prolactin and growth hormone Flashcards
(21 cards)
why is the anterior and posterior pituitary important for lactation
posterior: release oxytocin stim. milk ejection
anterior: release prolactin which stim milk production
how is prolactin made
made and secreted by lactotrophs in the anterior pituitary gland
function of prolactiin
pregnancy and lactation
uterine smooth muscle contraction
reproduction
prolactin regulation cascade
suckling stim hypo
TRH release stim pituitary gland to release prolactin to the mammary gland
the release of prolactin is a neg feed back loop producing dopamine which will inhibit the hypo
physiological causes of hyperprolactinemia
pregnanacy
breast feeding
stress
excercise
sleep
other causes of hyperprolactinemia
pituitary tumoe
dama to hypothalamic pituitary dopamin path
medication
renal failure
liver disease
primary hyperthyroidism
macroprolactin
clinical presentation of hyperprolactinemia
galactorrhea
hypogonadism
low sex drive
headache and visual problems
female clinical presentation
menstrual dysfunction
vaginal dryness
males clinical presentation
erectile dysfuction
decrease body hair and muscle mass
delayed puberty
how is hyperprolactinemia diagnosed
increased prolactin concentration in the serum: immunoassay
MRI tumors
gel filtration chromatogrpahy
polyethylene glycol precipitation
obtain result from more than one immunoassay
growth hormone
mediated trhoguh growth hormone receptors on many tissues
indirect action through hepativ insulin growth factor release
growth hormone functions
tissue and bone growth
response to stress
modulates fat/carb/protein metabolism and body composition
raises glucose and FFA concentration
when is growth hormone released the most
at night
GH influenced by
age sex body composition
GH is measured
immunoassay
would have to do suppresion testinf
growth hormone regulation cascade
stimulant on hypo release GHRH to pituitary which will release GH to target tissue. target tissue will release IGF-1 which will inhibit the pituitary and release somatostatin which will inhibit the hypothalamus
what are some GH stimulants
excercise
stress
sleep
fasting
amino acids
hormones
insulin like growth factor
mediates indirect growth and fat metabolism effects of GH
has a steady concentration and measured with chemiluminescence immunoassay
GH excess
pituitary tumors
hypothalamic lesions
GHRH producing tumors
result: soft tissue and bone overgrowth
GH excess lab measurement
measure serum IGF-1
glucose supression test
MRI
