Chunk #33 — 4. Selectively bred high alcohol-consuming rat lines and their phenotypic characteristics — 4.4. Sardinian alcohol-preferring and alcohol-nonpreferring rats
ethanol’s anxiolytic effects (Colombo et al., 1995; Roman and Colombo, 2009). Additionally, sP, but not sNP, rats find ethanol rewarding as indicated by locomotor activation after limited free-choice access to ethanol (Colombo et al., 1998b) and administration of low doses of ethanol (Agabio et al., 2001). Ethanol-naïve sP and sNP rats display similar levels of ethanol clearance (Quertemont et al., 2000). However, chronic free-choice ethanol drinking by sP rats results in the development of functional tolerance to the motor impairing effects of ethanol (Colombo et al., 2006). At variance with the other lines of alcohol-preferring rats, sP rats are more sensitive to the motor-impairing and sedative/hypnotic effects of ethanol than sNP rats (Colombo et al., 2000b). Additionally, when intermittently exposed to 20% alcohol such that access is given every other day, sP rats display marked escalations in daily alcohol intake (approximately 10 g/kg/day), with signs of alcohol intoxication and behavioral dependence displayed (Loi et al., 2010). Thus, the sP line meets many of the criteria put forth for an animal model of alcoholism.
