Atwater I, Frankel B J, Rojas E, Grodsky G M
Q J Exp Physiol. 1983 Apr;68(2):233-45. doi: 10.1113/expphysiol.1983.sp002715.
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, steady-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.
将灌注大鼠胰腺中葡萄糖诱导的胰岛素释放与小鼠胰岛β细胞膜电位的葡萄糖诱导变化进行了比较。在存在11.1 mM葡萄糖的情况下，将细胞外Ca和Mg的浓度以阶梯形式同时或分别从正常水平的10%变化到200%。Ca的变化引起电活动的瞬时变化，同时胰岛素释放也发生瞬时变化。如果维持Ca/Mg比值，在10%至200%的Ca浓度之间，稳态胰岛素释放保持恒定，而电活动则显示出变化。爆发参数分析表明，Ca内流的增加或减少由兴奋性的降低或增加来平衡。据推测，β细胞含有一种调节Ca内流的补偿机制。
