氧化修饰LDL对培养人脐静脉内皮细胞DNA合成和胆固醇酯合成的影响

Effects of Oxidized LDL on DNA Synthesis and Cholesterol Ester Synthesis in Cultured Human Umbilical Vein Endothelial Cells

研究氧化低密度脂蛋白（ｏｘＬＤＬ）对内皮细胞的损伤作用。方法：以胸腺嘧啶核苷（３Ｈ－ＴｄＲ）掺入法和胆固醇酯薄层层析法，观察ｏｘＬＤＬ对培养的人脐静脉内皮细胞（ＨＵＶＥＣ）ＤＮＡ合成和胆固醇酯含量的影响。结果：ｏｘＬＤＬ抑制内皮细胞ＤＮＡ合成，并与浓度及作用时间相关，１００ｍｇ·Ｌ－１的ｏｘＬＤＬ作用２４ｈ的内皮细胞掺入３Ｈ－ＴｄＲ的ｄｐｍ数为不加ＬＤＬ组的４８％（Ｐ＜０．００１），天然ＬＤＬ（ｎＬＤＬ）对ＨＵＶＥＣ掺入３Ｈ－ＴｄＲ也有轻度的抑制作用。ｏｘＬＤＬ降低ＨＵＶＥＣ内胆固醇酯的含量，５０ｍｇ·Ｌ－１ｏｘＬＤＬ孵育的ＨＵＶＥＣ胞内胆固醇酯含量是ｎＬＤＬ组的４２％。扫描电镜发现ｏｘＬＤＬ孵育的ＨＵＶＥＣ形态发生改变，胞间连接减少。结论：ｏｘＬＤＬ对ＨＵＶＥＣ具有细胞毒作用，促发动脉粥样硬化。

bjective:To investigate the injurious effects of oxidized low density lipoprotein on endothelial cells.Method:The effects of oxLDL on DNA synthesis in HUEVC and the intracellular content of cholesterol ester were investigated with the help of 3HTdR incorporation and thinlayer chromatography.Results:The results indicated that the oxLDL inhibited the incorporation of 3HTdR into HUVEC in time and dosedependant manners.At the end of 24hour incubation at concentration of 100mg·L -1 ,the dpm for 3HTdR incorporated into the cells in oxLDL group was 48% as that of controls( P <0.001).The native LDL inhibited the DNA sythesis mildly.It was found that the cholesterol ester mass was 42% in the oxLDL group as that of nLDL's at 50mg·L -1 for 20h.The scanning electron microscopy showed that the intercellular junctions diminished and the cellular outline changed in cells treated with oxLDL.Conclusion:OxLDL has a cytotoxic effect on the HUVEC and contributes to the atherogenesis.