Mobilization of different pools of glucose-incorporated calcium in pancreatic beta-cells after muscarinic receptor activation.

Muscarinic receptor activation resulted in a biphasic mobilization of Ca2+ from isolated pancreatic islets. Glucose was essential for preparing the beta-cells to respond with the initial stimulatory phase. This effect seems to depend on the ability of the sugar to promote active sequestration of Ca2+ in the endoplasmic reticulum.