氧化低密度脂蛋白对内皮细胞L-精氨酸-NO系统的影响及其机制

目的　探讨氧化低密度脂蛋白 (ox LDL)对内皮L 精氨酸 NO系统的影响及其机制。方法　生化分析方法测定孵育液中亚硝酸盐含量及一氧化氮合酶活性 ,用Western印迹方法测定内皮一氧化氮合酶 (eNOS)的蛋白表达。结果　不同浓度的ox LDL呈剂量依赖性地降低eNOS的蛋白表达 ,抑制NOS活性及内皮产生的NO量 (11.4 4± 1.4 3vs 8.18± 1.0 ,6 .4 5± 0 .99,5 .83± 0 .95 ,P <0 .0 5 ) ,(1.94± 0 .12vs 1.73± 0 .14 ,1.5 7± 0 .11,1.4 6± 0 .12 ,P <0 .0 5 ) ,预先加入血凝素样氧化低密度脂蛋白受体 (LOX1)抑制剂阻断了ox LDL的上述作用。结论　ox LDL损伤内皮细胞 ,导致内皮L 精氨酸 NO系统的改变 ,LOX1介导了ox LDL的这一作用

Exploration of the effect of oxidized-LDL on L-Arg-NO system of endothelial cells and its mechanism

Objective To explore the effect of oxidized LDL (ox LDL) on L Arg NO system of endothelial cells and its mechanism.Methods The nitrite content of the culture medium and the activity of endothelial NO synthase(eNOS) were measured with biochemical method.The protein expression of eNOS was examined with Western Blot.Results NO production,the activity of NOS and the protein expression of eNOS in endothelium were decreased in dose dependent manner after incubation with ox LDL 25,50,100 mg/L[(1.94±[CM)] 0.12 vs.1.73±0.14,1.57±0.11,1.46±0.12,P<0.05),(11.44±1.43 vs 8.18±1.0,6.45±0.99,5.83±0.95,P<0.05)].The inhibitor of lectin like oxidized LDL receptor(LOX1) inhibited the effect of ox LDL on endothelial L Arg NO system..The inhibitor of lectin like oxidized LDL receptor(LOX1) inhibited the effect of ox LDL on endothelial L Arg NO system.Conclusion Ox LDL impaired endothelial L Arg NO system,and LOX1 mediated the injurious effect of ox LDL on endothelial cells.