β CELL MEMBRANE POTENTIAL AND INSULIN RELEASE; ROLE OF CALCIUM AND CALCIUM: MAGNESIUM RATIO
- 7 April 1983
- journal article
- research article
- Published by Wiley in Quarterly Journal of Experimental Physiology
- Vol. 68 (2) , 233-245
- https://doi.org/10.1113/expphysiol.1983.sp002715
Abstract
Glucose-induced insulin release from perfused rat pancreas was compared with glucose-induced changes in membrane potential of .beta.-cells from mouse islets. Extracellular concentrations of Ca and Mg were varied as steps, simultaneously or separately, from 10 to 200% of normal in the presence of 11.1 mM glucose. A change in Ca induced a transient change in electrical activity paralleled by a transient change in insulin release. If the Ca/Mg ratio was maintained, stedy-state insulin release remained constant between 10 and 200% Ca, while electrical activity showed alterations. Analysis of burst parameters indicated that increased or decreased Ca entry was balanced by decreased or increased excitability. It is postulated that the .beta.-cell contains a compensator mechanism for the regulation of Ca influx.This publication has 1 reference indexed in Scilit:
- Interaction of Calcium and Glucose on Glucagon SecretionEndocrinology, 1976