Autoinhibition of acetylcholine binding to Torpedo electroplax; a possible molecular mechanism for desensitization.
Binding of [(3)H]acetylcholine (measured by equilibrium dialysis) to a particulate preparation of Torpedo electroplax exhibits autoinhibition at concentrations higher than 1 muM. It is suggested that autoinhibition results from acetylcholine binding to regulatory sites on its receptor macromolecules. This binding causes the change to a new and inactive conformation and rejection of acetylcholine bound to the larger number of active sites. The relationship to the physiological phenomenon of desensitization is discussed.
D000109:Acetylcholine / Q000378:metabolism*; D000818:Animals; D001345:Autoradiography; D001665:Binding Sites; D003956:Dialysis; D004557:Electric Organ / Q000502:physiology*; D005399:Fishes; D011950:Receptors, Cholinergic; D011955:Receptors, Drug; D009435:Synaptic Transmission; D014316:Tritium
D011950:Receptors, Cholinergic; D011955:Receptors, Drug; D014316:Tritium; D000109:Acetylcholine