GsMTx-4 inhibits NaV1.7 channel currents expressed in Xenopus oocytes. NaV1.7 currents were elicited by 100 ms voltage ramp from a holding potential of -100 mV to +30 mV, applied every 10 sec using whole-cell voltage clamp technique. Left: Superimposed traces of NaV1.7 currents before (black) and during (green) application of 500 nM GsMTx-4 (ab141871). Right: GsMTx-4 dose response inhibition of NaV1.7 currents.