机械压力对人脐静脉内皮细胞ET-1、NO合成的影响和意义  

Effect of mechanical pressure on the synthesis of ET-1 and NO in cultured human umbilical vein endothelial cells and implication

作　　者：张彤[1] 杨镇[1] 

机构地区：[1]华中科技大学同济医学院附属同济医院普外科

出　　处：《临床外科杂志》2006年第7期417-419,共3页Journal of Clinical Surgery

基　　金：国家自然科学基金资助项目(30170920)

摘　　要：目的探讨压力增高对血管内皮细胞分泌血管活性物质功能的影响及其在门静脉高压症发病机制中的作用。方法用RT-PCR方法半定量研究人脐静脉内皮细胞ET-1、eNOS、i-NOS mRNA的表达;用硝酸还原酶法检测各组细胞培养液中NO代谢产物NO2-/NO3-的含量,免疫荧光标记激光扫描共聚焦显微镜检测培养细胞的ET-1蛋白表达。结果ET-1和eNOS mR-NA在正常培养的内皮细胞中即有表达,iNOS mRNA则几乎无表达。生理水平压力刺激下各组各待测基因mRNA表达与对照组无显著性差异。超生理范围压力刺激后,ET-1 mRNA有显著性升高。eNOS mRNA在40 mm Hg 24 h后才有显著性差异。iNOS mRNA在不同条件下均无显著变化。在细胞培养液中分别加入细胞外钙螯合剂EGTA、PKC抑制剂后,则见ET-1、eNOS mRNA表达下降。结论压力增高可刺激血管内皮细胞合成ET-1、NO,其作用在转录水平,其作用机制分别与PKC信号通路和细胞外钙浓度有关。门静脉压力增高与血管内皮细胞合成ET-1、NO增多之间存在相互作用。Obiective To investigate the influence of enhanced blood pressure on the function of secreting vasoactive substances by vascular endothelial cells, and its significance in the pathogenesis of portal hypertension. Methods The human umbilical vein endothelial cell line ECV304 was cultured in different conditions, and the expression of ET - 1, eNOS and iNOS mRNA was detected by using semi - quantitative RT - PCR, The concentrations of NO2^-/NO3^- in the media were determined by using nitrate reductase method. Furthermore, the method of immunofluorescence labeling combined with laser scanning confocal microscopy was used to detect the expression of ET - 1 protein in the cells. Results The expression of ET - 1 and eNOS mRNA was detected in the static cultured endothelial cells, and the expression of eNOS mRNA was slightly higher than ET - 1. However, the expression of iNOS mRNA was hardly detected. There was no significant difference in the groups treated with 15 mm Hg and the control group. ET- 1 mRNA was increased significantly after 2 h when the cells were cultured at 40 mm Hg, and it was increased more significantly after 24 h. eNOS mRNA was also increased at 40 mm Hg, but the differencewas not significant until 24 h. There were no any changes in the expression of iNOS mRNA at different pressure and time points. The upregulation of ET - 1 and eNOS mRNA caused by pressure could be inhibited by PKC inhibitor staurosporine or extracellular calcium chelator EGTA respectively. Conclusion Enhanced pressure can stimulate the synthesis of ET- 1 and NO in vascular endothelial cells. Ir acts on the gene expression at the level of transcription, and its action is related to the PKC signal transduction pathway or the concentrations of extracellular calcium respectively.

关 键 词：机械压力 血管内皮细胞 内皮素 一氧化氮 

分 类 号：R363[医药卫生—病理学]