What extremely potent alkaloid is the leading poison excreted by poison dart frogs (Phyllobates spp.)?
Batrachotoxin.
Batrachotoxin increases the permeability of nerve and cell membranes to sodium ions by binding to the alpha subunit of sodium channels, allowing rapid influx into the cells and thus blocking cell depolarization. This leads to derangements in nerve, muscle, and heart function and therefore muscle paralysis, cardiac arrhythmias, and potentially death.
Finol-Urdaneta RK et al. Batrachotoxin acts as a stent to hold open homotetrameric prokaryotic voltage gated sodium channels. J Gen Physiol 2019 Feb 4: 151(2): 186-199. doi: 10.1085/jgp.201812278
Submitted by: Abigail Sharpe, PharmD on behalf of Acute and Intensive Care Section
Posted in Question Of The Day