槲皮素对过氧化氢诱导的血管内皮细胞周期及NO水平的影响

目的研究槲皮素对人脐静脉血管内皮细胞增殖周期及细胞内一氧化氮产生的影响。方法用过氧化氢诱导血管内皮细胞损伤，采用ＭＴＴ比色法、流式细胞仪观察槲皮素对血管内皮细胞作用及周期的影响；用硝酸还原酶法测定细胞培养液中ＮＯ水平。结果过氧化氢对血管内皮细胞具有损伤作用，槲皮素剂量依赖性促进过氧化氢诱导血管内皮细胞的增殖，而且主要是Ｓ期和Ｇ２Ｍ期细胞比率增加；槲皮素可减少过氧化氢诱导的血管内皮细胞释放乳酸脱氢酶及促进过氧化氢诱导血管内皮细胞内ＮＯ水平的增加。结论槲皮素可保护过氧化氢诱导血管内皮细胞的损伤及修复，其作用可能与ＮＯ的水平有关。

Effect of quercetin on cell cycle and nitroxide in hydrogenperoxide- induced of endothelial cells

AIM To study the effects of quercetin (Que) on cell cycle and nitric oxide in H2O2-induced the human umbilical vein endothelial cell line(ECV- 304). METHODS The experiment were performed in culture of H2O2-induced human umbilical vein endothelial cell line(ECV-304) in vitro. Cell viability was assessed by MTT assay and cell cycle was observed by flow cytometry. Nitroxide(NO) of ECV304 was monitored as No2- with colorimetry. RESULTS H2O2 inhabited the ECV-304 prolifteration. Preincubation of ECV-304 with one for 24 h before H2O2 exposure significantly increased the Cell viability and S-phase and G2M-phase cells. one reduced lactate dehydrogenase(LDH) and increased the level of nitric oxide in H2O2-induced ECV-304. CONCLUSION These results demonstrate that one can produce the protective action on H2O2-induced cultured ECV-304 and its effect of action may be related to level of nitric oxide.