PEAQX tetrasodium hydrate (NVP-AAM007) is a competitive antagonist of the N-methyl-D-aspartate (NMDA) receptor. This compound shows high selectivity for NR1 and NR2A subunits of the receptor compare to NR2B subunit1. PEAQX IC50 values for acting on the NR1 and NR2A subnits were dependent on glutamate concentration used to evoke response. An IC50 value of 215 ± 13 nM was demonstrated in the presence of the EC50 concentration of glutamate whereas a value of 2.2 ± 0.14 μM was shown with higher glutamate concentrations
