GRIN2B and schizophrenia: Both the mRNA and protein expressions of the GluN1 and GluN2C subunits in the prefrontal cortices of patients with schizophrenia were significantly decreased in comparison to that in healthy controls, whereas changes in the other subunits, such as GluN2A, GluN2B, GluN2D, and GluN3, in the prefrontal cortex were not observed [73,74].