Behavioral sensitization to ethanol in rats: evidence from the Sprague-Dawley strain.

Although it has been shown with other drugs of abuse, behavioral sensitization has not been shown with ethanol in rats. One possible reason for the negative previous findings may be due to the doses of ethanol employed in the different phases of sensitization. In the current experiment, outbred Sprague-Dawley rats were divided into either high or low responders to novelty. They were pretreated for 15 days with intraperitoneal injections of either saline or 1.0 g/kg ethanol, and then given a challenge dose of 0.25 g/kg ethanol after a 3-week period. During the first 10 min after the challenge dose, rats high in response to novelty pretreated with ethanol displayed higher locomotor activity scores relative to the other three groups. These data demonstrated evidence for behavioral sensitization with ethanol in outbred rats.