Histochemical mapping of alkaline phosphatase in the digestive system of a few teleost fishes

Abstract

The alkaline phosphatase activity is mapped in all the parts of the digestive system of Colisa fasciatus, Macrognathus aculeatus, Notopterus notopterus and Nandus nandus. In the posterior region of the alimentary canal of all the 4 fishes the activity is poorer as compared to other parts. In Colisa fasciatus and Macrognathus aculeatus, the activity at the distal end of pyloric caeca is poorer as compared to the proximal part. In Notopterus notopterus and Nandus nandus however, it is practically of the same intensity at both the parts. Mucosal and submucosal layers have been found to have intense alkaline phosphatase activity as compared to muscularis and serosal layers. Except Nandus nandus, gastric glands of all the remaining fishes show partial activity of this enzyme. However, gastric epithelium of all the four fishes shows good activity. Hepatic cells are rich in alkaline phosphatase activity. The cytoplasm of the hepatic cells and pancreatic acinar cells have intense reaction. Presence of alkaline phosphatase is in relation with the secretory and absorption activity of tissue or cells.