RESUMO
Objective To investigate the effects and mechanism of dexmedetomidine hydrochloride preconditioning against glutamate-induced neurotoxicity.Methods The model of glutamate-induced neurotoxicity was established by the injection of glutamate into lateral cerebral ventricle.Thirty-six SD rats were randomly divided into control group (C group),glutamate-induced neurotoxicity group (G group),Dex1 group and Dex2 group.Dex1 group and Dex2 group received intraperitoneal injection of dexmedetomidine respectively at a dose of 50 μg/kg or 100 μg/kg before glutamate application.Two hours later,the rats were sacrificed and hippocampus was separated to measure the level of SOD and MDA.The rest of each brain was used to measure the degree of brain edema.Pathological changes were observed under microscope with Nissl's staining.Results In contrast to G group,brain edema and MDA concentration in Dex1 group and Dex2 group were significant lower,while SOD concentrations were significantly increased and the pathological change in Dex1 group and Dex2 group were relieved obviously compared to glutamate-induced neurotoxicity group.Conclusion Dexmedetomidine preconditioning can significantly attenuate glutamate-induced neurotoxicity,which is properly related to the inhibition of oxidative-stress reaction.