Immunocytochemical identification of cells containing insulin, glucagon, somatostatin, and pancreatic polypetide in the islets of langerhans of the guinea pig pancreas with light and electron microscopy

Cell types containing insulin, glucagon, somatostatin, and pancreatic polypeptide were identified in guinea pig islets with light and electron microscopic immunoperoxidase staining. Cells containing immunostainable insulin (B cells) are located throughout the islets, including the islet periphery, and contain irregularly shaped granules (350-550 nm). Granule contents are of variable opacity and ar…