AJP - Gastrointestinal and Liver Physiology, Vol 249, Issue 1 29-G33, Copyright © 1985 by American Physiological Society
Duodenal acidification releases cholecystokinin
Y. F. Chen, W. Y. Chey, T. M. Chang and K. Y. Lee
We studied the effect of hydrochloric acid (HCl) in the proximal small
intestine on release of cholecystokinin (CCK) and secretin and on exocrine
pancreatic secretion in conscious dogs with gastric cannulas and modified
Herrera pancreatic cannulas. Intraduodenal administration of HCl in a
concentration of 50 or 100 mM at rates of 0.05, 0.1, 0.2, and 0.4 mmol/min
significantly increased plasma concentration of CCK in a dose-dependent
manner, whereas plasma gastrin levels decreased. The increased plasma CCK
level paralleled a significant increase in pancreatic trypsin output.
Plasma secretin concentration and pancreatic bicarbonate output also
increased in response to the acid, and the increase was dependent on the
acid loads delivered in the duodenum. Thus, in dogs, HCl in the duodenum
releases both CCK and secretin to stimulate pancreatic secretion of
bicarbonate as well as enzymes.
