Effects Of Sufentanil Preconditioning On Cerebral Ischemia-reperfusion Injury In Rats

Objective To investigate the effects of sufentanil preconditioning on cerebralischemia-reperfusion injury in rats.Methods Seventy male SD rats were randomly divided into five groups. Sham group（group Sham）、ischemia-reperfusion group （group I\R）and different concentrations ofsufentanil preconditioning groups （group L, M, H）.The rats in group I\R and group L, groupM, group H received normal saline and sufentanil infusion int-ravenously at0.5g.kg^-1,1.5g.kg^-1and4.5g.kg^-1in the regime （3×5min infusion with5min interval） beforecerebral ischemia. Four-vessel occlusion was used to establish the global cerebralischemia-reperfusion model in the study groups.An acute experimental cerebral ischemia ratmodel was induced for15min.24hours after reperfusion, each group randomly selected eightrats to measure the brain water content, serum S-100β protein and total calcium of braintissue.The rest of each group were planed to observe light microscope and electron microscopeof the hippocampus CA1.Results （1） There were no significant differences in neurological scores among thefive groups after ischemia-reperfusion24hs（p>0.05）.（2） The brain water content,serumS-100β protein and total calcium of brain tissue:①Compared with group sham, The brainwater content in group I\R, group L and group H were increased significantly（p<0.01）, therewas no significant difference in group M compared with Sham（p>0.05）;serum S-100βprotein of group I\R,group L, group M and group H were increased significantly（p<0.01）,the total calcium of brain tissue in group I\R,group L, group M and group H were increased（p<0.05）, group I\R,group L and group H increased significantly（p<0.01）.②Compared with group I\R, the brain water content,serum S-100β protein and total calciumof brain tissue in group L, group M and group H were decreased（p<0.05）, group M andgroup H decreased significantly（p<0.01）.③Compared with group L, the brain watercontent,serum S-100β protein and total calcium of brain tissue in group M were decreased（p<0.05）, total calcium of brain tissue in group H were decreased（p<0.05）.④Comparedwith group M, the brain water content in group H were increased（p<0.05）.（3）Lightmicroscope showed: Group sham: morphology of the cell was integrity withoutkaryopycnosis. Group I\R: morphology of the cell was far beyond integrity with severekaryopycnosis and edema. Group L, Group M and Group H: morphology of the cell wasirregular with mild karyopycnosis and edema.（4） Electron microscope observation: Groupsham: the nuclear membrane was regular and nucleolus uniform; swelling and degranulationwere not observed in rough endoplasmic reticulum. Group I\R: the nuclear membrane wasdestroyed seriously which manifested as serious retraction, pyknosis, as well as severeswelling and degranulation of rough endoplasmic reticulum. Group L: the nuclear membranewas destroyed mildly which manifested as mild retraction and nucleolus uniform; swellingand degranulation were observed mildly in rough endoplasmic reticulum. Group M: thenuclear membrane was destroyed mildly which manifested as mild retraction and nucleolusuniform; swelling and degranulation were observed occasionally in rough endoplasmicreticulum. Group H: the nuclear membrane was destroyed mildly which manifested as mildretraction and nucleolus uniform; swelling and degranulation were observed mildly in roughendoplasmic reticulum.Conclusion Sufentanil preconditioning can protect cerebral against ischemia-reperfusion injury in rats, especially at the dose of1.5g.kg^-1...