Hormones and Paracrine Mediators of the GI Tract Flashcards
What cells secrete gastrin? Where are those cells located?
G-cells in the antrum of the stomach.
What is the stimuli for gastrin secretion?
small peptides and amino acids
What is the action of gastrin?
Stimulates parietal cells –> increased H+ secretion
Stimulates ECL cells –> histamine secretion
Stimulates growth of gastric mucosa
What cells secrete CCK? Where are those cells located?
I-cells of the duodenum
What is the stimuli for CCK secretion?
Fatty acids, hydrolyzed protein
What is the action of CCK?
Decreases gastric emptying and H+ secretion
Decreases food intake
Increases Pancreatic enzyme secretion
Increases contraction of the gallbladder
What cells secrete secretin?
S cells of the duodenum
What is the stimulus for secretion of secretin
H+ in the duodenum
What is the action of secretin?
Increased pancreatic ductal secretion (H2O and HCO3-)
What cells secrete GIP (glucoinsulintropic peptide)
K cells of the duodenum and jejunum
What is the stimuli for secretion of GIP?
Fatty acids and glucose
What is the action of GIP?
Increase insulin secretion from pancreas (Beta cells)
What cells secrete peptide YY?
L cells of the intestine
What is the stimulus for peptide YY secretion?
fatty acids, glucose, hydrolyzed protein
What is the action of peptide YY?
Decreased gastric emptying and acid secretion, decreased pancreatic secretion, decreased intestinal motility, decreased food intake
