中文摘要：

背景：近几年有关mas基因与心血管疾病的关系成为研究的热点，但有关血管紧张素（1～7）mas轴在调节心血管功能及在心血管疾病发病过程中发挥作用的信号转导途径还不甚清楚。目的：实验拟构建血管紧张素（1～7）受体mas稳定转染细胞株及mas基因表达和活化对ERKMAPK信号通路的影响。设计、时间及地点：重复测量设计，实验于2006-07／2008-03在首都医科大学生物化学与分子生物学实验室完成。材料：人mas全长cDNA，原核表达载体pEGFPC2，菌株E．coli DH5α，COS-7细胞均由s本实验室保存。方法：将mas cDNA克隆到真核表达载体pEGFPC2中，构建重组质粒pEGFP-mas。再将重组质粒转染COS-7细胞，筛选稳定表达细胞株。主要观察指标：经血管紧张素（1～7）刺激后，检测稳定转染mas的COS-7细胞中ERK磷酸化水平变化。结果：与对照组相比，稳定转染mas的COS-7细胞经血管紧张素（1～7）刺激后，ERK磷酸化水平显著升高（P〈0．05）。p-ERK水平在10min内达到最高值，并且随着血管紧张素（1～7）浓度的增加（10^12～10^-6 mol／L），p-ERK水平逐渐升高。结论：成功构建mas稳定表达细胞模型，并显示出血管紧张素（1～7）受体mas活化可以引起下游ERK1／2信号通路的激活。

英文摘要：

BACKGROUND： In recent years, the correlation between mas gene and cardiovascular disease has become a study focus. However, the mechanism of angiotensin-（1-7）-mas axis in regulating cardiovascular function and the role in progression of cardiovascular disease are still unknown. OBJECTIVE： To construct cell lines transfected by angiotensin-（1-7） receptor, and observe the gene expression of mas, and the effect of activated mas on extracellular signal-regulated kinase （ERK）. DESIGN, TIME AND SETTING： The repetitive measurements were performed at the Laboratory of Biochemistry and Molecular Biology, Capital Medical University from July 2006 to March 2008. MATERIALS： Plasmid and bacterium included human mas cDNA, pEGFP-C2 vector, E. coli DH5α, and COS-7 cell line. METHODS： mas cDNA was cloned into pEGFP C2 vector, and the recombinant plasmid pEGFP-mas was transfected in COS-7 cell lines. The cell lines with stable expression were screened by G418. MAIN OUTCOME MEASURES： Phosphorylated ERK level in COS-7 cell lines was examined following stimulation with angiotensin-（1-7）. RESULTS： Compared with control group, phosphorylated ERK level increased significantly after stimulation with angiotensin-（1-7） （P 〈 0.05）. Peak value of p-ERK level was found within 10 minutes and p-ERK level increased with the increasing of angiotensin-（1-7） （10^12-10^6 mol/L）. CONCLUSION： The cell lines with stable expression are successfully constructed. ERK signaling is activated by angiotensin-（1-7） through mas.