同型半胱氨酸对人脐静脉内皮细胞一氧化氮合酶基因表达的影响

Effects of homocysteine on the expression of endothelial nitric oxide synthase in cultured human umbical vein endothelial cell

目的:研究同型半胱氨酸(homocysteine,Hcy)对培养的人脐静脉内皮细胞(HUVEC)一氧化氮合酶(eNOS)基因表达的影响。方法:采用反转录聚合酶链反应(RT-PCR)和免疫组织化学方法,检测不同浓度Hcy(10μmol.L-1、30μmol.L-1、100μmol.L-1和300μmol.L-1)与HUVEC共同培养后,细胞内eNOSmRNA和蛋白表达、eNOS活性和一氧化氮(NO)生成的变化。结果:HUVEC经不同浓度Hcy处理24h后,其细胞内eNOS蛋白表达减少,活力降低,NO生成抑制。但只有100μmol.L-1Hcy与HUVEC作用72h时,才引起eNOSmRNA表达的减少。结论:提示Hcy可能通过抑制eNOS转录、蛋白表达及eNOS活力减少内皮源性NO的生成。

Objeetive： To study the effects of homocysteine （Hcy） at different concentrations on the expression of endothelial nitric oxide synthase（eNOS） mRNA and protein in cultured human umbical vein endothelial cell （HUVEC）. Methods：RT-PCR and immunohistoehemistry were performed to detect the expression of eNOS mRNA and eNOS protein, and the change of eNOS activity and NO biosynthesis after HUVEC were co-cultured with Hcy in different concentrations（10μmol·L^-1, 30μmol·L^-1 , 100μmol·L^-1 and 300μmol·L^-1） for 24 hours. Results ：After HUVEC were treated by different concentrations of Hcy for 24 hours, the eNOS protein expression decreased, and eNOS activity were inhibited, and the content of NO in culture medium was significantly reduced compared with the control group, but only when 100μmol·L^-1 Hey treated HUVEC for 72 h, RT-PCR products showed that the expression of eNOS mRNA decreased. Conclusion . Hcy can reduced the biosynthesis of NO from cultured HUVEC by inhibiting the expression of eNOS mRNA and protein, and eNOS activity.