Dopaminergic involvement in the effects of piracetam on foot shock induced aggression in mice.

The effects of piracetam-a nootropic drug, were studied on foot shock induced aggressive behaviour in mice. Intraperitoneal injection of piracetam resulted in a biphasic response i.e:, initial excitation followed by inhibition of the aggressive behaviour. The initial excitation was observed with only 100 and 50 mg/kg doses of piracetam and not with the lower doses (25 and 12.5 mg/kg). Dopaminergic receptor blocker haloperidol (0.5; 0.25 and 0.12 mg/kg, ip) and pimozide (1.0 mg/kg, ip) produced inhibition of the aggressive behaviour. Lowering of the dose of haloperidol to 0.06 mg/kg resulted in an excitation of the aggressive behaviour. No motor deficit or catalepsy was observed with either haloperidol or pimozide injected in the doses indicated above