EtOH self-administration on shuttle box avoidance learning and extinction in rats.

The effects of ethanol on the acquisition and extinction of the two-way active avoidance response were examined in adult, male Wistar rats from two treatment groups, oral self-administration of alcohol solution (10% v/v ethanol and 3% w/v glucose in distilled water) and oral self-administration of control solution (3% w/v glucose in distilled water). Alcohol or control solutions were available 1 h per day during 15 days simultaneously with food, with free water for the rest of the day. Blood was drawn in the last day of this phase to evaluate blood ethanol levels (BEL). After this period, rats were tested in a two-bottle paradigm for 1 h per day and placed in a shuttle box immediately afterwards. This phase went lasted for 10 days. Subjects were trained to avoid an electric foot shock in the first 5 days (15 trials per day). Following this, half of the subjects were tested in an "easy extinction with punishment" (EEP) and the other half in a "difficult extinction with punishment" (DEP) of the avoidance response for the last 5 days. Alcohol accelerates the avoidance responding acquisition, and no significant effects of alcohol were seen in the extinction phase. Data are discussed in terms of the specificity of the effects of alcohol on learning.