Ultrastructural and immunohistochemical demonstration of pancreatic polypeptide-containing F-cells in the stomach and pancreas of Tupaia belangeri.

The gastro-entero-pancreatic (GEP) system in Tupaia belangeri contains a specific cell which reacts with antisera to pancreatic polypeptide (PP). The cells are scattered between exocrine pancreatic cells and also found in the pancreatic islets. Furthermore, they are also located in the fundic glands and to a very small extent in the corpus mucosa and in the glands of the upper duodenum. The cell reacting with antisera against PP is identified as the F-cell which has a specific ultrastructure especially with respect to its secretion. The present identification of the F-cell as the PP-cell in pancreas and stomach is discussed with respect to its possible functional implications.