Inhibition of the acetylcholine receptor by histrionicotoxin.
1 The action of C5-decahydrohistrionicotoxin (C5-HTX) has been investigated on the extrajunctional acetylcholine (ACh) receptors of denervated rat muscle. 2 C5-HTX causes both a rapid and slow reduction in amplitude of iontophoretic ACh potentials evoked at all frequencies from the extrajunctional receptors. 3 C5-HTX also causes a time-dependent inhibition of the iontophoretic potentials evoked at frequencies greater than 0.02 Hz. This inhibition was observed either alone or superimposed upon desensitization, and may be caused by a similar mechanism to desensitization.
D000109:Acetylcholine / Q000037:antagonists & inhibitors / Q000494:pharmacology / Q000502:physiology*; D000200:Action Potentials / Q000187:drug effects; D000664:Amphibian Venoms / Q000494:pharmacology*; D000818:Animals; D005260:Female; D066298:In Vitro Techniques; D009119:Muscle Contraction / Q000187:drug effects; D010880:Piperidines / Q000494:pharmacology; D051381:Rats; D011950:Receptors, Cholinergic / Q000187:drug effects*; D013997:Time Factors
D000664:Amphibian Venoms; D010880:Piperidines; D011950:Receptors, Cholinergic; D000109:Acetylcholine; C007948:histrionicotoxin