The document discusses prolactin, a hormone produced by the pituitary gland. It describes the factors that regulate prolactin secretion, such as estrogen and dopamine. The main functions of prolactin include stimulating breast development and lactation. The document also covers disorders of low or high prolactin, and their potential causes and symptoms. Diagnosis involves medical history, exams, and blood tests to measure prolactin and other hormone levels. Treatment depends on the underlying cause but may include dopamine agonists or surgery for pituitary tumors.
introduction
pituitary gland hormone
factor affecting secretion
function
regulation of secretion of prolactin
causes and symptoms of hypoprolactinaemia
causes and symptoms of hyperprolactinaemia
diagnosis
treatment
mechanism of prolactin
role of prolactin
uses
introduction
pituitary gland hormone
factor affecting secretion
function
regulation of secretion of prolactin
causes and symptoms of hypoprolactinaemia
causes and symptoms of hyperprolactinaemia
diagnosis
treatment
mechanism of prolactin
role of prolactin
uses
Thyroid hormone,
structure of hormone,
synthesis of thyroid hormone,
mechanism of Thyroid hormone action,
Physiological effect of Hormone,
Disorders related with thyroid hormone,
drugs used in treatment for the thyroid disorders.
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Steroid hormones can be grouped into 2 classes, corticosteroids (typically made in the adrenal cortex, hence cortico-) and sex steroids (typically made in the gonads or placenta).
Thyroid hormone,
structure of hormone,
synthesis of thyroid hormone,
mechanism of Thyroid hormone action,
Physiological effect of Hormone,
Disorders related with thyroid hormone,
drugs used in treatment for the thyroid disorders.
One test can save your life. Know what a Follicle Stimulating Hormone(FSH) is, why you should have it, who should get it, and where can you get tested as well as get your results fast. If you want to read more about Follicle Stimulating Hormone(FSH), click the link below.
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Steroid hormones can be grouped into 2 classes, corticosteroids (typically made in the adrenal cortex, hence cortico-) and sex steroids (typically made in the gonads or placenta).
Presentation for Progesterone Amp. 100 mg/ml and Progesterone pessaries 400mg for treatment of PTB, Recurrent miscarriage, Threatened abortion, Post-natal psychosis.
3. IntroductionIntroduction
Human PRL is a single-chain polypeptide of
199 amino acids. It has a molecular weight of
23 kDa.
Prolactin is synthesized in and secreted from
specialized cells of the anterior pituitary
gland, the lactotroph cells.
The pituitary gland (also called the master
gland) is an endocrine gland about the size of
a pea (weighing 0.5 g) and located at the base
of the brain (just below the hypothalamus).
The pituiary gland has two parts – the anterior
lobe and posterior lobe – that have two
seperate functions.
The pituitary gland secrets hormones
regulating homeostasis, including tropic
hormones that stimulate other endocrine
glands.
6. FunctionFunction
o
PRL is responsible of:
Primarily; initiating and sustaining lactation and stimulation of breast development along with
Estrogen during pregnancy.
o
Other functions of PRL:
Reproductive; inhibition of ovulation by decreasing secretion of LH and FSH during pregnancy.
Regulation of immune system;by stimulating T cell functions.
Osmoregulation; transporting fluid, Na, Cl and Ca across epithelial intestinal membrane and
promoting Na, K and water retention in the kidney.
Metabolism; essential in fat cell production, differentiation and regulation.
7. Regulation of secretion
o Breast feeding is the major stimulus of prolactin production.
o Triggered by the prolactin releasing hormone (PRH)
o Inhibited by prolactin inhibiting hormone (PIH), dopamine,
acting on the D2 receptors present on the lactotroph cells
In males, the influence of PIH predominates.
In females, PRL levels increase and decrease in accordance with
estrogen blood levels;
-Low estrogen levels stimulate PIH release.
-High estrogen levels promote release of PRH and thus PRL.
o Blood levels increase towards the end of the pregnancy.
o When the mother no longer needs to produce milk, dopamine
inhibits prolactin by signaling the hypothalamus to stop.
