Anatomy of the Hypothalmus and Pituitary and the Adrenal Glands

Question 1

Where is the pituitary gland located?

Answer 1

hypophyseal fossa in sella turcica

Question 2

What gives birth to the adenohypophyseal (pars distalis/anterior pit.) structure?

Answer 2

Rathke’s pouch, from ectoderm, that is constricted and pinched off due to mesoderm growth.

Question 3

Another name for neurohypophyseal structure (posterior pituitary)?

Answer 3

Pars nervosa

Question 4

Describe the hormone release pathways in each pituitary structure

Answer 4

1. Anterior: hypothalamic neurons release releasing factors –> portal vessels –> activated endocrine cells in ant pit. –> secretion of hormones
2. Posterior: Hypothalamic secretory neurons secrete hormones directly on the vasculature in post. pit.

Question 5

Describe each of the hormones released and their effects from the posterior pituitary.

Answer 5

1. ANTIDIURETIC HORMONE (ADH, vasopressin):

Released in response to rise in electrolytes or fall in BP or blood volume

Decreases amount of water lost at kidneys

Causes constriction of peripheral blood vessels  increase in BP

2. OXYTOCIN:

Stimulates uterine smooth muscle contraction (parturition)

Stimulates contraction of myoepithelial cells (lactation)

Male – smooth muscle contractions in prostate gland

Question 6

What is the name of the surgery to remove cancer from pituitary?

Answer 6

Endonasal Trans-sphenoidal Surgery

Question 7

What type of germ layers form the adrenal gland?

Answer 7

A) Cortex –> mesoderm

B) Medulla –> neuroectodermal

Question 8

What are the layers that make up the adrenal cortex nd what hormones do each secrete?

Answer 8

Lateral to medial:
zona glomerulosa –> mineralocorticoids (aldosterone)
zona fasciculata –>Glucocorticoids (cortisone, hydrocortisone)
zona reticularis –> androgens and estrogens