Effects of fasciculin 2, an anticholinesterase polypeptide from green mamba venom, on neuromuscular transmission in mouse diaphragm preparations.
Fasciculin 2, a polypeptide from green mamba (Dendroaspis angusticeps) venom, causes an increase in the twitch response of mouse phrenic nerve-hemidiaphragm preparations to indirect stimulation. Intracellular recording reveals that fasciculin 2 augments neuromuscular transmission by increasing the amplitude and duration of endplate potentials. Its action is not reversed by washing. Interactions with neostigmine confirm that fasciculin 2 acts as an anticholinesterase. It has no presynaptic actions on transmitter release or postsynaptic receptor blocking actions. On chicken muscle preparations, fasciculin 2 has no anticholinesterase actions. Because of this selectivity and its apparent irreversibility, fasciculin 2 should be useful in characterizing different forms of acetylcholinesterase.
Anderson
A J
AJ
Harvey
A L
AL
Mbugua
P M
PM
D000818:Animals; D002645:Chickens; D002800:Cholinesterase Inhibitors; D003964:Diaphragm / Q000187:drug effects; D004347:Drug Interactions; D004546:Elapid Venoms / Q000008:administration & dosage / Q000494:pharmacology*; D066298:In Vitro Techniques; D008564:Membrane Potentials / Q000187:drug effects; D051379:Mice; D009388:Neostigmine / Q000008:administration & dosage; D009469:Neuromuscular Junction / Q000187:drug effects*; D010791:Phrenic Nerve / Q000187:drug effects; D012910:Snake Venoms / Q000032:analysis*; D009435:Synaptic Transmission / Q000187:drug effects*
D002800:Cholinesterase Inhibitors; D004546:Elapid Venoms; D012910:Snake Venoms; D009388:Neostigmine; C044937:fasciculin