Guangxitoxin-1E inhibits KV2.1 channel currents expressed in Xenopus oocytes. Currents were elicited by application of voltage ramp from a holding potential of -80 mV to 60 mV in 100 msec, delivered every 10 seconds. A. Time course of channel activity (current amplitude at +40 mV), before (black) and during (green) application of 100 nM Guangxitoxin-1E (ab141872). B. Top, illustration of the voltage ramp protocol. Bottom, example of superimposed current traces before (black) and during (green) application of 100 nM Guangxitoxin-1E, taken from the experiment in A.