TRPM7参与AngⅡ对心肌细胞镁离子平衡的调节  

TRPM7 is involved in Ang Ⅱ regulation of magnesium homeostasis in cardiomyocytes

作　　者：郭瑞娜[1] 李小青[1] 沈之君[1] 

机构地区：[1]南通大学医学院病理学与病理生理学系,江苏南通226001

出　　处：《东南大学学报（医学版）》2014年第4期445-449,共5页Journal of Southeast University(Medical Science Edition)

基　　金：江苏省基础医学优势学科建设基金资助项目

摘　　要：目的:探讨TRPM7在血管紧张素Ⅱ(AngⅡ)对心肌细胞镁离子平衡调节中的作用。方法:采用原代培养的小鼠心肌细胞作为研究对象,实验分对照、AngⅡ、AngⅡ+氯沙坦(Losartan,AngⅡ的Ⅰ型受体阻断剂)及AngⅡ+2-APB(TRPM7通道阻断剂)组。实验试剂直接加入培养液中与细胞共孵育,应用mag-fura-2镁离子荧光探针动态检测心肌细胞内镁离子水平的变化,实时定量PCR(qPCR)和Western Blotting检测TRPM7在原代培养心肌细胞中的表达水平。结果:与对照组相比,AngⅡ组心肌细胞胞内游离镁离子水平在细胞外生理镁离子浓度及高镁离子浓度环境下均有显著下降;应用Losartan或2-APB均可显著降低AngⅡ所致的游离镁离子下降的作用。qPCR和Western Blotting检测结果提示,AngⅡ对原代培养心肌细胞中TRPM7的表达水平无影响。结论:AngⅡ可通过Ⅰ型受体对原代培养心肌细胞的镁离子代谢产生显著影响,其机制可能是AngⅡ增强了心肌细胞TRPM7的功能而不影响其表达水平。Objective： eardiomyocytes regulated study. Cell cultures were The aim of this study is to investigate the role of TRPM7 in magnesium homeostasis in by Ang Ⅱ. Methods： Primary cultured mouse neonatal cardiomyocytes were used for this divided into control, AngⅡ, Ang Ⅱ ＋ Losartan and Ang Ⅱ ＋ 2- APB groups. Testing agents were added into culture median and coincubated with cells. Intracellular free magnesium levels were monitored with a magnesium selective fluorescent dye mag-fura-2. Real time quantitative PCR （qPCR） and Western Blotting were used for estimating the expression of TRPMT. Results：Comparing to the control group, intracellular magnesium levels was significantly decreased in Ang Ⅱ group when physiological and high magnesium were present in the extracellular solution. Both losartan or 2-APB significantly reduced the role of decrease of intracellular magnesium levels caused by Ang Ⅱ. Further studies with qPCR and Western Blotting indicated that the expression levels of TRPM7 were not affected by Ang Ⅱ in cultured cardiomyocytes. Conclusion： Ang Ⅱ significantly affected intracellular magnesium homeostasis in primary cultured cardiomyocytes via its AT1 receptor. The underlying mechanism is Ang Ⅱ can enhance the function of TRPM7 with no effects on expression.

关 键 词：心肌细胞 MG^2+ TRPM7 血管紧张素Ⅱ 

分 类 号：R36[医药卫生—病理学]