N-methyl-D-aspartate (NMDA) receptors are a class of ionotropic glutamate-gated ion channels. These
receptors have been shown to be involved in long-term
potentiation, an activity-dependent increase in the
efficiency of synaptic transmission thought to underlie
certain kinds of memory and learning. NMDA receptor
channels are heteromers composed of the key receptor
subunit NMDAR1 (GRIN1) and 1 or more of the 4 NMDAR2
subunits: NMDAR2A (GRIN2A), NMDAR2B (GRIN2B), NMDAR2C (GRIN2C) and NMDAR2D (GRIN2D).