急性心肌缺氧对乳鼠心肌细胞脑钠尿肽表达的影响及其作用机制  

Effect of acute hypoxia on expression of brain natriuretic peptide in neonatal rat cardiomyocytes

作　　者：夏文静[1] 黄艺仪[2] 何建桂[1] 陈艺莉[1] 

机构地区：[1]中山大学附属第一医院心内科,广东广州510080 [2]中山大学附属第一医院急诊科,广东广州510080

出　　处：《中国病理生理杂志》2012年第5期852-857,共6页Chinese Journal of Pathophysiology

基　　金：广东省科学技术厅科研项目(No.2010B031600065)

摘　　要：目的:观察急性缺氧损伤对乳鼠心肌细胞脑钠尿肽(BNP)表达水平的影响并探讨其可能作用机制。方法:原代乳鼠心肌细胞缺氧、无糖、无血清培养以模拟心肌缺血损伤,利用CCK-8法测细胞存活率、ELISA法测白细胞介素-6(IL-6)和BNP的表达;以IL-6直接干预体外培养的心肌细胞,采用RT-PCR、Western blot-ting和ELISA方法观察BNP、转化生长因子β1(TGF-β1)、Smad2 mRNA的转录和蛋白的表达。结果:缺氧显著上调IL-6和BNP的表达,且两者呈线性正相关;IL-6直接干预可剂量和时间依赖性地上调心肌细胞BNP的mRNA和蛋白表达水平,同时TGF-β1和Smad2的表达水平亦增加;而针对TGF-β1的中和抗体能够部分地抑制由IL-6引起的BNP表达增加。结论:急性心肌缺氧可直接上调BNP的表达水平,这种调节效应与TGF-β1/Smad2信号通路上调有关。AIM： To explore the influence of acute myocardial hypoxia on the expression of brain natriuretic peptide （BNP） in neonatal rat cardiomyocytes. METHODS： To establish a model of simulated hypoxia injury, the prima- rily cultured neonatal rat cardiomyocytes were incubated under the condition of hypoxia in glucose - free balanced salt solu- tion plus serum deprivation. The cell survival rate was analyzed by Cell Counting Kit - 8 （ CCK - 8 ） and the levels of inter- leukin - 6 （ IL - 6 ） and BNP were determined by enzyme - linked immunosorbent assay （ELISA）. The transcriptional and translational levels of BNP, transforming growth factor β1 （TGF - β1 ） and Smad2 in cardiomyocytes with IL -6 stimulation were determined by RT- PCR, Western blotting and ELISA. RESULTS： Exposure of the neonatal cardiomyocytes to an oxygen -deficient environment notably increased IL -6 and BNP secretion, and BNP expression was positively correlated with IL - 6 expression. Stimulation of the neonatal cardiomyocytes with IL - 6 caused time - and dose - dependent up - regulation of transcriptional and translational levels of BNP. This process was accompanied with the up - regulation of TGF -β1/Smad2. Inhibition of TGF- β1 activity using a neutralizing antibody partially suppressed the IL -6 -stimulated in- crease in BNP expression. CONCLUSION： Acute myocardial hypoxia directly up - regulates the expression of BNP, which is associated with the up- regulation of TGF- β1/Smad2 signal pathway.

关 键 词：缺氧 钠尿肽 脑 白细胞介素-6 转化生长因子Β Smad2通路 

分 类 号：R541.4[医药卫生—心血管疾病]