Electrical characteristics of the beta-cells in pancreatic islets.

1. The electrical activity of beta-cells is characterized by a regular burst pattern. 2. The bursts occur in a potential range which is not dependent on external glucose concentration. However, there is a clear dose-response relationship between spike frequency or plateau duration and the glucose concentration. 3. There is a striking biphasic pattern of the electrical activity in response to a sudden and sustained stimulation with glucose. 4. These findings agree well with corresponding investigations on insulin release and strongly support the view that insulin release and electrical activity are directly correlated. 5. Concerning the mechanism of the electrical activity, there is evidence that an electrogenic pump plays an important role in the regulation of the burst pattern and presumably in the regulation of insulin release.