CORTICOTROPIN-RELEASING HORMONE AND CALCIUM SIGNALING IN CORTICOTROPES

Corticotropin-releasing hormone (CRH) stimulates ACTH secretion from a nterior pituitary corticotropes, largely but possibly not exclusively, via activation of the adenylyl cyclase cascade. CRH stimulates secret ion by increasing Ca2+ influx and by Ca2+-independent mechanisms. As C a2+ influx is largely regulated by membrane electrical properties, we review the effects of CRH on membrane excitability and changes in cyto solic Ca2+. We also speculate on possible pathways for CRH modulation of exocytosis by Ca2+ independent mechanisms. (C) 1996, Elsevier Scien ce Inc.