Various studies using GABAA receptor modulators in inbred, selectively bred, and recombinant inbred strains that differ in ethanol responses have correlated GABAA receptor action to innate ethanol tolerance. For instance, mice selectively bred for differences in diazepam responses also differed in ethanol responses. Mice that were more resistant to diazepam were less ataxic to ethanol, compared to diazepam-sensitive mice (Gallaher and Gionet 1988). The GABAA receptor agonist taurine may also be involved in different ethanol-related responses in Sardinian alcohol-preferring (sP) rats versus non-preferring (sNP) rats. Recent microdialysate studies indicate that sP rats had reduced ethanol-related taurine release compared to sNP rats (Quertemont et al. 2000). Notably, alcohol-preferring rats were less sensitive to the sedative-hypnotic effects of ethanol (Kurtz et al. 1996); therefore, it is possible that differences in ethanol-related behaviors in these animals may be related to differences in endogenous GABAA receptor ligands like taurine or responses to other GABAA receptor modulators. Indeed, extrasynaptic receptors involved in tonic inhibition have recently been shown to be sensitive to low concentrations of taurine (Jia et al. 2008a). However, sP and sNP rats
