The effect of alcohol upon "muscle pull" of mice.

Equipment is described for measuring the pull exerted by mice to escape tail restraint and enter a black box. Alcohol, at doses exceeding about 2.5 g/kg, intraperitoneally, significantly decreased "muscle pull", measured 5-60 min after administration. Fifty per cent depression of muscle pull was obtained with doses of about 3.04, 3.18 and 3.55 g/kg of alcohol, 15, 30 and 60 min after alcohol administration, respectively. Depression of muscle pull correlated with alcohol concentrations in the blood plasma. The data show that muscle pull was decreased in only a few animals with plasma alcohol concentrations of less than about 250 mg%, but was significantly depressed in animals with plasma alcohol concentrations of 350 mg% or more. Although differing from it in some respects, the method described is similar to the tilting-plane method which has been used in studies dealing with the effect of alcohol in rats and mice.