〔Abstract〕 Objective To investigate the effect of sevoflurane postconditioning on DNA damage and the expression of silent information regulation(SIRT1) of HT22 cell line following oxygen and glucose deprivation/reoxygenation injury. Methods Firstly, HT22 cells in logarithmic phase were randomly divided into normal control group(CON), oxygen and glucose deprivation/reoxygenation 4 h group(OGD/R 4 h), oxygen and glucose deprivation/reoxygenation 4 h+1% sevoflurane postconditioning group(OGD/R 4 h+1%SEVO), oxygen and glucose deprivation/reoxygenation 4 h+2% sevoflurane postconditioning group(OGD/R 4 h+2%SEVO), oxygen and glucose deprivation/reoxygenation 6 h group(OGD/R 6 h), oxygen and glucose deprivation/reoxygenation 6 h+1% sevoflurane postconditioning group(OGD/R 6 h+1%SEVO), oxygen and glucose deprivation/reoxygenation 6 h+2% sevoflurane postconditioning group(OGD/R 6 h+2%SEVO). Secondly, the former four groups in the first part of this study were further investigated the mechanism of sevoflurane postconditiong in oxygen and glucose deprivation/reoxygenation injury. MTT assay was used to detect cell survival rate, PI/Hoechst fluorescence staining and TUNEL assay were used to detect apoptotic and necrosis rate, immunofluorescence staining was used to detect the expression of 8-OHdG and Cleaved-casepase 3, Western blot analysis was used to detect the expression of SIRT1 and apoptotic protein expression. Results In the first part of the experiment, compared with CON group, the cell survival rates in both OGD/R 4 h and OGD/R 6 h groups reduced(P<0.01, P<0.01), and the number of apoptosis and necrotic cells also increased. Compared with the related OGD/R 4 h group, the cell survival rate in the 1% SEVO and 2% SEVO groups both increased( P<0. 01,P<0. 01),and the number of apoptotic cells and necrotic cells also decreased. Moreover,compared with the related OGD/R 6 h group,the cell survival rate in the1% SEVO and 2% SEVO groups increased( P<0. 01,P<0. 01),and the number of apoptotic cells and necrotic cells decreased. The second part of the experiment,compared with CON group,there were more TUNEL positive labeled cells,and increased expressions of Cleaved-casepase3( P<0. 01) and 8-OHdG( P<0. 01),as well as BAX( P<0. 01) in the OGD/R 4 h group,however,SIRT1 and Bcl-2 expression reduced( P<0. 01,P<0. 01).Compared with the OGD/R 4 h group,there were less TUNEL positive labeled cells,and decreased expressions of Cleaved-casepase3( P<0. 01,P<0. 01) and 8-OHdG( P<0. 01,P<0. 01),as well as BAX( P<0. 05,P<0. 01) in the 1% SEVO and 2% SEVO groups,SIRT1 and Bcl-2 expression increased( P<0. 01,P<0. 01; P<0. 05,P<0. 01). Conclusion Sevoflurane postconditioning can alleviate DNA oxidative damage and apoptosis of HT22 hippocampal neurons induced by oxygen and glucose deprivation/reoxygenation,and up-regulate SIRT1 protein expression.