Mesolimbic gender differences in peptide CART mRNA expression: effects of cocaine

THE putative neurotransmitter peptide CART has been suggested to be involve d in the actions of psychostimulants. We analyzed the CART mRNA expression in mesolimbic brain areas of male and ovariectomized 17 beta-estradiol- (30 mu g) and vehicle-treated female rats. A gender difference was noted in th e accumbens shell during basal conditions; male rats expressed higher level s of CART mRNA than both female groups. Following binge cocaine; injections (3 x 15 mg/kg), elevated levels were found in the central amygdala of male but not female rats. In the medial accumbens shell CART mRNA was elevated after cocaine, but only in the non-treated females. The present results sup port a role of mesolimbic CART in psychostimulant drug action. NeuroReport 10:3449-3452 (C) 1999 Lippincott Williams & Wilkins.