Hypothalamus - Anterior Pituitary Axis Flashcards
What does sleep or exercise cause the release of?
GHRH (GH release hormone)
GHRH makes what hormone?
GH
GH goes to what target organs?
Liver + tissue (especially bone/cartilage)
What does GH make in the liver/bone/cartilage? What does the hormone do?
Insulin like growth factor IGF-1
Stimulates muscle, bone, + cartilage growth
What does temp. Below 97˚F (cold) cause the release of?
TRH (Thyrotropin releasing)
What hormone does TRH make
TSH
What is the target organ of TSH
Thyroid
What are the target hormones of the Thyroid?
T4 (Thyroxine) - inactive thyroid hormone
T3 (Triiodothyronine) - active thyroid hormone
What is the function of T4
Converted to T3 in liver by bile dependent deiodinase enzyme
What is the function of T3
Controls metabolism by making bigger + more mitochondria
What does chronic stress cause the release of?
CRH (Corticotrophin Releasing)
What hormone does CRH make
ACTH
What is the target organ of ACTH
Adrenal Cortex
Name the 3 steroid hormones of the adrenal cortex
Mineral corticoid aldosterone
Glucocorticoid cortisol
Androgens DHEA + Androstenodione
What is the function of Mineral Corticoid Aldosterone
Increase Na/K ATPase pump in late distal convoluted tubule and collecting duct of kidney
What is the function of Glucocorticoid Cortisol
Increases blood sugar level
What is the function of Androgens DHEA and Androstenodione?
Can be converted to testosterone, then estradiol
After puberty, what is released at different rates in males + females?
GnRH (Gonadotropin releasing)
When is GnRH released in females?
After puberty; first half of cycle
When is GnRH released in males?
After puberty; 8-14x per day
What hormones does GnRH make?
FSH, LH
What are the target organs of FSH
Ovary, Testes (seminiferous tubules)
What are the target organs of LH
Ovary, testes - cells of Leydig
What is the hormone of the Ovary in terms of FSH
Estradiol
