HPG and Steroids Flashcards
repro problems can occur on what 3 levels?
hypothalamic
pituitary
gonadal
what 2 major hormones are released from the pituitary?
oxytocin
ADH
what does GnRH do?
binds to receptors on the anterior pituitary to have LH and FSH released
where does gnrh come from?
the hypothalamus
which 2 pituitary signals help secrete FSH?
inhibins
activans
what does follistatin do?
inhibits FSH release
what is the end result of stress in the “circhoral oscillator”?
stress causes gnrh to no longer be released in pulses, so FSH and LH are not released normally
what do gnrh agonists do?
release gnrh chronically, so cause decreased gonadal steroids (“chemical castration”)
what do gnrh antagonists do?
cause an immediate decrease in fsh/lh
what are the 3 classes of gonadal hormones
progestins
andorgens
estrogens
how are gonadal steroids synthesizdd?
a) from acetate
b) from cholesterol
what is the precursor to all steroids?
pregnenolone
what 2 parts of the body are known for making steroids?
gonads
adrenal cortex
what enzyme must be present for steroids to be made?
cytochrome p450
if there is a steroid imbalance, what in general could be going on?
a) primary steroid synthesis problem
b) change in conversion from 1 steroid to another
