Effects of Chronic Alcohol Consumption on Hippocampal Anatomy and Associated Behaviors in Three Inbred Strains of Mice

The goal of this study was to investigate the influence of 6 months of chronic alcohol consumption on hippocampal neuroanatomy, notably the sizes of the intra- and infrapyramidal mossy fiber (IIPMF) terminal fields, and several behaviors, such as radial-maze learning, intermale aggression and anxiety-like behavior, in three inbred strains of mice (NZB, CBA/H, C57BL/6). Based upon several reports highlighting the toxicity of chronic alcohol exposure on the hippocampus, we expected a general diminution of cognitive abilities, with reduced spatial learning skills, increased aggression and anxiety; and concomitantly, a reduction in the sizes of the IIPMF. Contrary to our hypothesis, we did not find an effect of chronic alcohol exposure, neither an effect per se or in interaction with the genotype. Possible explanations for this unexpected finding include ageing effects and species differences between rats and mice.