Effect of cyproheptadine on gastric secretion in rats.

The effect of cyproheptadine on serum gastrin and glucose levels and intragastric pH values in male rats was studied. A significant increase in serum gastrin (p less than 0.001) and glucose levels (p less than 0.01) was observed after administration of 4 mg/kg, i.p. of cyproheptadine. Intragastric pH experimented a slight increase (p less than 0.05), and there were no significant changes in the gastrin levels 90 minutes after administration of different doses of cyproheptadine, although the intragastric pH values changes significantly (p less than 0.001) after administration of identical cyproheptadine doses. These results suggest that cyproheptadine stimulates gastrin secretion by an unknown mechanism and that this increase is not related to the alterations observed in serum glucose nor intragastric pH.