Fig. 2.
Batrachotoxin disrupts Nav channel gating. BTX is found in particular frog species (silhouette of Phyllobates bicolor on the left) and has a complex molecular structure (middle). At 5 μM, BTX completely inhibits fast inactivation of rNav1.8 currents evoked from a holding potential of −90 mV to a voltage of −20 mV when expressed in Xenopus oocytes. During the second voltage step to −30 mV, channels normally close; however, BTX-bound channels are still deactivating. Black is control and red is after addition of TTX (right)