中文摘要：

目的观察地塞米松（DEX）对大鼠嗜铬瘤细胞（PCI2）细胞氧化应激损伤及对烟酰胺腺嘌呤二核苷酸磷酸氧化酶2（NOX2）表达的影响。方法体外培养的PCI2细胞随机分为正常对照组、H20：（100μmol/L）组、DEX（1、5、10[μmol／L）组。四甲基偶氮唑盐（MTT）法测细胞存活率，双氢溴化乙啶（DHE）荧光染色法测定细胞内活性氧（ROS）水平。RT—PCR法检测NOX2、小G蛋白（Racl）mRNA表达。Westernblot法检测NOX2、p47phox的表达。结果与正常对照组比较，DEX作用于PCI2细胞24h后，DEX（5、10μmol／L）组细胞活力下降、ROS水平显著增高。进一步研究显示DEX（5、10μmol／L）组可以上调NOX2和RaclmRNA的表达，可以增加NOX2、p47phox的表达。结论DEX可以增加PCI2细胞ROS的生成，诱导PCI2细胞氧化应激损伤，其机制可能与增加NOX2表达有关。

英文摘要：

Objective To investigate dexamethasone （DEX） induced PC12 cell death by oxidative stress and its influence on the NOX2 expression. Methods PC12 cells were randomly divided into five groups：control group, H202 （100 p, mol/L） group, DEX（ 1,5,10 p, mol/L）. The survival of PC12 cells was detected by MTI＂ assay. Intra- cellular reactive oxygen species （ROS） was assessed by dihydroethidium （DHE）, NOX2 and small G protein （ Racl ） mRNA level in PC12 cells were detected by RT-PCR. The expression of NOX2, p47phox was examined by Western blot. Results Compared with control group, the survival of PC12 cells in DEX （5, l0 ptmol/L） groups decreased and ROS level increased significantly after 24 h treatment. Furthermore, DEX could upgrade the expres- sions of NOX2 ,Rael mRNA and NOX2, p47phox. Conclusion DEX could increase the generation of intracellular ROS in PC12 cells and induce oxidative stress injury, NOX2. and its mechanism is possibly increased by the expression of NOX2.