Snake venoms and the neuromuscular junction

Abstract

There are approximately 420 venomous species of snakes living on the earth. Their venoms, each unique, can affect multiple organ systems. The venoms have a predilection for the peripheral nervous system where the neuromuscular junction is a favorite target. Those venoms affecting the release of acetylcholine from the presynaptic membrane are called beta-neurotoxins and those affecting the postsynaptic membrane are called alpha-neurotoxins. alpha-Bungarotoxin has been used in quantitative studies of acetylcholine receptor density and turnover and for the assay of antibodies directed against the acetylcholine receptor. A unique feature of timber rattlesnake venom is its ability to cause clinical myokymia. This likely results from a blockade of voltage gated K+ antibodies.