Cyanamide reduces brain catalase and ethanol-induced locomotor activity: is there a functional link?

The present study was designed in an attempt to assess a previously suggest ed role of brain catalase activity in ethanol-induced behaviour by examinin g ethanol-induced locomotor activity in cyanamide-treated mice. Mice were p retreated with IP injections of the catalase inhibitor cyanamide (3.75, 7.5 , 15, 30 or 45 mg/kg) or saline. Following this treatment, animals in each group received IP injections of ethanol (0.0, 1.6, 2.4 or 3.2 g/kg) and loc omotion was recorded. Several time intervals (0, 5, 10, 15, 20 or 25 h) bet ween the two treatments were also evaluated. Results indicated that cyanami de administration produced a dose-dependent decrease in ethanol-induced loc omotor activity that depends on the time between treatments. However, cyana mide did not change spontaneous or d-amphetamine-induced locomotor activity . Moreover, an additive effect of cyanamide and another brain catalase inhi bitor, 3-amino-1,2,4-triazole (AT), on the reduction of ethanol-induced loc omotor activity was observed. Perfused brain homogenates of mice treated wi th cyanamide, AT or cyanamide+AT showed a significant reduction of brain ca talase activity. The dose and time patterns of both effects were closely re lated and a significant correlation between them was obtained. These result s suggest that cyanamide could reduce locomotor activity through its inhibi tion of brain catalase, giving further support to the notion that brain cat alase may be an important regulator of some ethanol-induced behavioural eff ects.