title: Effects of stonefish (Synanceia trachynis) venom on murine and frog neuromuscular junctions.
abstract: The neuromuscular toxicity of stonefish (Synanceia trachynis) venom was characterized by electrophysiological and electron microscopic examination of isolated murine and frog nerve-skeletal muscle preparations exposed to various concentrations of venom. Low concentrations of venom (2.5-10 micrograms/ml) acted presynaptically by causing release and depletion of neurotransmitter from the nerve terminal. The response was Na+ channel-independent (resistant to tetrodotoxin), required the presence of either Ca2+ or Mg2+, and was observed with botulinum neurotoxin-paralyzed nerve-muscle preparations. Higher concentrations of venom (100-300 micrograms/ml) acted postsynaptically and presynaptically. They caused irreversible depolarization of muscle cells and microscopically observable muscle and nerve damage. We conclude that the previously observed neuromuscular toxicity of stonefish venom is a consequence of the venom's dose-dependent, presynaptic and postsynaptic actions at the myoneural junction.
authors: Medical Sciences Research Institute, Herndon, Virginia 22071.
authors: A S
authors: AS
authors: Kreger
authors: J
authors: J
authors: Molgó
authors: J X
authors: JX
authors: Comella
authors: B
authors: B
authors: Hansson
authors: S
authors: S
authors: Thesleff
mesh_terms: D000109:Acetylcholine / Q000378:metabolism; D000818:Animals; D001905:Botulinum Toxins / Q000494:pharmacology; D002462:Cell Membrane / Q000187:drug effects / Q000648:ultrastructure; D004594:Electrophysiology; D005397:Fish Venoms / Q000494:pharmacology*; D005399:Fishes / Q000378:metabolism*; D066298:In Vitro Techniques; D008297:Male; D051379:Mice; D008854:Microscopy, Electron; D009045:Motor Endplate / Q000187:drug effects / Q000648:ultrastructure; D009132:Muscles / Q000473:pathology; D009411:Nerve Endings / Q000187:drug effects / Q000378:metabolism / Q000648:ultrastructure; D009467:Neuromuscular Depolarizing Agents / Q000494:pharmacology; D009469:Neuromuscular Junction / Q000187:drug effects* / Q000648:ultrastructure; D011893:Rana esculenta; D051381:Rats; D017207:Rats, Sprague-Dawley; D013569:Synapses / Q000187:drug effects / Q000378:metabolism / Q000648:ultrastructure
chemical_list: D005397:Fish Venoms; D009467:Neuromuscular Depolarizing Agents; D001905:Botulinum Toxins; D000109:Acetylcholine