Last Modified:  January, 2007 (J. Crimando).

Endocrine Tissues:
Pituitary Gland

Pituitary Gland image
The pituitary gland (also known as the hypophysis) is situated in the sella turcica immediately inferior to the hypothalamus and adjacent to the optic chiasm at the base of the brain. It has two portions derived from different tissues:
The Adenohypophysis (anterior pituitary) is glandular tissue derived from the oral mucosa epithelial tissue.
The neurohypophysis (posterior pituitary) is neuronal tissue derived from neurons originating from hypothalamic nuclei.
The infundibulum connects the hypothalamus to the pituitary and serves as a vital communication pathway for the hypothalamus to regulate pituitary function.

Pituitary gland 25X Pituitary gland 100X Anterior Pituitary 100X Posterior Pituitary Pituitary Tutorial


POSTERIOR PITUITARY
Hormone Secreted Main Functions
Oxytocin   stimulates uterine contraction (labor contractions)
  stimulates milk let-down reflex
Antidiuretic hormone   stimulates water retention by renal collecting ducts in kidneys
  inhibits sweat glands in skin
  stimulates vasoconstriction in skin (hence name "vasopressin")


ANTERIOR PITUITARY
Hormone Secreted Main Functions
Growth hormone   growth of skeletal muscle, bone, cartilage
  increase protein synthesis
  stimulates lipolysis for ATP production
  reduces glucose use for ATP production
  increase release of stored glucose from liver
  raises blood glucose level (diabetogenic effect)
Thyroid-stimulating hormone   triggers thyroid hormone release from thyroid
  indirectly enhances basal metabolism of cells via thyroid activation
Adrenocorticotropin hormone   stimulates glucocorticoid (cortisol) secretion from adrenal cortex
  indirectly enhances "stress-response" via adrenal activation
Prolactin   promotes milk production by mammary glands
Follicle-stimulating hormone   induces spermatogenesis in testes of males after onset of puberty
  induces 2o oocyte development in ovaries of females after onset of puberty
  stimulates growth of ovarian follicles (granulosa cells)
  stimulates estrogen production from ovaries
Luteinizing hormone   enhances 2o oocyte maturation in ovaries
  induces ovulation
  maintains corpus luteum for first two weeks after ovulation
  stimulates testosterone production from testes