Effects of priming injections of MDMA and cocaine on reinstatement of MDMA- and cocaine-seeking in rats
- 作者：Susan Schenk ; Lincoln Hely ; David Gittings ; Barbara Lake ; Evangeline Daniela
- 关键词：MDMA ; Cocaine ; Self-administration ; Relapse ; Drug-seeking
- 刊名：Drug and Alcohol Dependence
- 出版年：2008
- 期刊代码：81_03768716
- 类别：med
- 出版时间：1 August 2008
- 卷：96
- 期：3
- 页码：249-255
- 文件大小：278 K
摘要
Exposure to self-administered drugs is sufficient to produce drug-seeking in animal models. In many cases priming injections of drugs that share discriminative stimulus properties with the self-administered drug also can lead to drug-seeking, suggesting that exposure might precipitate relapse. The present investigation examined the ability of MDMA or cocaine priming injections to reinstate extinguished drug-seeking in rats. Priming injections of cocaine (0–20.0 mg/kg) and MDMA (0.0–10.0 mg/kg) reinstated extinguished drug-taking for both the cocaine- and MDMA-trained rats. In a separate group of cocaine-trained rats that received repeated exposure to 10.0 mg/kg MDMA, the initial exposure to MDMA (10.0 mg/kg, IP) failed to reinstate extinguished responding but MDMA became an effective prime for reinstatement of extinguished cocaine-taking behavior with repeated exposure. Effects of MDMA in MDMA-trained rats was greater than the effect in cocaine-trained rats suggesting that extensive experience with MDMA self-administration might have sensitized rats to this effect. These findings show that extinguished MDMA self-administration, like self-administration of other drugs of abuse, can be reinstated by exposure to psychostimulants thereby precipitating relapse.