DLG4 and brain ischemia: In the process of cerebral ischemia, the over-released glutamate excessively activates N-methyl-d-aspartate receptors (NMDARs) and thereby induces neuronal death [1, 6], which is caused by NMDAR-dependent neuronal nitric oxide synthase (nNOS) translocation from cytosol to membrane via the interaction of nNOS and postsynaptic density protein-95 (PSD95) [7].