Neurohormones

Question 1

What hypothalamic neurohormones are released to control the anterior pituitary?

Answer 1

CRH - ACTH

TRH - TSH

GnRH - FSH & LH

GHRH - GH, gastrin, VIP, glucagon, insulin, prolactin

Somatostatin (GH inhibiting H) - inhibits

Dopamine - inhibits prolactin

Question 2

Describe the HPT axis

Answer 2

TRH from hypothalamus - anterior pituitary to release TSH

TSH acts on thyroid to increase T4/T3 secretion

T3 is the potent TH, targets deiodinase enzyme (DI) to convert T4 to T3

Pituitary expresses deiodinase for -ve feedback

increased metabolic rate
HR
anxiety

Question 3

what hypothalamic neurohormones are released to control the posterior pituitary?

Answer 3

Vasopressin - ADH for osmoregulation
Oxytocin - lactation, mating, smooth muscle contraction of of repro - reward via amygdala

Question 4

What is the GH receptor mechanism?

Answer 4

binding of GH = recruitment and autophosphorylation of tyrosine AA leading to recruitement of JAK which phosphorylate protein STAT