Pituitary (Hypo-physis):

Origin: It develops from the ectoderm of embryo.

Position: It is a small, pea shaped gland attached to hypothalamus through (Infundibulum).

Hormones: It has 3 lobes:

Anterior, Intermediate and Posterior lobes.

1.Hormones from anterior lobe of pituitary:

FSH: Follicle stimulating hormone (In males, it stimulates sperm formation and in females it    stimulate the growth of follicles).

LH: Luteinizing hormone (In males, it stimulates the testis to produce androgens, and in females, it helps in the secretion of estrogen & progesterone).  

Somatotrophin: It helps in the growth of body. It is also called (GH) growth hormones.

Gonadotrophin: FSH and LH together referred to as gonadotrophic hormones.

Thyroid stimulating hormones: It stimulates the production of thyroid hormone from thyroid.

Adreno corticotrophic hormone: It helps the adrenal cortex to grow and to secrete 2 hormones (Glucocorticoid & mineralocorticoid).

Prolectin or luteotrophic hormone (PH/LTH): It helps in the production of milk after delivery.

 

2.Hormone from intermediate lobe of pituitary:

 It secretes a single hormone (MSH) Melanocyte secreting hormone which darkens the skin color in fishes, amphibians etc. It has no role in human body.

 

3.Hormones from the posterior lobe of pituitary:

 

Oxytocin: It is released at delivery and it induces Contraction of smooth muscles of uterus during delivery, it stimulates the release of milk. Oxytocin is also called birth hormone or Milk ejecting hormone.

Vasopressin: Also called (ADH) antidiuretic hormone. It contracts the arteries, increases the blood pressure in them. It also decreases the loss of water in urine by increasing re-absorption of water in DCT (distal convoluted tubule).

Disorders: Deficiency of ADH causes diabetes Insipidus.

 

If growth hormones are secreted improperly:

 

Dwarfism	Gigantism	Acromegaly
1.       It is caused due to the deficiency of growth hormones from early age.	1.       It is caused due to the excess of growth hormones from childhood.	1.       It is caused due to excess of growth hormones after adolescence.
2.       Here growth of body stops, making the patient dwarf.	2.       Here, body grows abnormally into a giant.	2.       Here, bones of lower jaw and limbs (arms, hand, lags) become abnormally large but body does not look giant.