TOLERANCE AND DEPENDENCE IN HIGH ALCOHOL SENSITIVITY (HAS) AND LOW ALCOHOL SENSITIVITY (LAS) RATS AFTER CHRONIC ALCOHOL INTOXICATION BY INHALATION

In rats selected for their differences in sleep time followingacute administration of ethanol (high or low alcohol sensitivity:HAS or LAS), alcohol chronic tolerance and behavioural dependencewere determined. Tolerance was assessed by calculating the intervalbetween the loss and regain of the righting reflex followingan acute administration of ethanol (4 g/kg body wt), after intoxicationby inhalation of ethanol vapour for 3 weeks. The impoetanceof behavioural dependence was estimated by measuring the ethanolintake in a free-choice situation water/ethanol (10% v/v), afterintoxication by inhalation for 4 weeks. The two HAS and LASlines did n show any behavioural dependence, while they developeda significant tolerance to the hypnotic effect of ethanol, whichwas more marked for the LAS line.