孕激素对兔血管平滑肌细胞AT_1受体基因表达的作用差异及机制分析  

Effects of Progesterone on AT_1 Receptor Gene Expression in Vascular Smooth Muscle Cell and Its Molecular Mechanisms.

作　　者：尚美生 乔中东 吕吉元 赵荣瑞 

机构地区：[1]山西省医科大学第一医院

出　　处：《中西医结合心脑血管病杂志》2005年第11期977-980,共4页Chinese Journal of Integrative Medicine on Cardio-Cerebrovascular Disease

摘　　要：目的通过观察孕激素对培养血管平滑肌细胞(VSMCs)AT1R mRNA表达的影响,并寻求探索其潜在的分子机制,为临床干预提供实验依据。方法分别用孕激素及其特异性受体拮抗剂对培养的血管平滑肌细胞行不同时间、不同浓度的处理,然后用胰蛋白酶-EDTA消化,离心收集,提取总RNA,用RT-PCR对AT1R mRNA进行半定量分析,利用Western-blot对其相应的蛋白进行测定。结果孕酮对VSMCs AT1R的影响呈现明显的时间依赖性,12h达到最大值为156%±18%,表现为上调;并呈现浓度依赖性,当孕酮浓度是10-10M时对AT1R mRNA的上调影响达到最大为59.9%±4.2%;孕酮对AT1R mRNA蛋白的上调以12h为最大,达到最大值为8.44%±1.08%;孕酮受体拮抗剂0.1nM的米非司酮对VSMCs AT1RmRNA无影响,但米非司酮抵消了孕酮对VSMCs AT1R mRNA的上调作用,而孕酮引起的AT1R mRNA的上调只能被三磷酸肌醇(IP3)的抑制剂Wortmannin所抑制。结论孕酮对VSMCs AT1R mRNA表现为上调,其特征呈现时间和浓度依赖性,其最大上调作用发生于12h,最大作用的浓度为0.1nM,孕激素的作用机制可能是与其受体结合后激活了IP3激酶的第二信号系统。Objective To investigate the direct effects of progesterone on vascular cells, its influence on AT1 receptor mRNA expression in vascular smooth muscle cell（VSMCs） were examined to clarify the underlying molecular mechanisms, so as to offer the experimental evidence for clinical intervention. Methods To assess time - dependent and concentration - dependentmodulation progesterone on expression of AT1R mRNA in VSMCs, Co - incubation of VSMCs and progesterone were performed to evaluate the direct effect of this hormone on the cultured VSMCs. To assess whether this modulation of AT1R mRNA expression translates into comparable changes in AT1R mRNA protein levels, western analysis was used to quantify AT1R protein. Cells were prepared for total mRNA extraction. AT1R mRNA was measured by RT - PCR. Results Progesterone led to an upregulation of AT1R mRNA, reaching the maximum effect 156% ± 18% of control levels after 12 hours. After 12 - hour treatment, the increase was most pronounced at concentrations of progesterone （10 - 10M）, which led to an increase of AT1R mRNA to 59.9% ± 4.2% of control cells. Progesterone induced an upregulation 8.44 % ± 1.08 % of AT1R protein expression. Mifepristone exerted no effect on AT1R mRNA expression. Mifepristone could completely abolished the effect of progesterone. Progesterone caused AT1R upregulation was abolished on coineubation with Wortmannin. Conclusion Progesterone induced a upregulation of AT1R mRNA in VSMCs. Progesterone caused AT1 receptor overexpression via IP3 - kinase activation. The progesterone - caused AT1 receptor overexpression might in part explain the adverse influences of progesterone on the cardiovascular system.

关 键 词：动脉粥样硬化 平滑肌细胞 孕激素 AT1受体 

分 类 号：R543[医药卫生—心血管疾病]