Oxytocin
Source of secretion:
It is mainly secreted by hypothalamus and stored in posterior pituitary gland. When the stimulus reaches the pituitary gland Oxytocin is released into the blood.
Chemistry:
It is the polypeptide having 9 amino acids.
Metabolic role:
- In females :
- Effect on mammary glands:
- Causes ejection of milk from the mammary glands by causing the contraction of the myoepithelial cells. (Milk ejection reflex).
- Effect on uterus:
- Causes of contraction of uterus and helps in expulsion of fetus during pregnancy.
- In non pregnancy it facilitates the transport of sperms upto the fallopian tube.
- In males:
- Facilitates the release of sperms into urethra by causing contraction of smooth muscle fibers in reproductive tract.