Different affinity of cortical GHB binding sites in sardinian alcohol-preferring (sP) and -non preferring (sNP) rats

Specific gamma-hydroxybutyric acid (GHB) binding sites in cortical membranes of selectively bred alcohol-preferring sP and alcohol-non preferring sNP rats were compared using [2,3(-3)H]GHB ligand. The sP rat line showed an increased affinity (approximately 40% lower Kd) of both the high- and low-affinity sites in comparison with the sNP line. No significant difference in GHB receptor density (Bmax) was detected between the two rat lines. The results raise the possibility that differences in GHB binding sites may play a role in the genetic predisposition to ethanol preference in our rat line.