A cell-permeable peptide mimetic of the GluN2B PSD-95 interaction domain (a PDZ ligand) designed to reduce NMDAR–nNOS coupling via PSD-95 is neuroprotective in stroke models in rodents and monkeys62,63 and successfully completed a phase II trial for safety and efficacy for iatrogenic micro-strokes during cerebral aneurysm repair64. This evidence concerns the gene DLG4 and brain aneurysm.