The development of tolerance to ataxia and to diuresis induced by ethanol in rats is not simultaneous.

The present study was conducted to determine whether behaviorally accelerated development of tolerance to the disruptive effects of ethanol on rotarod performance paralleled the development of tolerance to ethanol-induced diuresis and to determine the effect of pre- and post-training ethanol administration on the development of tolerance to both of these effects. Male Wistar rats were treated with ethanol (2 g kg-1 day-1, ip) over a period of 5 weeks under one of the following schemes: ethanol injections before training (pre-training ethanol group) or after training (post-training ethanol group). Control animals received 0.9% NaCl, ip, after training. The effect of ethanol on diuresis was assessed once a week. Data are reported as means +/- SEM of 6 animals. Significant tolerance to the uncoordinating effect of ethanol was detected from the 17th day of treatment onwards in animals of the pre-training ethanol group (2nd day = 1.7 +/- 0.6 s vs 17th day = 39.0 +/- 8.1 s, Student t-test for related samples) but was not observed in animals of the post-training ethanol group until 34 days of treatment (pre-training ethanol group = 56.1 +/- 8.5 s; post-training ethanol group = 29.8 +/- 9.6 s vs control group = 12.6 +/- 7.6 s, Newman-Keuls test).(ABSTRACT TRUNCATED AT 250 WORDS)