Persistent High Alcohol Consumption in Alcohol-Preferring (P) Rats Results from a Lack of Normal Aversion to Alcohol

Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Box 3412, Durham, NC 27710, USA.
Alcohol and Alcoholism (Impact Factor: 2.89). 03/2010; 45(3):219-22. DOI: 10.1093/alcalc/agq020
Source: PubMed


In this study, we tested the impact of pretreatment with alcohol on subsequent alcohol drinking in outbred Sprague-Dawley and selectively bred alcohol-preferring (P) rats.
As a pretreatment, male Sprague-Dawley and P rats were given a passive oral administration of either alcohol (1.0 g/kg) or tap water. Then, they were given free choice of drinking alcohol (5% v/v) or water in their home cages, which was measured over 4 weeks.
Without alcohol pretreatment, there was no significant strain difference in alcohol preference; both strains preferred 5% (v/v) alcohol solution. The strain difference was only apparent in the groups given alcohol pretreatment. This arose from the fact that alcohol pretreatment significantly reduced alcohol preference in the Sprague-Dawley rats to a level well below 50%, while it did not alter drinking behavior in P rats. The same effects were seen with total alcohol consumption (g/kg/day). These effects persisted throughout the 4 weeks of the study.
The principal difference between the Sprague-Dawley and P rats was that the P rats did not show the normal aversion to alcohol after forced exposure to alcohol that the Sprague-Dawley rats showed. One of the potential contributors to high alcohol intake and preference in P rats may be lack of sensitivity to aversive effects of alcohol.

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Available from: Amir H Rezvani, Oct 13, 2014
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