description
At resting membrane potential the NMDA receptor is blocked by extracellular Mg2+ ions and therefore is not activated in this state by ligands (glutamate, glycine, NMDA). The voltage block is removed upon depolarization of the post-synaptic cell membrane by the influx of Na+ and efflux of K+ from the cell, Mg2+ is expelled from the NMDA receptor can now be activated by the ligands. The depolarization of the membrane maybe due to activation of Ca2+ impermeable AMPA receptors, which facilitates Na+ influx, contributing to the unblocking of NMDA receptors

external resources
NCBI:1268799
REACTOME:R-HSA-438066
PUBMED:9481670

genes
ACTN2 , CAMK2A , CAMK2B , CAMK2D , CAMK2G , DLG4 , GRIA1 , GRIA2 , GRIA3 , GRIA4 , GRIN1 , GRIN2A , GRIN2B , GRIN2C , GRIN2D , NEFL , AKAP9 ,