LATERALIZED EFFECTS OF ETHANOL ON AGGRESSION AND SEROTONERGIC SYSTEMSIN ANOLIS-CAROLINENSIS

The lateralized effects of ethanol (ETOH) upon behavior and monoamine biochemistry in the lizard, Anolis carolinensis, were examined. Eight adult male anoles consumed solutions of 19% ethanol (ETOH) twice daily over the course of 18 days, while controls consumed water. ETOH decre ased the use of the left eye/right hemisphere, but not the right eye/l eft hemisphere, during territorial aggression (p < 0.05). During cross over (i.e., ETOH to water and vice versa) this effect was reversible a nd replicable. Biochemically, an asymmetry was observed in 5-HT levels in the raphe both in ETOH and controls. ETOH increased levels of sero tonin (5-HT; p < 0.05), and 5-HIAA/5-HT ratios (p < 0.05) in the raphe ; serotonin levels in several brain regions correlated with aggressive responses. These results suggest that ETOH boosts 5-HT levels in anim als subchronically exposed to ETOH. They further suggest that asymmetr y in endogenous 5-HT systems may account for the asymmetrical regulati on of aggression generally, and may explain the behavioral effects of ETOH upon lateralized aggression. (C) 1998 Elsevier Science B.V. All r ights reserved.