Gastric motility Flashcards
what are the steps of gastric filling / storage? what do they have in common?
- receptive relaxation and gastric accommodation 2. rise in gastric volume with no change in pressure
what are the stimuli for the receptive relaxation phase of gastric filling?
vagovagal reflex, swallowing, NO
what are the stimuli for the gastric accommodation phase of gastric filling?
gastric filling, ENS, modulated by vagus nerve
what cells initiates propulsion during gastric churning?
pacemaker cells near greater curvature
what factors dictate the rate of gastric emptying?
- content of digested material (fat / protein) 2. hormones (secretin, CCK, gastrin)3. NTs (Ach, NO, 5-HT, VIP)
what mediates impaired gastric emptying in response to HCl in the duodenum?
secretin
what mediates impaired gastric emptying in response to fat in the duodenum?
CCK
what mediates impaired gastric emptying in response to protein in the stomach?
gastrin
what mediates impaired gastric emptying in response to duodenal distension?
ENS
what mediates impaired gastric emptying in response to vagal stimulation?
Ach, opioid, 5-HT, NO, VIP
what are the effects of CCK on the gall bladder?
contraction
what are the effects of CCK on the pancreas?
acinar secretion
what are the effects of CCK on the stomach?
reduced emptying
what are the effects of CCK on the sphincter of Oddi?
relaxation
what are the two primary CNS loci mediating emesis?
chemoreceptor trigger zone, emetic center
