Regulation of calcium in pancreatic α- and β-cells in health and disease
Rorsman P., Braun M., Zhang Q.
The glucoregulatory hormones insulin and glucagon are released from the β- and α-cells of the pancreatic islets. In both cell types, secretion is secondary to firing of action potentials, Ca 2+ -influx via voltage-gated Ca 2+ -channels, elevation of [Ca 2+ ] i and initiation of Ca 2+ -dependent exocytosis. Here we discuss the mechanisms that underlie the reciprocal regulation of insulin and glucagon secretion by changes in plasma glucose, the roles played by different types of voltage-gated Ca 2+ -channel present in α- and β-cells and the modulation of hormone secretion by Ca 2+ -dependent and -independent processes. We also consider how subtle changes in Ca 2+ -signalling may have profound impact on β-cell performance and increase risk of developing type-2 diabetes. © 2011 Elsevier Ltd.