Hormones of posterior pituitary glands-Oxytocin & ADH

1. Ms.Anu Sebastian: B.Pharm; M.Pharm
Assistant Professor,
Dept. Of Pharmacology
Nirmala College Of Pharmacy
Muvattupuzha,Ernakulam,Kerala

2. POSTERIOR PITUITARY GLAND
 Posterior pituitary gland do not synthesize any hormone. But it
stores & release two hormones of hypothalamus.
 Oxytocin and vasopressin/ADH
 These hormones are synthesized in the neuronal cell bodies in
hypothalamus.
 Oxytocin is synthesized on Paraventricular neuronal cell body.
 ADH is synthesized in Supraoptic neuronal cell body.

3.  After the synthesis , these hormones are packed into secretory
vesicles.
 These secretory vesicles are transported through the neuronal
axons(Neuronal axons are present in posterior pituitary gland).
 By exocytosis the hormones are released into posterior
pituitary.

5. OXYTOCIN
 This hormone is having two functions:
During delivery it enhances the contraction of uterine
smooth muscles.
After delivery it stimulates the mammary glands for milk
production.

6. ADH/ANTIDIURETUC HORMONE/VASOPRESSIN
 This hormone by increasing the water reabsorption in Kidney,
decreases the urine output.
ADH FUNCTIONS
 Kidneys- increases water reabsorption- decreases urine output
 Sweat gland- decreases sweating- decreases water loss
 Contraction of arterioles –increases blood pressure

7. REGULATION OFADH SECRETION
High osmotic pressure(Due to dehydration/decreased blood pressure)
Stimulate osmoreceptors
Stimulate Supraoptic neuronal cell bodies of hypothalamus
Stimulate synthesis of ADH
ADH is released from posterior pituitary
ADH reaches kidney through circulation
Decreases urine formation & increases water volume of blood
Dcreases osmotic pressure

8. THANK YOU