However, previous autoradiographic studies showed that binding of glutamate to the NMDAR was significantly decreased, particularly in the CA1 field [38, 39, 40, 41, 42], and immunoblot, reverse transcription‐polymerase chain reaction and immunohistochemical approaches have also described a reduction in the GluN1 protein expression in AD brains [43, 44, 45, 46], consistent with the data as described in our study. The gene discussed is GRIN1; the disease is Alzheimer disease.