Islet amyloid polypeptide (IAPP) is synthesized in the islets of Langerhans. Detection of IAPP polypeptide and IAPP mRNA by combined in situ hybridization and immunohistochemistry in rat pancreas.

We investigated the localization of IAPP mRNA by means of in situ hybridization in tissue sections of rat pancreas. A 35S-labeled, IAPP-specific DNA probe--hybridized specifically in the islets of Langerhans. This localization was confirmed by immunohistochemical localization of insulin and IAPP polypeptides on adjacent tissue sections. Moreover, combined in situ hybridization of IAPP mRNA and immunohistochemistry of insulin and IAPP polypeptide on the same section, using insulin as specific marker shows the presence of IAPP mRNA in the islets of Langerhans.