Flashcards in SR 34 - GI Hormones and Physiology Deck (39)
What do these cells produce? Gastric parietal cells
What do these cells produce? Chief cells
What do these cells produce? G cells
Found in the antrum
What do these cells produce? Mucous neck cells
Name the receptors on the parietal cell that stimulates hCl release
Where is most of hte bile acids absorbed?
Where is intrinsic factor + B12 absorbed?
How may times is the entire bile acid pool circulated during a typical meal?
What are timulators of gallbladder emptying?
What are the inhibitors of gallbladder emptying?
Sympathteitcs (you cannot flee and ingest food at the same time)
What stimulates the release of CCK?
Fat, protein, amino acids, HCl, antral stretch
What inhibits the release of CCK?
What are CCKs actions?
Opens ampulla of vater
Slows gastric emptying
Stimulates pancreatic acinar cell growth and release of exocrine products
What is the source of CCK?
Duodenal mucosal cells
What is the source of secretin?
Duodenal cells (argyrophilic S cells)
What stimulates secretin release?
What inhibits release of secretin?
High pH in the duodenum
What are the actions of secretin?
Release pancreatic bicarb/enzymes/H2O
Decreases lower esophageal sphincter tone
Decrease release of gastric acid
What is the source of gastrin?
Gastric antrum G-cells
What stimulates gastrin release?
Stomach peptides/amino acids
What inhibits gastrin release?
What are the actions of gastrin?
Release of HCl from parietal cells
Trophic effect on mucosa of the stomach and small intestine
What is the source of somatostatin?
Pancreatic D cells
What stimulates the release of somatostatin?
What are the actions of somatostatin?
Globally inhibits GI function
What is the purpose of hte colon?
Reabsoprtion of H2O and storage of stool
What is the main small bowel nutritional source?
What is the main nutritional souce of the colon?
Butyrate (short-chain fatty acid)
Where is calcium absorbed?
Where is iron absorbed?
What hormone primarily controls gallbladder contraction?
What are hte main constituents of bile?
Water, phospholipids, bile acids, cholesterol, bilirubin
How do opiates affect the bowel?
They stimulate sodium absoprtion and inhibit secretion in the ileum as well as decreasing GI motility by incoordinated peristalsis
Which electrolytes does the colon actively absorb?
Which electrolyte does the colon actively secrete?
HCO3 (which is why diarrhea causes normal anion gap acidosis)
Which electrolyte does the colon passively secrete?
What is hte gastrocolic reflex?
Increased secretory and motor functions of the stomach result n increased colonic motility
What is the blood supply to the liver?
75% from portal vein (products of digestion)
25% from hepatic artery (rich in O2)