Enhancement of conditioned place preference response to cocaine in rats following subchronic administration of 3,4-methylenedioxymethamphetamine (MDMA)

Rats given the recreational drug MDMA (ecstasy) for four days later showed a stronger conditioned place preference for cocaine than rats given a placebo, indicating that prior MDMA exposure may increase sensitivity to cocaine's rewarding effects and potentially raise the risk of cocaine addiction.

Study at a glance

Abstract

In this study, we measured conditioned place preference (CPP) responses to cocaine following subchronic administration of the recreationally abused drug (+/-)-3,4-methylenedioxymethamphetamine (MDMA, "ecstasy") in male Sprague-Dawley rats. Animals were given either vehicle (1 ml/kg of distilled water, s.c.) or MDMA (20 mg/kg, s.c.) twice a day for 4 consecutive days. Two weeks later, CPP responses to cocaine (5, 10, or 20 mg/kg, i.p.) were measured. The MDMA-treated animals showed a significantly greater CPP response to cocaine than the vehicle-treated animals. Since conditioned place preference is believed to be a measure of appetitive behavior, these results suggest that MDMA abuse could lead to an increased vulnerability to the rewarding actions of cocaine and, hence, to increased vulnerability to cocaine addiction and dependence.