Histochemical localization of hydrochloric acid in the stomach of two teleost fishes.

The localization of hydrochloric acid in the gastric glands of Ophycephalus punctatus and Heteropneustes fossilis has been examined histochemically. The fishes were force-fed with the Prussian blue reagents in a test meal and the distribution of the precipitate was examined at regular intervals. Maximum amount of precipitate was observed in the lumen and at the mouth of the openings of the gastric glands 12 h after feeding in Ophiocephalus and at 18 h in Heteropneustes. Pepsinogen granules were distributed in all the cells lining the gastric glands. No histochemical difference was observed in the cells lining the gastric glands, and all the cells were capable of producing both HC1 and pepsinogen.