8. Causes and Symptoms of HypoprolactinaemiaCauses and Symptoms of Hypoprolactinaemia
Decreased PRL hormone secretion by the anterior pituitary gland
Common causes of Hypoprolactinaemia:
o Sheehan'ssyndrome (caused by ischaemic necrosis of the pituitary gland due to blood loss during or after child
birth)
o Hypopituitarism
o Excess dopamine
o Autoimmune disease
o Growth hormone deficiency
o Head injury
o Infection (e.g. Tuberculosis)
Symptoms:
o Ovarian diseases, delayed puberty and infertility.
o Impotence and abnormal spermatogenesis.
9. Causes and symptoms of HyperprolactinaemiaCauses and symptoms of Hyperprolactinaemia
Increased PRL hormone secretion by the anterior
piruitary gland
Common causes of Hyperprolactinaemia
Stress
Medications e.g. Antipsychotic drugs
Primary hypothyroidim: PRL is stimulated by
the increase of TRH.
Pituitary gland tumours
Prolactinoma: a non-cancerous tumour of the
pituitary cell secreting PRL.
Idiopathic hypersecretion: e.g. due to impaired
secretion of dopamine
Other: chest wall lesions and chronic renal
failure.
Symptoms:
Women:
Oligomenorrhoea
Amenorrhoea
Galactorrhoea
Infertility
Hirsutim
Osteoporosis
Men (late onset):
Gynaecomastia.
Impotence.
Osteoporosis
In both sexes, tumour mass effects may cause visual-
field defects and headache.
10. Diagnosis and TreatmentDiagnosis and Treatment
Diagnosis:
o
History (medications, oligomenorrhoea,
hirsutim)
o
Physical examination ( galactorrhoea)
Laboratory
Pregnancy Test
Prolactin
Macroprolactin (inactive, large complex of
serum prolactin with an IgG antibody)
TSH, Free T4
U&Es
Tes, LH, and FSH
o
MRI scan ( prolactinaemia)
o
Visual field tests (optic nerve)
Treatment:
o
Hyper prolactinaemia: dopamine agonists
(e.g. Bromocriptine or Cabergoline)
o
Surgery removal and/or radiation therapy
(large pituitary tumours)
o
Tyroid abnormalities: thyroid hormone
replacement ( e.g. levothyroxine)
o
Ovarian insufficiency: hormonal therapy
(e.g. Estrogens and Progestins)
11. Case studyCase study
A 56 years old male who was recently admitted to A&E for fall-related injuries (cracked
right sided rib and right knee injury)
In June, the pt was referred to the endocrine clinic due to the detection of an adrenal incidentaloma.
Other clinical history include atrial fibrillation and pleural thickening.
Lab investigations (12/09/2016)
? cause
Test Reference
range
Result
Prolactin 73-407 mU/L >42000
Tes Male >50 yrs
7-30 nmol/L
3.0
TSH 0.35-5.0 mU/L 4.64
FT4 9-19 pmol/L 12
LH 2-10 IU/L 2.0
FSH 1-5 IU/L 3.0
12. ProlactinomaProlactinoma
MRI scan was performed to confirm or rule out prolactinoma.
The radiology report:
”46 x 37 x 35 mm pituitary tumour in keeping with pituitary macroadenoma.
Encroachment of clivus, sphenoid sinus, left-sided optic pathways and
cavernous sinus bilaterally.”
13. References
Freeman M. et al(2000) Prolactin:Structure, Function, and Regulation of Secretion, American Physiological Society [online]
http://physrev.physiology.org/content/80/4/1523.long
Ugwa E. et al (2016) Assessment of serum prolactin levels in among infertile women with galactorrhea attending a
gyneclogical clinic North-West Nigeria, Nigerian Medical Journal, [online]
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4924401/
Nevels R. et al (2016) Paroxetine- The Antidepressant from Hell? Probably Not, But Caution Required, Psychopharmacology
Bulletin, [online] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5044489/
Nessar A. (2010) Clinical Biochemistry. New York. Oxford University Press.
Besser G.and Thorner M. (1994) Clinal Endocrinology. London. Times Mirror International.
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