Immunohistochemical localization of Na+, K+-ATPase in human normal and malignant pancreatic tissues

Localization of Na+, K+-ATPase in the human pancreas was investigated immunohistochemically using rabbit antisera against Na+, K+-ATPase of the human kidney. The reaction product existed only on the luminal surfaces of both centroacinar and ductal cells in normal pancreatic tissue, whereas in chronic pancreatitis the localization of Na+, K+-ATPase was found frequently on the luminal surfaces of both centroacinar and ductal cells, and on the basolateral surfaces of some ductal cells. However, in acinar cells, the distribution of Na+,K+-ATPase was not detected in either the normal pancreas or chronic pancreatitis. In pancreatic carcinoma tissues, Na+,K+-ATPase existed very rarely in malignant cells. These results indicate that Na+,K+-ATPase is immunohistochemically localized on the membranes of centroacinar and ductal cells of the human pancreas, and that the antigenicity of Na+,K+-ATPase in pancreatic carcinoma cells differs from that in normal cells.