Effects of drugs on tremor and increase in brain acetylcholine produced by oxotremorine in the rat

Abstract

1 In rats the effect of drugs on oxotremorine tremor and oxotremorine-induced increase in brain acetylcholine has been investigated. 2 Reserpine, (±)-α-methylmetatyrosine and diethyldithio-carbamic acid, drugs which have in common the ability to decrease tissue noradrenaline concentration, inhibited oxotremorine tremor without preventing the oxotremorine-induced increase in brain acetylcholine. 3 (±)-p-chlorophenylalanine, a depletor of tissue 5-hydroxytryptamine, did not inhibit oxotremorine tremor. 4 Phenoxybenzamine and propranolol inhibited oxotremorine tremor, and propranolol was without effect on oxotremorine-induced increase in brain acetylcholine. 5 The toxicity of oxotremorine was increased by reserpine and phenoxybenzamine. 6 The significance of these findings is discussed with regard to the mode of action of oxotremorine.