Effect of NMDA receptor subunits NR2A and NR2B on transient brain ischemia/reperfusion-induced neuronal death in rat hippocampus

Objective To investigate the role of NR2A,NR2B [the subunits of N-methyl-D-asparate(NMDA) receptor] on the neuronal death induced by transient cerebral ischemia. Methods Transient (15 min) brain ischemia was induced by the four-vessel occlusion in Sprague Dawley rats. The antisense oligodeoxynucleotides (ODNs) of NR2A and NR2B were used to suppress the expression of NR2A and NR2B by intracerebroventricular intracerebroventricular infusion once per day for 3 days before ischemia. After 5 days reperfusion,the rats were perfusion -fixed with paraformaldehyde and cresyl violet staining was used to examine the survival of CA1 pyramidal cells of the hippocampus. Results Both NR2A and NR2B antisense ODNs showed a protective effect against neuronal cell death induced by cerebral ischemia/reperfusion.Furthermore,NR2A antisense ODNs had more protective effect on the neuronal death than NR2B antisense ODNs(P0.05). ConclusionBoth NR2A and NR2B subunits play an important role in neuronal death induced by cerebral ischemia followed by reperfusion.