Abstract
Cyproheptadine causes a reversible depletion of extractable immunoreactive insulin in the pancreas of rats given the drug orally. This communication describes the use of the unlabeled antibody enzyme method to demonstrate cyproheptadine-induced insulin depletion by light and electron microscopy. The results confirm that insulin is lost from rat pancreatic beta cells as treatment commences and returns upon cessation of treatment. The small amount of insulin which remains in beta cells of cyproheptadine-treated rats is apparently associated with normal appearing insulin secretory granules. It is not present in substantial amounts elsewhere in the cytoplasm.
Key words
Cyproheptadine - Insulin Localization - Electron Microscopy - Immunocytochemistry - Pancreatic Beta Cells
1 Supported by USPHS Grant GM 12675.
2 Present address: Department of Pharmacology, Michigan State University, East Lansing, Michigan 48824, USA.
3 Present address: Department of Anatomy, University of Minnesota, Minneapolis, Minnesota 55455, USA.
