Adolescent Rearing Conditions Influence the Relationship Between Initial Anxiety-Like Behavior and Ethanol Drinking in Male Long Evans Rats
Article first published online: 24 AUG 2012
Copyright © 2012 by the Research Society on Alcoholism
Alcoholism: Clinical and Experimental Research
Volume 37, Issue Supplement s1, pages E394–E403, January 2013
How to Cite
Chappell, A. M., Carter, E., McCool, B. A. and Weiner, J. L. (2013), Adolescent Rearing Conditions Influence the Relationship Between Initial Anxiety-Like Behavior and Ethanol Drinking in Male Long Evans Rats. Alcoholism: Clinical and Experimental Research, 37: E394–E403. doi: 10.1111/j.1530-0277.2012.01926.x
- Issue published online: 15 JAN 2013
- Article first published online: 24 AUG 2012
- Manuscript Accepted: 21 JUN 2012
- Manuscript Received: 19 MAR 2012
- National Institutes of Health. Grant Numbers: AA 17056, AA 17531, AA 10422
- Social Isolation;
Rodent studies have demonstrated that adolescent social isolation results in many behavioral perturbations, including increases in anxiety-like behaviors. Socially isolated (SI) rats have also been shown to self-administer greater amounts ethanol (EtOH) in some, but not all, studies. Here, we tested whether juvenile social isolation increases EtOH drinking using an intermittent procedure that engenders relatively high intake in normally reared animals. We also compared the behavioral phenotype of rats reared under social isolation or group-housed conditions with adult rats housed under conditions commonly used in EtOH-drinking studies.
Male Long Evans rats were procured immediately postweaning and were group housed for 1 week. Subjects were then randomly divided into 2 groups: SI rats, housed individually for 6 weeks and group-housed (GH) rats (4/cage). A third group was procured as young adults and was housed individually upon arrival for 1 week (standard housing condition). Rats were then tested in a plus-maze and novelty assay, and then, all subjects were singly housed and EtOH drinking was assessed.
SI rats displayed increased anxiety-like behaviors on the plus-maze, a greater locomotor response to a novel environment, and increased EtOH intake, relative to GH rats. Age-matched standard housed (STD) rats exhibited an anxiety-like behavioral profile on the plus-maze that was similar to SI, and not GH rats, and also drank EtOH at levels comparable with SI subjects. In addition, anxiety-like behavior on the plus-maze correlated with intermittent EtOH intake in SI and GH rats.
These data further support the validity of the rodent juvenile social isolation model for studies directed at elucidating behavioral and neurobiological mechanisms linking anxiety and EtOH drinking. These findings further suggest that housing conditions commonly employed in rodent drinking studies may recapitulate the anxiety-like and EtOH-drinking phenotype engendered by a juvenile social isolation procedure.