Question

Which of the following could result in the increase in pH of blood leaving the stomachreferred to as alkaline tide? A)Increased secretion of somatostatin into the stomach

B)Increased production of carbonic acid in the parietal

C)Increased activity of CFTR channels of the pancreatic acini

D)Decreased activity of H+/K+ ATPase activity in the apical membrane of the parietal cells

Answer 1

the postprandial alkaline tide is the increased pH of blood which is leaving the stomach due to the excess secretion of gastric acid (HCl)

a- is wrong because increased secretion of somatostatin into the stomach will reduce HCl secretion by acting on parietal cells.

b- is correct because carbonic acid is needed for HCl production. An increased amount of carbonic acid means an increased amount of HCl production and bicarbonate removal. so the pH of blood leaving the stomach will be increased.

c- CFTR in the pancreas has no role is HCl secretion. so it is the wrong option.

d- H+/K+ ATPase is needed for the secretion of H+ ions into the stomach. when its activity is reduced, the production of HCl is reduced and the alkaline tide is reduced.