Anterior Pituitary

Question 1

hypothalamic nuclei of anterior pituitary

Answer 1

• PVN
• anterior hypothalamus
• median preoptic nucleus (MPO)
• arcuate nucleus (Arc)

Question 2

parvicellular neurons

Answer 2

• originate in hypothalamic anterior pituitary nuclei

- send axons to and terminate at median eminence

Question 3

parvicellular neurons synthesize….

Answer 3

hypothalamic releasing hormones (XRH)

hypothalamic release-inhibiting hormones (XIH)

Question 4

median eminence

Answer 4

secrete hypothalamic release & release-inhibiting hormones from parvicellular nerve terminals into blood

Question 5

Hypothalamic Nuclei of TRH

Answer 5

PVN

Arcuate Nucleus

Question 6

Hypothalamic Nuclei of GnRH

Answer 6

Anterior and Medial Hypothalamus

Medial Preoptic Nucleus (MPO)

Question 7

Hypothalamic Nuclei of GHRH

Answer 7

arcuate nucleus

Question 8

Hypothalamic Nuclei of Somatostatin (GHIH)

Answer 8

PVN

Question 9

Hypothalamic Nuclei of Dopamine (Prolactin-inhibiting Hormone)

Answer 9

Arcuate nucleus

Question 10

5 endocrine cell types of the pars distalis of anterior pituitary

Answer 10

1. corticotrophes
2. thyrotrophes
3. gonadotrophes
4. somatotrophes
5. lactotrophes

Question 11

Acidophilic Trophes

Answer 11

• somatotrophes

- lactotrophes

Question 12

Basophilic Trophes

Answer 12

• corticotrophes
• thyrotrophes
• gonadotrophes

Question 13

Lactotrophes

Answer 13

15-20% of total

Prolactin

Question 14

Corticotrophes

Answer 14

10% of total

ACTH

Question 15

Thyrotrophes

Answer 15

5% of total

TSH

Question 16

Gonadotrophes

Answer 16

5-10% of total

FSH & LH

Question 17

Somatotrophes

Answer 17

60% of total

Growth Hormone

Question 18

Glycoprotein Tropic Hormones

Answer 18

TSH

FSH

LH

Question 19

Proopiomelaniocortin (POMC)-derived hormone

Answer 19

ACTH

Question 20

POMC

Answer 20

prohormone made by the corticotrophins in anterior pituitary

Question 21

Crossover between Anterior and Posterior Pituitary

Answer 21

• normal conditions = secretion of ACTH regulated by CRH
• stress conditions = secretion of ACTH amplified by a mechanism that involves stimulation of anterior pituitary corticotrophes by ADH
• certain parvicellular neurons in PVN make ADH
• —-> these neurons terminate at median eminence
• during stress: these neurons secrete ADH at median eminence
• —> ADH taken via portal circulation to the anterior pituitary corticotrophes where it stimulates ACTH secretion