title: Action of colchicine and cytochalasin B on the acetylcholine receptor.
abstract: 1. The effects of colchicine and cytochalasin B have been investigated on the extrajunctional acetylcholine (ACh) receptors of rat muscle. 2. Colchicine and cytochalasin B each decreased the amplitude and rise time of the iontophoretic ACh potential. When the dose of ACh was increased in the presence of these agents, ACh potentials were produced with a biphasic waveform consisting of a fast initial phase and a second slow phase. 3. It is proposed that colchicine and cytochalasin B are acting through a mechanism other than the breakdown of microtubules and microfilaments.
mesh_terms: D000109:Acetylcholine / Q000378:metabolism*; D000818:Animals; D002038:Bungarotoxins / Q000494:pharmacology; D003078:Colchicine / Q000494:pharmacology*; D003571:Cytochalasin B / Q000494:pharmacology*; D005071:Evoked Potentials / Q000187:drug effects; D005260:Female; D006207:Half-Life; D066298:In Vitro Techniques; D009121:Muscle Denervation; D009132:Muscles / Q000187:drug effects; D051381:Rats; D011950:Receptors, Cholinergic / Q000187:drug effects*; D014403:Tubocurarine / Q000494:pharmacology
chemical_list: D002038:Bungarotoxins; D011950:Receptors, Cholinergic; D003571:Cytochalasin B; D000109:Acetylcholine; D003078:Colchicine; D014403:Tubocurarine