ABSTRACT
Objective To investigate the effects of ketamine on the expression of NMDA receptor-1(NRⅠ)in a rat model of focal cerebral ischemia and the possible mechanism of the neuroprotection.Methods Forty healthy male SD rats weighing 250-290g were randomly divided into 2 group(n=20 each):groupⅠketamine and groupⅡpentobarbital.The aminals were anesthetized with intraperitoneal ketamine 60 mg?kg~(-1) in groupⅠor pentobarbital 40 mg?kg~(-1) in groupⅡ.Focal cerebral ischemia was produced by permanent middle cerebral artery occludion(MCAO).The animals were killed at 24 h and 72 h of MCAO and their brains removed for determination of infarct size,the number of living neurons in the penumbra and the expression of NRⅠprotein(immuno- histochemistry).Results The infarct size was significantly smaller;the number of living neurons in penumbra significantly larger and NRⅠexpression significantly down-regulated in ketamine group than in pentobarbital group.Conclusion Ketamine can protect the brain against ischemia through downregulation of NMDA receptor-1.