Presynaptic and musculotropic effects of a basic phospholipase A2 from the Formosan habu (Trimeresurus mucrosquamatus) venom.
A basic phospholipase A2 purified from the venom of a crotalid snake (Trimeresurus mucrosquamatus) was applied to chick and mouse neuromuscular preparations. The enzyme at lower concentrations (1-3 micrograms/ml) blocks neuromuscular transmission at a presynaptic site, while at higher concentrations (10-30 micrograms/ml) it causes contracture and depolarization of the muscle as well. It is concluded that the mode of action of the enzyme on vertebrate nerve-muscle transmission is similar to that of notexin and ceruleotoxin from elapid snake venoms.
D000818:Animals; D002642:Chick Embryo; D003435:Crotalid Venoms / Q000494:pharmacology*; D009045:Motor Endplate / Q000187:drug effects; D009132:Muscles / Q000187:drug effects*; D009466:Neuromuscular Blocking Agents / Q000494:pharmacology; D010740:Phospholipases / Q000494:pharmacology*; D010741:Phospholipases A / Q000494:pharmacology*; D054467:Phospholipases A2; D013569:Synapses / Q000187:drug effects*
D003435:Crotalid Venoms; D009466:Neuromuscular Blocking Agents; C029748:Trimeresurus venoms; D010740:Phospholipases; D010741:Phospholipases A; D054467:Phospholipases A2