The poison Dart frog's batrachotoxin modulates Nav1.8

Batrachotoxin is a potent modulator of voltage-gated sodium channels, leading to irreversible depolarisation of nerves and muscles, fibrillation, arrhythmias and eventually cardiac failure. Since its discovery, field researchers also reported numbness after their skin came into contact with this toxin. Intrigued by this phenomenon, we determined the effect of batrachotoxin on the voltage-gated sodium channel Nav1.8, which is considered to be a key player in nociception. As a result, we discovered that batrachotoxin profoundly modulates this channel: the inactivation process is severely altered, the voltage-dependence of activation is shifted towards more hyperpolarised potentials resulting in the opening of Nav1.8 at more negative membrane potentials and the ion selectivity is modified.