The ethanol-induced open-field activity in rodents treated with isethionicacid, a central metabolite of taurine

The effect of isethionic acid, a central metabolite of taurine, on ethanol- induced locomotor activity was investigated in rodents. Ten minutes followi ng an (IP) simultaneous administration of ethanol (0.0, 1.5, 2.0, 2.5, 3.0, 3.5g/kg) and isethionic acid (0.0, 22.5, 45.0, 90.0, 180.0mg/kg), mice wer e placed in the open-field chambers and locomotor activity was measured dur ing a ten-minute testing period. A significant interaction was found betwee n isethionic acid and ethanol. Isethionic acid pre-treated mice (45.0, 90.0 and 180.0mg/kg) showed a higher locomotor activity than the saline group a t 2.5 and 3g/kg of ethanol. In a second study, isethionic acid (45mg/kg) an d ethanol (1g/kg) were simultaneously injected to rats. Ten minutes after t he two treatments, rats were placed in the open-field chamber for a 30- min ute period. The depressant effects that ethanol produced on rat locomotion were amplified by the same dose of isethionic acid as it affected ethanol-i nduced locomotion in mice (45mg/kg). However, isethionic acid did not chang e the spontaneous locomotion at any of the doses tested in mice or rats. Si nce no differences in blood ethanol levels were detected in both mice and r ats, the interaction between isethionic acid's action and ethanol-related l ocomotion does not seem to be due to different rates of absorption of ethan ol or any other pharmacokinetic process related to ethanol levels. The curr ent study displayed that isethionic acid, administered intraperitoneally, b ehaves in a similar way to its immediate precursor, taurine, by amplifying ethanol-induction of the locomotor activity.