The N-methyl-D-aspartate receptor (NR), a subtype of ion-tropic glutamate receptor, provides sites for phosphorylation and for channel blocking. NRs are composed of NR1 and NR2A-D subunits.

• 现已发现NMDAR至少存在7个亚单位,即NR1亚单位、4种NR2亚单位(分为NR2A、NR2B、NR2C和NR2D)以及2种NR3亚单位。