The effect of selective lesioning of brain catecholamine-containing neurons on the activity of various anorectics in thr rat.

An intraventricular injection of 6-hydroxydopamine to rats pretreated with pargyline, a procedure which produces a marked decrease of brain catecholamines without significant changes in the serotonin levels, significantly antagonizes the anorectic effect of amphetamine, phentermine, mazindol and diethylpropion, while the reduction of food intake induced by other drugs such as fenfluramine, p-chloroamphetamine, SE 780 and SKF 1-39728 is not significantly affected. The data suggest an involvement of brain catecholamines in the anorectic effect of amphetamine, phentermine, mazindol and diethylpropion whereas other mechanisms appear to be involved in the activity of the other anorectics studied.