PHYS Flashcards
cephalic phase of secretion always work via the ___________________
vagus nerve
what are the fat soluble vitamins?
A
D
E
K
which cells secrete gastrin?
G cells of stomach
what is the stimulus for gastrin secretion?
small peptides & aa
distention of stomach
Vagus (via GRP)
what inhibits gastrin secretion?
inhibited by too much H+ in stomach
inhibited by somatostatin
what are the actions of gastrin?
increase gastric acid secretion
stimulates growth of the gastric mucosa
which cells secrete CCK?
I cells of duodenum & jejunum
what stimulates CCK secretions?
small peptides and amino acids
fatty acids
what are the actions of CCK?
stimulates contraction of gallbladder & relaxes sphincter of Oddi
- increase pancreatic enzyme & bicarb secretion
- increase growth of exocrine pancreas/gallbladder
- inhibits gastric emptying
which cells release secretin?
S cells of the duodenum
what stimulates the release of secretin by s cells?
H+ in duodenum
fatty acids in the duodenum
what are the actions of secretin?
increases pancreatic bicarb secretion
increases biliary bicarb secretion
decreases gastric acid secretion
what is the site of secretion for GIP?
duodenum & jejunum
what stimulates GIP secretion?
fatty acids, amino acids, and glucose
what are the actions of GIP ?
increases insulin secretion
decreases gastric acid secretion
the ductal cells in salivary glands reabsorb what 2 main ions?
sodium & chloride
the ductal cells in salivary glands secrete what 2 main ions?
K+ & bicarb
at low flow rates the pancreas secretes an isotonic fluid that is composed mainly of what two ions?
Na+ & Cl-
at high flow rates the pancreas secretes an isotonic fluid that is composed mainly of what two ions?
Na+ & bicarb
at low flow rates saliva is least like the initial secretion from the acinus it has the lowest concentration of what 2 ions and a high concentration of what other ion?
low concentration of Na+ & Cl- (which is reabsorbed)
high concentration of K+ (which is secreted)
at high flow rates saliva is most like the initial secretion from the acinus and has the highest concentration of what 2 ions and the lower concentration of what other ions?
higher concentrations of Na+ & Cl- (which is reabsorbed)
lower concentrations of K+ (which is secreted)
somatostatin is inhibited by stimulation of what nerve?
vagus
