Effect of glucose and inosine triphosphate on seasonal variation of gastric acid production in Rana pipiens

¹ Department of Physiology, University of Illinois, Urbana, Illinois

The production of acid in vitro by the gastric mucosa of 375 Rana pipiens was studied over a period of 13 months. The frogs were kept at 21°C and histamine was used to induce secretion. Four conditions were studied: a) control, no substrate added to the nutrient solution; b) 10 mm glucose added; c) 0.6 µm inosine triphosphate (ITP) added and d) 10 mm glucose and 0.6 µm ITP added. For each mucosa the change in hydrogen ion concentration (pH), titrable acidity and total chloride produced were measured. The results indicate that the seasonal variation in gastric acid production is due, in part, to a variation in the availability of substrate normally present.