Voltage-gated Ca2+ current in pancreatic B-cells.

Voltage-dependent inward Ba++ and Ca++ currents were recorded in cultured neonatal rat pancreatic islet cells using the whole-cell voltage clamp technique. Outward current was suppressed by internal Cs+ and ATP and external TEA. Inward currents activated rapidly and decayed to a variable extent. The current decay was particularly marked when using long duration or large depolarizing pulses. Currents were due to Ca++ channel activation since they were abolished by omitting Ba++ and Ca++ or including Co++.