The rapid onset of tolerance to ataxic effects of ethanol in mice.
We have developed a precise quantal method for assessing the sensitivity to ethanol in the mouse. Mice placed on a clamped stationary horizontal dowel are scored ataxic or not ataxic depending on whether they are able to remain on the dowel during a 30-s observation period. A threshold blood ethanol concentration is determined by assaying tail blood drawn immediately upon recovery from ethanol-induced ataxia. This threshold is quite reproducible within a population of Swiss-Webster mice (coefficient of variation 9%). The precision of this method allowed us to follow the onset of rapid tolerance during a series of sequential IP ethanol doses. Tolerance persisted overnight in the absence of ethanol, and was found not to increase further with additional ethanol exposure on 2 subsequent days. The observed tolerance was shown not to be due to circadian changes in ethanol sensitivity or repeated practice on the task, indicating a true tissue tolerance.
D000818:Animals; D004305:Dose-Response Relationship, Drug; D004361:Drug Tolerance; D000431:Ethanol / Q000097:blood / Q000494:pharmacology*; D008124:Locomotion / Q000187:drug effects*; D008297:Male; D009043:Motor Activity / Q000187:drug effects; D009048:Motor Skills / Q000187:drug effects*; D009115:Muridae
D000431:Ethanol