NBQX DOES NOT AFFECT LEARNING AND MEMORY TASKS IN MICE - A COMPARISON WITH D-CPPENE AND IFENPRODIL

The alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA) antagonist 2,3-dihydroxy-6-nitro-7-sulfamoyl-(benzo(F)-quinoxaline (NBQX) did not impair working memory measured as alternation behavior in the Y-maze in mice. No depressant effect on alternation was detected even when NBQX impaired locomotion measured as the total number of arm entries. Similar profile of action in the Y-shaped maze was observed after administration of an anti-ischemic drug ifenprodil. In contrast, the N-methyl-D-aspartate (NMDA) antagonist (D-(E)-4-(3-phosphonoprop-2-enyl)piperazine-2-carboxylate (D-CPPene) impaired spontaneous alternation. In the step-through passive avoidance task, mice were trained to avoid dark compartment entry. NBQX and ifenprodil did not impair learning in this task when administered before or immediately after training. In contrast, D-CPPene disturbed acquisition when administered before but not immediately after training or before retention test. These observations suggest that AMPA receptors are not critically involved in the formation of spatial working memory and acquisition (storage) in the passive avoidance, and have no effect on recall (retrieval) from long-term memory.