Gastrointestinal Secretions Flashcards
Source of Gastrin
G Cells of stomach, antrum, duodenum
Source of Somatostatin
D Cells of pancreatic islets and GI mucosa
Source of CCK
I Cells of duodenum and jejunum
Source of Secretin
S cells of duodenum
Source of GIP
K Cells of duodenum and jejunum
Source of Motilin
small intestine
Source of VIP
parasympathetic ganglia in sphincters, gallbladder, and small intestine
Source of Intrinsic Factor
parietal cells of stomach
Source of Gastric Acid
parietal cells of stomach
Source of Pepsin
chief cells of stomach
Source of Bicarbonate
mucosal cells of stomach and Brunner glands of duodenum
Stimulus and Action and Inhibition of Gastrin
Stimulus: protein, distention, vagus nerve (via GRP)
Action: stimulates gastric acid secretion, mucosal growth
Inhibition: acid and somatostatin
Stimulus and Action and Inhibition of Somatostatin
Stimulus: acid
Action: Inhibits release of all GI hormones. Inhibits Gastrin secretion – 2 pathways (direct & indirect)!!
Inhibition: Vagal stimulation
Stimulus and Action and Inhibition of CCK
Stimulus: small peptides, amino acids, fat
Action: Stimulates pancreatic enzyme secretion, pancreatic bicarb secretion, gallbladder contraction, growth of exocrine pancreas. Inhibits gastric emptying.
Inhibition: N/A?
Stimulus and Action and Inhibition of Secretin
Stimulus: Acid, fat, CCK
Action: Stimulates Pepsin secretion, pancreatic bicarb secretion, biliary bicarb secretion, growth of exocrine pancreas. Inhibits Gastric Acid secretion.
Inhibition: N/A?