Localization of Three Types of the Inositol 1,4,5-Trisphosphate Receptor/Ca2+ Channel in the Secretory Granules and Coupling with the Ca2+ Storage Proteins Chromogranins A and B.

Abstract

Localization of Three Types of the Inositol 1,4,5-Trisphosphate Receptor/Ca2+ Channel in the Secretory Granules and Coupling with the Ca2+ Storage Proteins Chromogranins A and B. Although the role of secretory granules as the inositol 1,4,5-triphosphate (IP3)-sensitive intracellular Ca2+ store and the presence of the IP3 receptor (IP3R)/Ca2+ channel on hte secretory granule is not known. We have there fore investigated the presence of different types of IP3R in the SG.