Na^+-K^+-ATPase活性降低在LPS诱导大鼠心肌细胞肥大中的作用  

Role of Na^+-K^+-ATPase in lipopolysaccharide-induced cardiomyocyte hypertrophy in rats

作　　者：王立群[1] 陈唐葶[1] 蔡颖谦[2] 薛翔[1] 周翔[1] 金春华[1] 

机构地区：[1]南方医科大学医学基础实验教学中心,广东广州510515 [2]南方医科大学珠江医院神经外科,广东广州510282

出　　处：《南方医科大学学报》2010年第9期2059-2062,共4页Journal of Southern Medical University

基　　金：国家自然科学基金(30570707)~~

摘　　要：目的应用原子力显微镜探索内毒素(LPS)诱导心肌细胞肥大的作用并对其机制进行初步探讨。方法实验分两部分:第一部分,原代培养新生鼠心肌细胞,加入LPS(100μg/L)分别刺激1、4和8h后,应用原子力显微镜(AFM)扫描心肌细胞并测定单个心肌细胞的二维面积、表面积和体积,同时测定心肌细胞总蛋白含量和Na+-K+-ATP酶的活性;第二部分,应用Na+-K+-ATP酶抑制剂哇巴因(0.5μmol/L)刺激心肌细胞8h后,测定单个心肌细胞的二维面积、表面积和体积,同时测定心肌细胞总蛋白含量。结果 (1)与正常对照组相比,LPS(100μg/L)作用8h后,单个心肌细胞二维面积、表面积、体积和总蛋白含量明显增大(P<0.05);(2)与正常对照组相比,LPS(100μg/L)作用4和8h后,心肌细胞Na+-K+-ATP酶活力均明显降低(P<0.05);(3)与正常对照组相比,哇巴因(0.5μmol/L)作用8h后单个心肌细胞的二维面积、三维表面积、体积以及总蛋白含量均明显增大(P<0.05)。结论 LPS可以诱导心肌细胞肥大,其机制可能与LPS引起的Na+-K+-ATP酶活性降低有关。Objective To explore the possible mechanism of lipopolysaccharide（LPS）-induced cardiomyocyte hypertrophy in rats.Methods Neonatal rat cardiomyocytes cultured in vitro were stimulated with 100 μg/L LPS for1,4 or8 h and scanned by atomic force microscopy（AFM） for measurement of the two-dimensional area,three-dimensional surface area and volume of each cell.The total proteins and Na＋-K＋-ATPase activity in the cardiomyocytes were determined.The same measurements were also carried out in neonatal rat cardiomyocyte cultures stimulated by 0.5 μmol/L ouabain for 8 h and the total protein levels were measured.Results Following a 8-hour stimulation with LPS,the two-dimensional area,three-dimensional surface area and volume of the single cardiomyocyte became enlarged and the total cellular proteins increased significantly as compared with those in the normal control cells（P〈0.05）.LPS treatment for 4 and 8 h resulted in significantly decreased activity of Na＋-K＋-ATPase in the cardiomyocytes（P〈0.05）.In the cells treated with ouabain for8 h,the two-dimensional area,three-dimensional surface area,volume of the single cardiomyocyte and the total cellular proteins increased significantly in comparison with the normal control group（P〈0.05）.Conclusion LPS can result in cardiomyocyte hypertrophy in rats possibly in relation to lowered Na＋-K＋-ATPase activity in the cardiomyocytes afterLPS exposure.

关 键 词：心肌细胞 原子力显微镜 脂多糖 NA+-K+-ATP酶 哇巴因 

分 类 号：R541[医药卫生—心血管疾病]