GRIN2B and brain injury: Notably, a cell penetrant form of the peptide (TAT-CBD3): (1) induced NR2B internalization in dendritic spines without altering somal NR2B surface expression; (2) reduced NMDA-mediated Ca2+ influx and currents in cultured neurons; and (3) decreased hippocampal neuronal death in the controlled cortical impact model of traumatic brain injury [9].