Inhibition of Transient K+ Current by Copper in Drosophila Neurons

The transient K1 current (IKA) affects the rate of repetitive action potentials. The whole-cell patch-clamp technique was applied to cultured Drosophila neurons derived from embryonic neuroblasts. IKA was measured from neurons before and after application of 0.1 mM copper to the external saline. IKA was smaller in the copper-containing saline (12.0 ± 1.6 pA) than in the control saline (37 ± 6.5 pA). Activation and inactivation of IKA were unchanged by copper. These results suggest that copper can influence neuronal excitability and may affect neuronal function.