Evaluation of chronic alcohol self-administration by a 3-bottle choice paradigm in adult male rats. Effects on behavioural reactivity, spatial learning and reference memory

Chronic ethanol consumption is able to modify emotional behaviour and cognition in humans.In particular, the effects exerted by alcohol may depend on doses,time and modalities of administration.Inthis study we investigated,in adult male rats,ethanol self-administration and preference patterns usinga 3-bottle choice paradigm with water,10%ethanol solution,and white wine(10%,v/v),along a four-week period.The influence of alcohol free-access on novelty-induced explorative behaviour in the openfield, and on spatial learning and reference memory in the Morris water maze was also evaluated.Ourresults indicate that:(i)rats show a higher preference for alcohol,in the first two weeks of the paradigm,displaying a higher consumption of 10%ethanol solution than white wine;in the last two weeks,theyreduce their alcoholic preference,drinking the same moderate amounts of the two alcoholic beverages;(ii) at the fourth week of the free-access paradigm rats show a high explorative behaviour in the central squares of the open field and an improvement in spatial information processing in the new-placelearning task of the Morris water maze.Inconclusion our data suggest that,interestingly,rats exposed tothe free-access paradigm were able to self-regulate their alcoholic intake,and indicated that a moderatealcohol consumption was able to induce an increase in behavioural reactivity and anenhancement inspatial learning flexibility.