When examining ethanol-induced tolerance, it has been reported that with a high dose of ethanol (2.5 g/kg) rapid tolerance is observed in P and HAD1 rats but not in NP and LAD1 rats, whereas HAD2 and LAD2 rats did not differ in the development and expression of tolerance to the motor impairing effects of ethanol (Suwaki et al., 2001). Similar findings were found when rapid tolerance to moderate-dose ethanol-induced motor impairment was examined (Suwaki et al., 2001). One of the few studies that has examined nonethanol-associated consummatory behavior (Overstreet et al., 1997a) reported that food intake did not differentiate HAD’s, P’s and AA’s from their low alcohol-consuming counterparts, whereas water intake differentiated P’s from NP’s but did not differentiate HAD’s and AA’s from their low alcohol-consuming counterparts (also see Files et al., 1998; Samson et al., 1998). In the late 90’s, two studies were conducted that examined operant self-administration of ethanol by AA, HAD1, HAD2 and P rats, as well as their low alcohol-consuming counterparts (Files et al., 1998; Samson et al., 1998). We will only discuss the findings from
