Environmental Enrichment Reduces Stress-Induced Relapse Over Protracted Withdrawal Periods in Ethanol Taking Rats

Abstract

Although medications for alcohol addiction (e.g., acamprosate and disulfiram) show promise compared to no treatment in reducing alcohol use, it continues to fall short of being highly effective when the goal is long-term abstinence and relapse prevention. Therefore, strategies that prolong alcohol abstinence should be the primary focus of alcohol treatment research. One potential treatment strategy that could help sustain long-term alcohol abstinence is Environmental Enrichment (EE). Research has found that when stimulation or reward (EE) is derived from a source other than the drug itself, there is a reduction in the rewarding effects of the drug(s), thereby sustaining abstinence. Thus, the current studies examined if the implementation of environmental enrichment after alcohol self-administration training (a fade-in series of 2%, then 4%, and then 6% ethanol) will reduce or eliminate continued alcohol consumption in rats (abstinence) and protect against stress-induced relapse. In Experiment 1, we tested the hypothesis that EE rats will consume significantly less ethanol after different protracted abstinence periods (7 and 30 days) when compared to non-enriched (NEE) rats. In Experiment 2, we tested the hypothesis that EE will significantly reduce stress-induced ethanol consumption (relapse) after different periods of abstinence (7 and 30 days) compared to NEE rats. In Experiment 1, we found that EE significantly reduced alcohol consumption in both protracted periods of abstinence (7 and 30 days) when compared to NEE rats. In Experiment 2, we also found that EE significantly reduced ethanol consumption during the 1-hr stress-induced relapse test. Collectively, the results suggest that EE may be a promising path to pursue as a treatment strategy for long-term abstinence and emphasizes the importance of enriched life conditions in facilitating abstinence and preventing relapse to alcohol addiction.