辛伐他汀对血管内皮细胞分泌NO的影响

Effect of simvastatin on NO secreted by endothelial cells

目的观察辛伐他汀对血管内皮细胞分泌NO的影响。方法培养的血管内皮细胞加入不同浓度的辛伐他汀(1×10-7mmol/L、1×10-6mmol/L、1×10-5mmol/L),孵育24h后,采用重氮化反应法测培养液上清中亚硝酸盐的含量;取辛伐他汀1×10-5mmol/L浓度,分别在6、12、24、48h测培养液上清中的亚硝酸盐含量;取辛伐他汀1×10-5mmol/L浓度,分别加入L-甲基精氨酸1×10-3mol/L、甲羟戊酸1×10-4mol/L、角鲨烯1×10-5mol/L、牻牛儿基牻牛儿醇焦磷酸15μmol/L,培养24h,测培养液上清中的亚硝酸盐含量。结果3种不同浓度比对照组分别增加2.15、2.22和3.66倍;药物作用时间为12、24、36h时,较对照组分别增加0.68、3.66和5.20倍,随着给药浓度的增加和药物作用时间的延长,辛伐他汀对血管内皮细胞分泌NO的促进作用逐渐增强,与对照组比较差异有统计学意义。辛伐他汀对血管内皮细胞分泌NO的促进作用能被L-甲基精氨酸、甲羟戊酸、牻牛儿基牻牛儿醇焦磷酸逆转,而不被角鲨烯逆转。结论辛伐他汀呈时间剂量依赖性促进血管内皮细胞分泌NO,这种作用与其降脂作用无关,而与其抑制类异戊二烯物质的合成有关。

Objective To investigate the effect of simvastatin on NO secreted by endothelial cells. Methods Primary culture of the vascular endothelial cells were obtained from the human umbilical vein. Simvastatin in different concentration（from 1×10^-7 mmol/L to 1×10^-5 mmol/L） were added to the medium. After 24 h,supernatant of the medium were collected and NO levels in culture medium were determined eolorime trically. NO levels in culture media with simvastatin （1×10^-5 mmol/L） were also respectively determined by the same methode after 6 h, 12 h,24 h,48 h. We incubated vascular endothelial cells respectively with NG-minomethyl-L-arginine （ L-NMMA ）, mevalonate, squalene, farnesylpyrophosphate （ FFP ） and geranylgeranyl -pyrophosphate （ GGPP ） in the prensenee of simvastatin （1×10^-5 mmol/L） .After 24 h,supernatant of the medium were collected and NO levels in culture medium were determined eolorime trieally. Results Simvastatin promoted the secretion of NO in a timedisc-dependent manner. L-NMMA, mevalonate and GGPP completely blocked the stimulatory effects of simvastatin （1×10^-5 mmol/L） on nitrite production after a 24-hour incubation period. Squalene and FPP did not.Conclusion Simvastatin improve the function of vascular endothelial cells and the effect of simvastatin is independent from its lipid lowering properties.