Cholecystokinin intracerebroventricularly applied stimulates gastric acid secretion.

Intracerebroventricularly applied cholecystokinin-8-sulfate (CCK-8) induced a significant and dose-related increase in gastric acid output in urethane anesthetized rats. On the other hand, cholecystokinin-8-non-sulfate (CCK-8-NS), a non-active analogue of CCK-8, and pentagastrin as one of the cholecystokinin families, had no effect on gastric acid secretion. Pretreatment with atropine 5 min prior to CCK-8 as well as subdiaphragmatic vagotomy completely blocked this peptide-induced increase in gastric acid secretion. These results suggest that centrally applied CCK-8 induced a vagally mediated increase in gastric acid secretion.