Nicotine-induced behavioral disinhibition and ethanol preference correlateafter repeated nicotine treatment

This study investigated the effects of repeated daily nicotine (0.35 mg/kg; 15 days) treatment on behavioral inhibition and locomotor activity in the elevated plus-maze and on voluntary ethanol consumption. When challenged wi th nicotine before: the test, rats pretreated with repeated nicotine spent more time on and made more entries onto the open arms of an elevated plus-m aze than did vehicle-pretreated animals. The ethanol preference and intake, measured during 3 h after a nicotine injection, was also higher in the nic otine-pretreated animals. In ethanol consumption experiments, there was a p ositive correlation between the % time and % entries made onto open arms vs . the ethanol preference and intake. However, no correlation between the to tal number of entries made in the elevated plus-maze and the measures of et hanol consumption was observed. These findings suggest that the ability of repeated nicotine administration to increase ethanol consumption is related to development of a nicotine-induced reduction of inhibitory control rathe r than development of locomotor sensitization. (C) 2001 Published by Elsevi er Science B.V.