Effects of selective forebrain depletions of norepinephrine and serotonin on the activity and food intake effects of amphetamine and fenfluramine.

Selective forebrain depletions of either norepinephrine or serotonin were produced in separate groups of rats by placement of lesions in the brainstem noradrenergic area and in the dorsal and median raphé nuclei respectively. Rats with norepinephrine depleting lesions exhibited an attenuation relative to intact animals of both the anorexic and locomotor stimulatory effects of amphetamine. In contrast, depletion of serotonin by the raphé lesion enhanced the locomotor stimulation induced by amphetamine but did not affect the anorexic efficacy of amphetamine. Neither brain lesion, however, reliably altered the animals' response to either the anorexic or activity effects of fenfluramine.