Reinforcing Effects of MDMA (‘Ecstasy’) in Drug-Naive and Cocaine-Trained Rats
Pharmacology – January 01, 2001
Source: OpenAlex
Summary
MDMA, commonly known as ecstasy, demonstrated similar reinforcing effects in both drug-naive rats and those trained with cocaine, with doses ranging from 0.032 to 10 mg/(kg·injection). In this study involving a fixed ratio schedule of reinforcement, MDMA sensitized rats to its own effects without influencing their response to cocaine. Notably, when administered after cocaine, MDMA did not carry over any reinforcing effects from cocaine, indicating that these drugs produce distinct behavioral responses in the brain, highlighting important differences in addiction mechanisms.
Abstract
3,4-Methylenedioxymethamphetamine (MDMA; ‘ecstasy’) is one of the most prevalent illegal drugs of abuse among European adolescents, a population not generally experienced with respect to ‘hard’ drugs such as cocaine. We, therefore, determined the reinforcing effect of intravenously self-administered MDMA in a fixed ratio 1 time-out 150 s schedule of reinforcement in rats that were truly drug naive and compared it to cocaine-trained rats. The reinforcing effect of MDMA [0.032–10 mg/(kg·injection)] did not differ between drug-naive rats and cocaine-trained ones. MDMA sensitized the animals to its own rate-increasing effect but not to that of cocaine. When MDMA was tested after cocaine, there was no carryover of cocaine’s reinforcing effect to that of MDMA, suggesting that MDMA and cocaine produce distinct interoceptive stimuli in rats.