These alcohol-preferring [Alko Alcohol (AA)] and alcohol-avoiding [Alko Non-Alcohol (ANA)] rats were developed from a closed-colony of a Wistar–Sprague–Dawley cross foundation stock in Helsinki, Finland (Eriksson, 1968). The lines were revitalized with the Brown-Norway and Lewis lines in the late 1980’s and returned to selective breeding (Sommer et al., 2006). As an animal model of alcoholism, AA rats readily consume appreciable levels of ethanol (>5.0 g of ethanol/kg body weight/day), whereas ANA rats avoid ethanol (<1.0 g/kg/day) when food and water are available ad libitum (Ritz et al., 1986). The AA rat will operantly self-administer ethanol, indicating they find ethanol reinforcing and will work for access to ethanol (Files et al., 1997, 1998; Samson et al., 1998). Free access to ethanol results in increased ethanol elimination rate (metabolic tolerance) for AA, but not ANA, rats (Forsander and Sinclair, 1992), and AA rats develop and display greater functional tolerance to the motor-impairing, hypothermic and hypnotic effects of ethanol than ANA rats after repeated ethanol injections (Lê and Kiianmaa, 1988). In addition, the AA rat displays a modest ADE following short deprivation
