中文摘要：

目的：研究P38α对人血管内皮细胞一氧化氮合酶（eNOS）基因启动子转录活性的影响。方法：利用硝酸还原酶法检测不同浓度氯化钴作用下人脐静脉血管内皮细胞-12（HUVEC-12）上清中的一氧化氮（NO）的含量。以pRL-TK为内参照，将已经构建好的pGL2-eNOS-p质粒分别与pGL3-BASIC、pcDNA3、p38α、及p38α（AF）共转染HUVEC-12细胞，利用双荧光素酶报告基因技术检测eNOS基因启动子转录活性，并在共转染的基础上加氯化钴刺激，并检测eNOS基因启动子转录活性。结果：氯化钴刺激下HUVEC-12细胞培养上清的NO含量随氯化钴作用浓度增加而提高，成功建立化学缺氧模型；p38α在正常和缺氧条件下均明显降低eNOS基因启动子的活性，可被无活性诱变体p38α（AF）逆转。结论：P38α下调人血eNOS基因启动子转录活性。

英文摘要：

Aim：To study the effect of the p38 MAPK signaling pathway on the regulation of endothelial nitric oxide synthase（eNOS） promoter activity. Methods： The nitric oxide（NO） from the supernatant of the ceils treated with different concentrations of cobaltous chloride was measured through nitric reducetase method. The cells were cotransfected with a pGL2-eNOS-p plus pGL3-BASIC, pcDNA3, p38α or negative mutant p38α（AF）, respectively, and a pRL-TK vector was used as an internal control. The transcription activity of human eNOS promoter was determined through using a double luciferase reporter gene system. Moreover, the cotransfected ceils were stimulated with the different concentrations of cobaltous chloride and the transcription activity of human eNOS promoter was measured by the same system. Results： As the concentration of cobaltous chloride increased, the NO was also increased, suggesting that chemical hypoxia model is successfully established. The p38α markedly downregulated the promoter activty under either hypoxia or standard condition, which could be reversed by its negative mutant p38α （AF）. Conclusion：The activation of the p38α MAPK signaling pathway downregulates the human eNOS promoter activity.