GI hormones Flashcards
where is gastrin produced
G cells in the antrum, duodenum and jejunum
what is the target of gastrin
parietal cells in the body of the stomach
what is the function of gastrin
increases H+ secretion
mucosal growth
where is cholecystokinin produced
I cells in duodenum and jejunem, neurones in the iluem and colon
what is the target of cholecystokinin
pancreas, gall bladder
what is the function of cholecystokinin
increases enzyme secretion
increases contraction of gallbladder
(increases bicarbonate secretion
increases growth of pancreas
inhibits gastric emptying)
where is secretin produced
S cells in small intestine
what is the function of secretin
increases bicarbonate ion and fluid secretion by pancreas
decreases gastric acid secretion
(increases pepsin secretion
increases growth of pancreas)
where does secretin act
stomach and pancreas
where is gastric- inhibitory peptide produced
K cells in duodenum and jejunum
where does GIP act
pancreas and stomach
what is the function of GIP
decreases fluid absorption
increases insulin release
decreases gastrin release
where is glucagon produced
alpha cells islets of langerhans
what is the target of glucagon
liver
what is the function of glucagon
increases glycogenolysis and gluconeogenesis
what is the function of Guanylin
increases fluid adsorption
where is guanylin produced
endocrine cells in upper GI tract
where does guanylin act
intestine
where does motilin act
oesophageal sphincter, stomach, duodenum
where is motilin produced
M cells in the duodenum and jejunum
what does Motilin do
increases smooth muscle contraction- gastric motility and intestinal motility
where is neurotensin produced
N cells of ileum
where does neurotensin act
smooth muscles and vagus
what does neurotensin do
relaxes smooth muscle
decreases gastric acid secretion
what does somatostain do? (paracrine)
decreases gastrin release
increases fluid absorption
decreases fluid secretion
increases smooth muscle contraction
decreases endo and exocrine secretions
decrease bile flow
where is somatostatin produced
D cells of stomach and duodenum
delta cells of pancreatic islets
what is the target for somatostatin
stomach
intestine
pancreas
liver
what is the function of histamine ( paracrine)
stimulates H+ secretion from parietal cells in the stomach
what is the function of aCh
contraction of GI wall
relaxation of sphincters
increases secretion
what stimulates gastrin secretion
protein
distension
nerves
acid inhibits release
what stimulates cholecystokinin production
protein
fat
acid
what stimulates secretin
acid
fat
what stimulates gastric inhibitory protein
protein
fat
carbs
what do enterochromaffin cells produce
serotonin
what are the types of enteroendocrine cells
K- gastrin inhibitory peptide L- glucagon like peptide I -cholecystokinin G- gastrin enterochromaffin- serotonin N- neutotensin S - secretin
ghrelin
hunger and appetite
epidermal growth factor
mucosal protection
what cells produce bile
hepatocytes
what is the mechanism of alcholic fatty liver disease
energy is diverted to breaking down alcohol and not fat
