[Effects of piracetam during prolonged use in an experiment].

The spectrum of the pharmacological activity of piracetam administered for a long time was studied in experiments on mice and rats. It was established that administration of piracetam (300-400 mg/kg i. p.) for 10-42 days brought about potentiation of its antiamnestic effect, retardation of the processes of extinction, an increase in the emotional responsiveness, and preservation of the tranquilizing effect with no side effects (sedative or myorelaxant). The characteristic feature of piracetam effect on the extinction is its ability to decelerate this process only after its prolonged administration. It is assumed that under prolonged administration of piracetam there takes place the formation of a new functional system ensuring the memory trace stabilization.