脂多糖对体外培养人脐静脉内皮细胞分泌功能及活力的影响

目的：观察脂多糖对人脐静脉内皮细胞分泌缩血管因子内皮素-1、舒血管因子一氧化氮及其细胞活力的影响,为探讨感染性休克的发病机制提供实验资料。方法：选用体外培养的3代人脐静脉内皮细胞,分别使用浓度为1 g/L、100 mg/L、10 mg/L、1 mg/L、100 μg/L、10 μg/L、1 μg/L的脂多糖与之孵育6 h。分别使用放免法、硝酸还原酶法以及MTT法测定培养上清液内内皮素、一氧化氮的含量和内皮细胞的活力。结果：正常对照组培养基中ET-1的浓度(pg/L)为:251.64±10.90。脂多糖与内皮细胞共孵育组培养基中ET-1的浓度（pg/L）分别为：220.85±19.14、278.67±15.45、306.40±11.60、312.87±33.50、324.38±17.02、291.49±14.30、282.11±13.38，各组与正常对照组比较，P<0.05或P<0.01；正常对照组培养基中总硝酸根离子（NO_x）的浓度（μmol/L）为629.46±13.36，脂多糖与内皮细胞共孵育组培养基中NO_x的浓度(μmol/L)分别为：732.58±23.21、669.87±9.32、661.24±16.80、650.33±13.24、606.59±12.94、626.75±9.83、627.61±5.61，各组与正常对照组比较，P<0.05或P<0.01。各组内皮细胞的活力分别为：74%、81%、86%、88%、91%、93%、93%。结论：低浓度的脂多糖对血管内皮细胞不具有强烈的毒性作用，而主要以影响其功能为主：促进缩血管物质ET的分泌，而抑制舒血管物质NO的产生。而高浓度的LPS对血管内皮细胞不但有较强烈的毒性作用，同时影响其功能：抑制缩血管物质ET的分泌，而促进舒血管物质NO的产生。

Effect of lipopolysaccharide on viability and secretion function of human umbilical vein endothelial cells

AIM: To observe the direct effect of lipopolysaccharide (LPS) on secretion of endothelin-1 (ET-1) and nitric oxide by human umbilical vein endothelial cell and cell viability of the secretor. METHODS: The third passage of human umbilical vein endothelial cells were incubated with different concentrations of LPS (1 g/L, 100 mg/L, 10 mg/L, 1 mg/L, 100 μg/L, 10 μg/L, 1 μg/L) for 6 hours, and the culture supernatants were collected. The concentrations of ET-1 were determined by radioimmunoassay, the concentrations of nitric oxide were determined using Greiss's method. The viabilities of cells were measured by MTT method. RESULTS: The concentration of ET-1 (pg/L) of normal control group was 251.64±10.90. The concentrations of ET-1 (pg/L) of LPS treated groups were 220.85±19.14, 278.67±15.45, 306.40±11.60, 312.87±33.50, 324.38±17.02, 291.49±14.30, 282.11±13.38, respectively (each group compared with normal control group, P<0.05 or P<0.01). The concentration of NO_x (μmol/L) of normal control group was 629.46±13.36. The concentrations of NO_x (μmol/L) of LPS treated groups were 732.58±23.21, 669.87±9.32, 661.24±16.80, 650.33±13.24, 606.59±12.94, 626.75±9.83, 627.61±5.61, respectively (each group compared with normal control group, P<0.05 or P<0.01). The viabilities of endothelial cells of LPS treated groups were 74%, 81%, 86%, 88%,91%, 93%, 93%, respectively. CONCLUSION: LPS of lower concentrations had no significantly lethal effect on human umbilical vein endothelial cells, but enhanced secretion of ET-1 and inhibited NO production. LPS in higher concentrations showed significant lethal effect on human umbilical vein endothelial cells, inhibited secretion of ET-1 and enhanced NO production.