不同尿素氮水平尿毒血清对人脐静脉内皮细胞的影响

Effect of Different Blood Urea Nitrogen Level Uremic Serum on Human Umbilical Vein Endothelial Cells

目的:观察不同BUN水平尿毒血清对体外培养人脐静脉内皮细胞(HUVEC)的影响,并探讨尿毒症患者动脉粥样硬化发病的可能机制。方法:比色法测定HUVEC上清液NO、MDA的水平;免疫细胞化学法测定胞浆iNOS表达;酶联免疫吸附法(ELISA)测定上清液iNOS蛋白水平。结果:尿毒血清各组均可上调HUVEC的MDA生成,且以BUN≥50mmol/L的尿毒血清组对MDA上调最明显(P<0.01);尿毒血清各组可下调HUVEC的NO生成,呈BUN浓度依赖性关系(P<0.01);尿毒血清各组可激活HUVEC的iNOS,诱导细胞生成大量NO,但随着BUN水平的升高,NO、iNOS呈下降趋势,BUN≥50mmol/L尿毒血清组下降显著(P<0.01)。结论:尿毒血清对HUVEC有毒性作用,呈BUN浓度依赖性关系,尤其是BUN≥50mmol/L时,细胞损伤更为加重。

Objective： To observe the effect of different blood urea nitrogen （BUN） level uremic serum on human umbilical vein endothelial cells （HUVEC） cultured in vitro, and investigate the possible mechanism about atherosclerosis in uremia patients. Methods： The content of NO and MDA were detected by colorimetry, and the expression ofiNOS was detected by immunocytochemical staining in HUVEC cytoplasm. The protein expression of iNOS in supemate was detected by enzyme-linked immunosorbent assay （ELISA）. Results： The MDA capacity with uremic serum in HUVEC was significantly higher than that of control group, and the group of BUN≥ 50 mmol/L uremic serum showed the greatest upregulation （P〈0.01）. The level of NO in uremic serum media was significantly lower than that of the control, with a BUN concentration-dependence （P〈0.01）. The expression ofiNOS in HUVEC was activated by uremic serum and induced a lot of NO. However, with BUN level increased, the level of NO and iNOS were decreased, with the most significant decrease in group of BUN ≥50 mmol/L uremic serum （P〈0.01）. Conclusion： Uremic serum can impair HUVEC in a BUN concentration-dependent manner, and BUN ≥ 50 mmol/L uremic serum showed the worst effect.