Behavioral effects of piracetam in rats with isolation syndrome.

Piracetam in doses of 300 and 600 mg/kg i.p. administered for 5 days in Wistar rats with isolation syndrome produced a transient inhibition of mouse-killing behavior. Its anti-aggressive effect was most pronounced on days 2 and 3 of drug administration. On day 5 all aggressive rats again exhibited mouse-killing behavior. Piracetam in both doses was less effective in avoidance learning of aggressive rats. These results suggest that piracetam has a slight effect on the aggressive behavior of rats with isolation syndrome. No relationship exists between the antiaggressive and the learning-facilitating effects of piracetam.