GRIN2B and Anxiety: Consistent with this, GEG also attenuated expression of excitotoxic N-methyl-D-aspartate (NMDA) receptor subunits GRIN2B and GRIN2C in the frontal cortex and hypothalamus, thereby reflecting impaired neuroplasticity and neurotoxicity that have been implicated in pain hypersensitivity and anxiety [69,70].