There are ∼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
β-neurotoxins and those affecting the postsynaptic membrane are called α-neurotoxins.
α-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.
KEYWORDS
Snake neurotoxins - neuromuscular junction - myokymia
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Robert L LewisM.D.
Department of Neurology, Robert C. Byrd Health Sciences Center, West Virginia University
One Medical Center Drive, Morgantown, WV 26505
