. Quiz Question #4: Stress and Stress Hormones  This question leads you through a series of questions that review the functions of the stress response and the stress hormones. Study Questions on the Stress Response 1. (Page 1.) True or False: The stress response involves only the endocrine system. 2. (Page 3.) List the five stressors that were introduced on this page. 1.
  22. 22. 2. 3. 4. 5. 3. (Page 4.) Below is a list of responses to stressful stimuli. Next to each item mark whether it is part of the rapid response (R) or the prolonged response (P), or both (B). _____ increased cardiac output _____ release of amino acids by skeletal muscle _____ gluconeogenesis in the liver _____ increases in blood pressure _____ inhibition of the immune response _____ increased ventilation _____ the ‘fight or flight’ response 4. (Page 4.) What is the main stimulus for secretion of adrenal medulla hormones? 5. (Page 4.) How do ADH and aldosterone aid in the stress response? 6. (Page 5.) How is epinephrine transported in the blood? 7. (Page 5.) What is the unique feature of epinephrine synthesis that allows it to enter the circulation so quickly? 8. (Page 6.) True or false: There are many more pathologies associated with hyposecretion of epinephrine than there are for hypersecretion. 9. (Page 6.) List the symptoms of hypersecretion or epinephrine as outlined on this page. a. b. c. d. e. 10. (Page 6.) Although rare, one of the more common causes for hypersecretion of the adrenal medulla is a ___________________. 11. (Page 7.) True or false: Cortisol is synthesized on an ‘as needed’ basis. 12. (Page 7.) How is cortisol transported through the blood, what effects does this have on its half-life? 13. (Page 7.) Where are cortisol receptors found in cells? 14. (Page 8.) What is the difference between Cushing’s disease and Cushing’s syndrome? 15. (Page 8.) Below is a list of symptoms, beside each symptom indicate whether it is related to hypo- or hypersecretion of adrenal cortex hormones. _____ Redistribution of body fat to places like the face and back of neck _____ Elevated BP _____ Bronzed skin _____ Overly susceptible to infections _____ Salt cravings due to hyponatremia _____ Hypoglycemia _____ Inhibition of the inflammatory response 16. (Page 8.) What are two of the major causes of Addison’s disease?
  23. 23. 17. (Page 8.) Is adrenal hyposecretion caused by a tumor of the anterior pituitary classified as a primary or secondary source for Addison’s disease? Veja a primeira parte deste arquivo sobre: Endocrine system review; Endocrine tissues: hormones and functions; Biochemistry, secretion, and transport of hormones

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