NS-1643 enhances KV11.1 (hERG) currents in Xenopus oocytes. A. Time course of current amplitude at -40 mV (see B for the voltage stimulating protocol) before, during application of 10 and 30 µM NS-1643 (ab141825) (indicated by bars) and upon wash, demonstrating the current amplitude enhancement. B. Superimposed example traces of KV11.1 channel current responses, before and during application of 10 and 30 µM NS-1643. Currents were elicited by 500 ms voltage step from -100mV to -10 mV followed by a 200 ms step to -40 mV (demonstrated on top) , applied every 10 sec.