The blockade of NMDA receptor ion channels by ketamine is enhanced in developing rat cortical neurons

► Effects of ketamine on NMDAR-mediated EPSCs are tested in neonatal and adult neurons. ► Ketamine blocks NMDAR-mediated EPSCs more greatly in neonatal neurons. ► Ketamine produces a longer blockage on NMDAR-mediated EPSCs in neonatal neurons. ► Higher vulnerable to ketamine-induced neurotoxicity in the developing brain is linked.