Gastric Secretion Flashcards
which three types of cells are found in gastric pits and what do they produce?
mucous neck cells - mucus
chief cells - pepsinogens
parietal cells - HCl + intrinsic factor
which enzyme catalyses the hydrolysis of carbon dioxide in the parietal cells?
carbonic anhydrase
why does the blood pH rise after eating a meal?
bicarbonate, a byproduct of acid production in the parietal cells, is released into the blood
which ion passes into the stomach lumen via ‘leaky channels’?
chloride
which compounds have an inhibitory effect on parietal cell HCl secretion?
prostaglandins
which nerve is stimulated by the sight, smell and taste of food?
vagus nerve
which gastric cell secretions are stimulated by acetylcholine?
parietal cells - HCl
ECL cells - histamine
which cells produce gastrin?
G cells
what does gastrin do?
stimulates parietal cell HCl secretion
which cells secrete histamine?
ECL cells
which compound stimulates the release of histamine from ECL cells?
gastrin/ACh
what happens when peptides are detected in the stomach?
G cells produce gastrin
what happens when acid is detected in the duodenum?
secretin is released and the enterogastric (splanchnic) reflex is triggered
how is pepsin inactivated?
neutral pH
which cells produce vitamin B12?
parietal cells
