Abstract
Dose-response curves constructed for the nicotinic agonists: acetylcholine, carbachol, choline, tetramethyl-ammonium, nicotine, decamethonium and dimethylpiperazinium, after treatment of chick biventer cervicis muscle preparations with a combination of rapid nerve stimulation, and the drug 2-(4-phenylpiperidino)-cyclohexanol (AH5183), were indistinguishable from control dose-response curves for these agonists. As AH5183 reduced the acetylcholine content of, and output from, chick biventer cervicis muscles after nerve stimulation, these results provide evidence that nicotinic agonists do not release acetylcholine from the same source as that released by nerve stimulation.