TY - JOUR T1 - Intra-Accumbal Injection of CART (Cocaine-Amphetamine Regulated Transcript) Peptide Reduces Cocaine-Induced Locomotor Activity JF - Journal of Pharmacology and Experimental Therapeutics JO - J Pharmacol Exp Ther SP - 1038 LP - 1044 DO - 10.1124/jpet.103.052332 VL - 307 IS - 3 AU - Jason N. Jaworski AU - Marie A. Kozel AU - Kelly B. Philpot AU - Michael J. Kuhar Y1 - 2003/12/01 UR - http://jpet.aspetjournals.org/content/307/3/1038.abstract N2 - Evidence suggests that CART (cocaine-amphetamine regulated transcript) peptides are mediators or modulators of the actions of psychostimulant drugs. In this study, the effects of intra-accumbal injections of rat long form (rl) CART 55-102 were examined. Injection of the peptide alone had no effect, but pretreatment with the peptide blunted or reduced the locomotor-inducing effects of cocaine after an i.p. injection. This effect was dose related and time limited, as expected. rlCART 1-27, a CART peptide fragment not active in other studies, was without effect on cocaine-induced locomotor activity. Because the actions of cocaine involve dopamine, the effect of rlCART 55-102 on dopamine-induced locomotor activity was examined. Intraaccumbal injection of dopamine produced a dose-related and time-limited increase in locomotor activity, as expected. Coinjection of rlCART 55-102 with dopamine blunted the effect. In summary, these data suggest that CART peptides in the nucleus accumbens would tend to oppose the actions of cocaine. The American Society for Pharmacology and Experimental Therapeutics ER -