Amnesia produced by intracerebroventricular injections of hemicholinium-3 in mice was prevented by pretreatment with piracetam-like compounds.

Intracerebroventricular (ICV) injections of hemicholinium-3 (HC-3) to mice before the training trial in a passive avoidance task produced an amnesic effect at the 24-hour retention test. Pretreatment by IP injection of piracetam, etiracetam, or pramiracetam, 30 minutes before HC-3 injections antagonized the amnesic effects of HC-3. Pretreatment with choline was not effective. The depletion of cerebral acetylcholine by the HC-3 injection was not prevented by piracetam or etiracetam.