Determinants of the voluntary consumption of nicotine by rats

The 2-bottle free-choice method was used to study the voluntary consumption of nicotine by rats. Rats consumed nicotine voluntarily at different, albe it quite consistent, amounts. Voluntary intakes were higher in younger than older rats, but were not affected by gender. A previously forced nicotine intake had no effect on a subsequent voluntary intake of nicotine in older but increased it in younger rats. Forced exposure to nicotine of pregnant a nd lactating rats did not increase the voluntary intake by their offsprings . Established free-choice drinking patterns of nicotine were not affected b y a temporary forced intake of this substance. The 2-bottle choice proved t o be a reliable method to study the voluntary intake of nicotine, and resul ts suggest that nicotine is not 'addictive' per se, but that its use is app arently determined by the response of an individual rat to this substance. Copyright (C) 2000 S. Karger AG, Basel.