Environmental enrichment during adolescence heightens ethanol intake in female, but not male, adolescent rats that are selectively bred for high and low ethanol intake during adolescence

SUÁREZ, ANDREA; FABIO, MARÍA CAROLINA; BELLIA, FABIO; FERNÁNDEZ, MACARENA SOLEDAD; PAUTASSI, RICARDO MARCOS

The American Journal of Drug and Alcohol Abuse

Taylor & Francis Group

Lugar: Londres; Año: 2020 p. 1 - 12

0095-2990

Background: Discriminating between adolescents who willeventually have ethanol use problems from those who do not is important.Environmental enrichment is a promising approach to reduce drug-relatedproblems, but its impact on ethanol?s effects and intake is being scrutinized.Objective: We tested the effects of environmental enrichment on ethanol intake,preference, and anxiety-like response as well as shelter seeking andrisk-taking behaviors. Methods: Experiment 1 examined ethanol intake,preference, and anxiety-like responses in 46male and 54 female Wistar rats thatwere derived from a short-term breeding program that selected for high andlowethanol drinking during adolescence (ADHI2 andADLO2 lines, respectively).Shelter-seeking and risk- taking behaviors were assessed (Experiment 2) inADHI2 and ADLO2 rats (73 males, 76 females) reared under environmentalenrichment or standard housing conditions and given doses of ethanol (2.5 g/kg,intraperitoneal) for 3 weeks. Environmental enrichment was applied on postnataldays 21?42. Ethanol intake was measured on postnatal days 42?68. Anxiety-likebehavior and exploratory responses were assessedusingthelight-darkboxandmultivariate concentricsquarefield test. Results: InExperiment 1, environmental enrichment increased ethanol intake in female, butnot male, ADHI2 and ADLO2 rats (p < 0.05). In the baseline measurement ofExperiment 2, ADHI2 rats exhibited reduced risk-taking and increasedanxiety-like behavior (p < .05). After exposure to environmental enrichmentthe ADHI and ADLO rats, both males and females, exhibited increased risk-takingand exploratory behavior (p < 0.05). Conclusions: Environmental enrichmentappears to increase ethanol intake in female rats by promoting the explorationof new environments or stimuli. The findings indicate that environ- mentalenrichment increased ethanol intake in female, but not male, rats. Clinicalprograms that treat alcohol use disorder by emphasizing environmentalstimulation should be designed with caution