替米沙坦抑制钙调神经磷酸酶调控牵张刺激诱导乳鼠心房肌细胞Cav1.2mRNA的表达  

Telmisartan prevents stretch-induced Cav1.2 mRNA expression in cultured atrial neonatal myocytes via calcineurin signal

作　　者：杨龙[1] 何炯红[1] 袁正强[1] 徐敏[1] 李杰[1] 柏小川[1] 刘丹[1] 关婧[1] 

机构地区：[1]遵义医学院第三附属医院,563003

出　　处：《贵州医药》2011年第9期771-775,共5页Guizhou Medical Journal

基　　金：国家自然科学基金资助[项目批准号81060018]

摘　　要：目的探究牵张刺激对乳鼠心房肌细胞L型钙离子通道(Ca-L)Cav 1.2 mRNA表达的影响以及替米沙坦(Tel)的调控作用。方法 1 d龄SD乳鼠,分离心房肌细胞,于细胞牵引装置培养24 h分组干预:(1)对照组:不予牵张刺激;(2)牵张组:牵张增加16%硅胶膜面积48 h;(3)Tel组:予Tel 1μmol/L干预1 h,继之牵张48 h;(4)环孢素A(CsA)组:CsA 10μg/mL干预1 h,继之牵张48 h。定量分析牵张组与对照组细胞蛋白/DNA比值,行牵张有效性鉴定。免疫印迹法检测钙调神经磷酸酶A亚基(CaNA)表达;适时荧光定量逆转录PCR检测Cav 1.2 mRNA表达。结果牵张刺激明显增加心房肌细胞蛋白/DNA比值,促CaNA蛋白表达,抑制Cav 1.2 mRNA表达;Tel和CsA干预明显抑制牵张刺激此效应。结论替米沙坦可通过抑制钙调神经磷酸酶进而调控静态牵张刺激诱导的心房肌细胞Cav 1.2 mRNA表达。Objective Used a model of cultured atrial neonatal rat cardiomyocytes under conditions of stretch to provide the role of telmisartan on the Cav1. 2 mRNA expression in stretched atrial myocytes of neonatal rats. Methods Atrial cardiomyocytes of neonatal rats cultured on the silicone sheeting were stretched for 48 hours with or without pre-treated with telmisartan or cyclosporine, samples without stretched were regarded as the control. Calcineurin A subunit （CaNA） protein in cell extracts was assayed by western blot analysis. The expression of Cavl. 2 gene （encoding for alpha 1C subunit of L-type calcium ion channel） was assayed by real-time reverse transcriptase-polymerase chain reaction （RT-PCR） analysis. ResultsStretch significantly increased protein-to-DNA ratio, indicating hypertrophy, and the expression of CaNA protein. Expression of Cavl. 2 gene was significantly reduced in stretched myocytes. Telmisartan （1 μM） or cyclosporine （10μg/ml） prevented stretch--induced increases in the protein-to-DNA ratio and the expression of CaNA protein in stretched myocytes. Concomitantly, telmisartan or cyclosporine attenuated stretch--induced alteration in Carl. 2 mRNA expression. Conclusion Telmisartan prevents the down-regulation of stretch--induced Carl. 2 mRNA expression enrolled the calcineurin signal.

关 键 词：牵张 离子通道 血管紧张素受体阻断剂 钙调神经磷酸酶 

分 类 号：R542.2[医药卫生—心血管疾病]