Oxiracetam prevents the MK-801 induced amnesia for the elevated plus-maze in mice

We investigated the effect of the nootropic substance oxiracetam on the impairment of memory induced in mice by the non-competitive NMDA antagonist MK-801. Memory capacities of animals having different experience were evaluated using the elevated plus-maze test. Oxiracetam was injected immediately after the acquisition session(s), MK-801 was given 30 min before the retention session which followed 24 h after the acquisition session(s). In slightly experienced animals (Section 3.1), oxiracetam (3 and 30 mg/kg, s.c.) prevented MK-801 (0.15 mg/kg, i.p.) induced memory deficits characterized by a prolongation of the transfer latency. In well-trained animals (Section 3.2), oxiracetam (30 mg/kg, s.c.) attenuated MK-801 (0.15, 0.25 and 0.4 mg/kg, i.p.) induced amnesia for a spatial orientation in the elevated plus-maze. These results show that oxiracetam interacted with the glutamatergic NMDA receptor system and forestalled the impairment of retrieval of long-term memory. The results also justify the usage of the elevated plus-maze method in the evaluation of potential anti-amnesic or nootropic drugs. (C) 2000 Elsevier Science B.V. All rights reserved.