NBQX, A SELECTIVE ANTAGONIST OF THE AMPA RECEPTOR, AFFECTS NEITHER FIELD POTENTIALS NOR LONG-TERM POTENTIATION IN-VIVO

NBQX ihydroxy-6-nitro-7-sulfamoyl-benzo(F)quinoxaline), a selective an tagonist of AMPA (alpha wamino-3-hydroxy-5-methyl-4-isoxazole propiona te) receptors, at an anticonvulsant dose of 40 mg/kg (i.p.), was shown in vivo to have no effects on either the field potentials in the piri form cortex or those in the dentate gyms of the hippocampus. The same dose of NBQX also exerted no significant effects on long-term potentia tion in the hippocampus. These results suggest that the mechanism unde rlying the anticonvulsant action of NBQX in vivo does not involve a su ppressive action on physiological synaptic transmission. The possible clinical usefulness of AMPA receptor antagonists as antiepileptic drug s is suggested.