NR2A (Glutamate [NMDA] receptor subunit epsilon-1 or NMDAR2A) is a glutamate-gated ion channel with high calcium permeability and voltage-dependent sensitivity to magnesium. The NMDA channel is involved in long-term potentiation, an activity-dependent increase in synaptic transmission underlying memory and learning. NR2A is a heteromer composed of a zeta subunit (GRIN1), an epsilon subunit (GRIN2A, GRIN2B, GRIN2C or GRIN2D) and a third subunit (GRIN3A or GRIN3B). NR2A activation requires binding of agonist to both types of subunits.