NORADRENERGIC RATHER THAN SEROTONERGIC BASIS OF REWARD IN DORSAL TEGMENTUM

Obtained high rates of self-stimulation (1000/8 min. and higher) in the dorsal tegmentum in the vicinity of the dorsal nucleus of the raphe and medial longitudinal fasciculus. Ss were 6 male albino Sprague-Dawley rats. These rates were increased by systemic administration of the noradrenergic releaser, D-amphetamine, and decreased by the noradrenergic blocker, chlorpromazine. They were unaffected by the serotonin depleter, DL-p-chlorphenylalanine, at time of maximal depletion. Dorsal tegmental reward may be due to stimulation of ascending noradrenergic fibers of passage near the dorsal longitudinal fasciculus rather than stimulation of serotonergic cell bodies of the dorsal nucelus of the raphe. (19 ref.) (PsycINFO Database Record (c) 2006 APA, all rights reserved). © 1969 American Psychological Association.