CD38 is a transmembrane glycoprotein, which catalyzes the synthesis and hydrolysis of cyclic ADP-ribose (cADPR), a calcium-mobilizing agent that acts independently of inositol trisphosphate. Pancreatic islets were obtained from pancreas of male Balb/c mice weighing 15∼20 g by a collagenase technique. NAD-pretreated isolated islets showed decreased insulin secretion triggered by glucose and inactivated hydrolytic activity of NAD glycohydrolase of CD38 due to ADP-ribosylation. Our results suggest that CD38 has a pivotal role in signal transmission between glucose stimulus and Ca2+-induced insulin secretion.

Keywords: CD38, NAD, Insulin secretion, ADP-ribosylation