Solinas Marcello, Chauvet Claudia, Thiriet Nathalie, El Rawas Rana, Jaber Mohamed
Institut de Physiologie et Biologie Cellulaires, Université de Poitiers, Centre National de la Recherche Scientifique, Poitiers F-86022, France.
Proc Natl Acad Sci U S A. 2008 Nov 4;105(44):17145-50. doi: 10.1073/pnas.0806889105. Epub 2008 Oct 27.
Environmental conditions can dramatically influence the behavioral and neurochemical effects of drugs of abuse. For example, stress increases the reinforcing effects of drugs and plays an important role in determining the vulnerability to develop drug addiction. On the other hand, positive conditions, such as environmental enrichment, can reduce the reinforcing effects of psychostimulants and may provide protection against the development of drug addiction. However, whether environmental enrichment can be used to "treat" drug addiction has not been investigated. In this study, we first exposed mice to drugs and induced addiction-related behaviors and only afterward exposed them to enriched environments. We found that 30 days of environmental enrichment completely eliminates behavioral sensitization and conditioned place preference to cocaine. In addition, housing mice in enriched environments after the development of conditioned place preference prevents cocaine-induced reinstatement of conditioned place preference and reduces activation of the brain circuitry involved in cocaine-induced reinstatement. Altogether, these results demonstrate that environmental enrichment can eliminate already established addiction-related behaviors in mice and suggest that environmental stimulation may be a fundamental factor in facilitating abstinence and preventing relapse to cocaine addiction.
环境条件可显著影响滥用药物的行为和神经化学效应。例如，压力会增强药物的强化作用，并在决定成瘾易感性方面发挥重要作用。另一方面，诸如环境丰富化等积极条件可降低精神兴奋剂的强化作用，并可能提供针对药物成瘾发展的保护作用。然而，环境丰富化是否可用于“治疗”药物成瘾尚未得到研究。在本研究中，我们首先使小鼠接触药物并诱导出与成瘾相关的行为，之后才将它们置于丰富环境中。我们发现，30天的环境丰富化完全消除了对可卡因的行为敏化和条件性位置偏爱。此外，在条件性位置偏爱形成后将小鼠饲养在丰富环境中，可防止可卡因诱导的条件性位置偏爱恢复，并减少参与可卡因诱导恢复的脑回路的激活。总之，这些结果表明环境丰富化可消除小鼠中已确立的与成瘾相关的行为，并表明环境刺激可能是促进戒毒和预防可卡因成瘾复发的一个基本因素。
