【摘要】 目的:探讨内皮衍生微粒(EMP)诱导内皮功能失调的机制和氧自由基(O2.-)在EMP诱导内皮功能失调中所起的作用。方法:从人血纤维蛋白溶酶原激活抑制剂-1刺激的人脐静脉内皮细胞中提取EMP,(1)采用牛主动脉内皮细胞(BAEC)做细胞培养,分成3组。第1组不做预处理,第2组EMP(1×108/L),第3组EMP(1×108/L)+L-nitroarginiemethylester(L-NAME,1mmol/L),预处理BAEC30min后,用超氧化物歧化酶(SOD)可抑制的铁细胞色素C还原法,测量O.2-的产生情况。(2)从小鼠中分离面动脉,分成4组。第1组不做预处理,第2组EMP(1×108/L),第3组EMP(1×108/L)+SOD(2×105U/L),第4组EMP(1×108/L)+聚乙烯羟乙酸盐超氧化物歧化酶(PEG-SOD,2×105U/L)预处理血管10min后做乙酰胆碱(ACH)诱导下的内皮依赖血管舒张功能试验。结果:(1)EMP明显增加BAECO.2-产生,L-NAME可以抑制50%EMP导致的O.2-产生增加。(2)EMP明显损伤ACH诱导的血管舒张功能,SOD处理未能清除EMP对血管舒张功能的损伤,PEG-SOD可部分恢复EMP处理后的血管舒张功能。结论:EMP诱导血管内皮功能失调至少部分是通过诱导细胞内产生的O2.-所致,为将来寻找包括清除O.2-在内的综合治疗方法提供理论依据。更多还原

【Abstract】 AIM:To investigate the mechanism of endothelium-derived microparticles(EMP)-induced endothelial dysfunction and the role of superoxide anion(O-·2) in EMP-induced endothelial dysfunction.METHODS:EMP were isolated from human umbilical vein endothelial cells stimulated with plasminogen activated inhibitor-1.(1) Cultured bovine aortic endothelial cells(BAEC) were divided into 3 groups and pretreated with nothing in group 1,EMP(1×108/L) in group 2,EMP(1×108/L) + L-nitroarginiemethylester(L-NAME,1 mmol/L) in group 3 for 30 min and A23187(5 μmol/L) stimulated O-·2 generation was determined by superoxide dismutase(SOD)-inhibitable ferricytochrome C reduction.(2) Facialis arteries(60-150 microns) were isolated from C57BL/6 mice and divided into 4 groups.The vessels were pretreated with nothing in group 1,EMP(1×108/L) in group 2,EMP(1×108/L) + SOD(2×105 U/L) in group 3,EMP(1×108/L) + polyethylene glycolated-SOD(PEG-SOD,2×105 U/L) in group 4 for 10 min and acetylcholine(ACH)-induced vasodilation was measured.RESULTS:(1) EMP significantly increased O-·2 generation in BAEC culture,which was prevented about 50% by pretreating the BAEC with L-NAME.(2) EMP significantly impaired ACH-induced vasodilation.SOD could not restore EMP-impaired ACH-induced vasodilation and PEG-SOD showed partial restoration of vasodilation.CONCLUSION:These data indicate that at least some EMP-induced endothelial dysfunction occurs by inducing intracellular O-·2 generation.It may provide a theoretical evidences in finding a multiple treatment including removal of O-·2 in the future.更多还原