Effects of Genotype and Prior Consumption of Alcohol on Rates of Ethanol-1-14C Metabolism in Mice

Previous findings of strain differences in alcohol-drinking behavior of mice, and a positive relation between the activity of liver alcohol dehydrogenase and the alcohol-drinking behavior of mice, suggested the hypothesis that alcohol- choosing behavior may be a function of the ability to metabolize alcohol. Rates of ethanol-1-14C conversion to 14CO2 were determined in male mice (60 to 87 days old), of strains C57BL/Crgl (N=10), C57BL/6J (N=24), DBA/2Crgl (N=10) and DBA/2J (N=24). Mice of each strain were injected with varying amounts (1.106, 2.212, 0.292, 0.592 and 1.185 g per kg of mouse) of ethanol-1-14C and the maximum rate of ethanol metabolism over a 30-minute period was determined. In 4 of the 5 experiments, C57BL mice metabolized alcohol at a significantly faster rate than DBA/2 mice (p<.01). The rate was about 10% higher in the C57BL mice. To test the hypothesis that prolonged consumption of alcohol will increase the rate of alcohol metabolism, the rate of conversion of ethanol-1-14C to 14CO2 was determined in C57BL mice which had previously been maintained with 10% alcohol as sole drinking fluid for about 90 days. Results of 2 separate experiments, in which all mice (150 days old) were injected with 0.553 g of ethanol-1-14C per kg of mouse, showed that mice which had ingested the substrate subsequently metabolized alcohol at a significantly faster rate than their water-fed controls (p<.01). The average maximum rates of ethanol oxidation over a 30-min period by the experimental and control mice were 0.153 (N=10) and 0.133 (N=10) µmole per min per g, respectively, in one experiment; and 0.185 (N=6) and 0.171 (N=6) µmole per min per gin the other.