Temperature modulates ethanol sensitivity in mice: Generality across strain and sex

Findings in our laboratory indicate that body temperature alters ethanol potency as measured by sleep-time, wake-up brain ethanol concentration and mortality in male C57BL/6J mice. The current studies tested the generality of these results. Experiment one tested age-matched, drug-naive, male C57BL/6S and BALB/cS mice. Experiment two tested age-matched, drug-naive, male and female C57BL/6J mice. Each mouse was injected IP with 3.6 g/kg ethanol (20% w/v). After losing its righting reflex, the mouse was placed into a v-shaped sleep tray within a chamber kept at a designated temperature from 12 to 36°C. Upon awakening, rectal temperature was measured and blood and brain samples were taken for gas chromatographic analysis. As in previous studies, ambient temperature modulated the body temperatures and sleep-times of intoxicated animals. More important, wake-up rectal temperatures were positively correlated with sleep-times and negatively correlated with wake-up ethanol concentrations in all animals tested. These results support the hypothesis that brain sensitivity to ethanol depression varies with body temperature in accordance with membrane perturbation theories of anesthesia.