lab med Flashcards
about 80% of insulin uptake is independent of insulin what/where are these insulin independent cells
nerve tissue- brain; RBC, mucosal cells of the GI tract, and exercising skel m.
in a fasting state as insulin lvls dec where/how is energy produced
glycogen is broken down by the liver (glycogenolysis) and fatty acids are converted to ketone bodies (lipolysis)
at what glucose cx is a pt considered hypoglycemic
<70mg/dL
what happens in the event of hypoglycemia
alpha cells in the pancreas release glucagon which stimulates (gluconeogenisis) and glycogenolysis. glucagon also facilitates(lypoysis)
in addition to glucagon secretion, hypoglycemia leads to the secretion of what counterregulatory hormones
GH, epinephrine, and cortisol
what does epinephrine do
along with glucagon it promotes glycogenolysis and gluconeogenisis
what does cortisol do
cortisol increases glucose lvls by stimulating gluconeogenisis
what does growth hormone do
inhibits the uptake of glucose by tissues when hypoglycemic
what does amylin do
delays gastric emptying - slows intestinal carbohydrate absorption resulting in lower postprandial glucose lvls; also suppresses hepatic glucose output by inhibiting glucagon after a meal; satiety
what is the incretin effect
postprandial Beta cell glucose responses is greater when glucose is given orally than IV
what are examples of incretin hormones
GLP-1 and GIP- stimulate insulin release when glucose lvls are elevated
under normal circumstances how does DDP-4 effect incretins
it rapidly degrades them into inactive forms after their release into the circulation- 1/2 life <5min
T/F GLP-1 but not GIP also suppress glucagon production in pancreatic alpha cells when glucose is elevated
True
how does the kidney contribute to glucose homeostasis
by reabsorbing all of the glucose in the proximal tubule and returning it to the circulation
what specific glucose transport proteins mediates glucose resorption by the kidneys
the sodium glucose cotransporters
SGLT
