Changes in the elimination and resurgence of alcohol-maintained behavior in rats and the effects of naltrexone.

Resurgence may be a mechanism of relapse in alcohol use disorder patients upon discharge from treatment as part of an abuse-treatment-relapse cycle. Adjunctive pharmacotherapies may be a means to facilitate behavioral treatments and block resurgence. Experiments were conducted using a model of alcohol self-administration to assess the repeatability of the elimination and resurgence of alcohol-maintained behavior and the effects of naltrexone. Experiments had three phases. In Phase 1, behavior was maintained by oral alcohol under a fixed-ratio schedule. In Phase 2, behavior was extinguished via condensed milk delivery under a differential-reinforcement-of-other-behavior (DRO) schedule. In Phase 3, the DRO schedule was eliminated. In Experiment 1, this 3-phase cycle was replicated 4 times. Across replications, response rates and dose of alcohol consumed did not differ in Phase 1, alcohol-maintained behavior was eliminated more rapidly in Phase 2, and the resurgence effect was generally stable in Phase 3. In Experiment 2, naltrexone was administered in Phase 2, Phase 3, or both Phases 2 and 3, to separate groups of rats. Naltrexone facilitated the elimination of alcohol-maintained behavior in Phase 2 and, the resurgence of alcohol-maintained behavior was reduced only for those rats that received naltrexone in both phases. Together, these experiments demonstrate that the resurgence of alcohol-maintained behavior is replicable within-subjects and, further, resurgence of alcohol-maintained behavior may be a useful model to evaluate pharmacological interventions to facilitate behavioral treatments and reduce the likelihood of relapse. Results with naltrexone support the use of medication-assisted therapy approaches to reduce relapse risk in patients. (PsycINFO Database Record (c) 2020 APA, all rights reserved).