Kv2.1 ablation alters glucose-induced islet electrical activity, enhancing insulin secretion.

ABSTRACT: Voltage-gated potassium currents (Kv), primarily due to Kv2.1 channels, are activated by glucose-stimulated pancreatic beta cell depolarization, but the exact role (or roles) of this channel in regulating insulin secretion remains uncertain. Here we report that, compared with controls, Kv2.1 null mice have reduced fasting blood glucose levels and elevated serum insulin levels. Glucose tolerance is improved and insulin secretion is enhanced compared to control animals, with similar results in isolated islets in vitro. Isolated Kv2.1(-/-) beta cells have residual Kv currents, which are decreased by 83% at +50 mV compared with control cells. The glucose-induced action potential (AP) duration is increased while the firing frequency is diminished, similar to the effect of specific toxins on con

SUBMITTER: Jacobson DA 

PROVIDER: S-EPMC2699758 | biostudies-literature | 2007 Sep

REPOSITORIES: biostudies-literature