Induction and maintenance of ethanol self-administration without food deprivation in the rat.

Rats were trained to lick at a drinking tube containing 5% ethanol to obtain access to a 0.1-ml dipper containing 20% sucrose. Following 20 of these drinking sessions, a lever press response was shaped and maintained with ethanol presentation in the dipper. This induction procedure resulted in rats responding on a FR 8 schedule of reinforcement to receive 40% (v/v) ethanol. Ethanol intakes over 0.5 g/kg in 30 min were obtained when ethanol concentrations over 10% were available. These intakes frequently resulted in blood ethanol levels over 100 mg ethanol/dl blood. This contingent sucrose induction procedure did not use food deprivation at any time. It is suggested that this procedure can be used to investigate the processes involved with the initiation of ethanol as a reinforcer independent of food restriction procedures.