Effects of exercise on ethanol-induced hypothermia and loss of righting response in C57BL/6J mice.

C57BL/6J mice were given 5 weeks of voluntary wheel running and then studied for ethanol (EtOH) sensitivity as indicated by EtOH-induced hypothermia and loss of righting response (LORR) after 3.8 g/kg EtOH (20% w/v). Mice were assigned to wheel (free access to a running wheel in the home cage) or no wheel conditions, and wheel counts were monitored by a computer at 5-min intervals around the clock. In Experiment 1, duration of EtOH-induced LORR was assessed as amount of time required for the animal to right itself three times in a 30-s period, and body temperature was assessed by rectal probe. Wheel animals showed significantly shorter LORR and significantly less hypothermia at regaining the righting response than no wheel controls. In Experiment 2, temperature was assessed at 45 and 90 min after EtOH challenge. Baseline temperatures for wheel and no wheel animals did not differ, but wheel animals showed dramatic resistance to EtOH-induced hypothermia at both time points. Together with our earlier work, these results provide evidence that prior exercise can offset the effects of EtOH intoxication in several domains of EtOH sensitivity.