behavioral response to ethanol in a loss of righting reflex (LORR) test. Male and female wild-type and homozygous AlkKO mice were tested at two sedating doses of ethanol, 3.6 and 4.0 g/kg. At each dose of ethanol, we observed significant effects of genotype, but no effects of sex or sex by genotype interactions. Since we observed no effect of sex, we combined the LORR data for male and female mice (Figure 4B). ANOVA of the combined data demonstrated that AlkKO mice show a significant increase in the amount of time to recover the righting reflex at both doses of ethanol. Heterozygous AlkKO mice were also tested and did not show a difference compared to wild-type controls (data not shown). To determine if the difference in the LORR recovery time was due to alterations in ethanol metabolism and clearance in the AlkKO mice, we examined blood ethanol concentrations (BEC) at various time points after an injection of 4.0 g/kg ethanol (Figure 4C). No differences in the BEC were observed between genotypes. These data indicate that Alk negatively regulates ethanol-induced sedation time without affecting ethanol metabolism and clearance in mice.
