Nootropic drugs have different effects on kindling-induced learning deficits in rats.

Kindling represents an accepted model of human epileptogenesis. Furthermore, it has been demonstrated that kindled rats show a diminished learning performance in an active avoidance task. In our study we administered different nootropic drugs to kindled rats to test their effects on learning a two-way active avoidance task in the shuttle-box. Kindling was induced by repeated intraperitoneal injections of 45 mg kg-1 pentylenetetrazol (PTZ) once every 48 h. The substances vinpocetine (0.1 and 1.0 mg kg-1), methylglucamin orotate (225 and 450 mg kg-1), piracetam (100 mg kg-1), and meclofenoxate (100 mg kg-1) were administered during kindling development and after kindling completion prior to each session in the learning experiment. The nootropic drugs had little if any effect on severity of seizures. Concerning their effect on learning the substances each acted in a specific manner. Methylglucamin orotate enhanced the learning deficit induced by kindling. Meclofenoxate injected prior to the kindling stimulation was ineffective, whereas administration prior to the learning test improved the learning performance effectively. A complementary action was shown in experiments with vinpocetine. Only piracetam prevented the occurrence of kindling-induced learning deficits regardless the administration schedule.