依普利酮部分逆转甲状腺激素诱导的心肌电重构

Eplerenone partly reverses thyroid hormone induced myocardial electrical remodeling

目的:研究醛固酮拮抗剂依普利酮对甲状腺激素(T3)诱导的心肌电重构的影响。方法:原代培养SD乳鼠心肌细胞,并随机分为对照组、T3组、依普利酮(Epl)组、T3+Epl组采用免疫荧光法鉴定心肌细胞,CCK-8法检测T3与依普利酮对心肌细胞存活率的影响,细胞免疫荧光法、real-time PCR法、Western blot法检测各组钾离子通道Kv1.5、Kv4.3,L型钙离子通道Cav1.2缝隙连接蛋白40(Cx40)和Cx43 mRNA与蛋白的表达。结果:免疫荧光法显示所培养细胞为心肌细胞且95%以上横纹肌α-辅肌动蛋白(sarcomericα-actinin,α-actinin)抗体染色阳性。与对照组比较,T3增加Kv1.5、Kv4.3、Cav1.2与Cx40 mRNA与蛋白的表达,减少Cx43 mRNA与蛋白的表达;Ep1组Kv1.5、Kv4.3、Cav1.2与Cx40 mRNA与蛋白的表达降低,Cx43的表达升高;与T3组比较,T3+Epl组Kv1.5、Kv4.3、Cav1.2与Cx40 mRNA与蛋白的表达降低,Cx43的表达升高。结论:依普利酮可部分逆转甲状腺激素导致的心肌电重构。

AIM：To investigate the effects of eplerenone （Epl） on thyroid hormone （T3） induced myocardial electrical remodeling .METHODS：The ventricles of 1~3 d neonatal rats were digested with 0.125%trypsin and 0.08%collagenase type 2.The cell suspension was replated for 90 min to reduce the proportion of non-myocardial cells.The isola-ted cardiomyocytes were randomly divided into control group , T3 group, Epl group and T3＋Epl group.The cardiomyocytes were identified by immunofluorescence staining .The viability of the cardiomyocytes was measured by CCK-8 assay.The ex-pression of Kv1.5, Kv4.3, Cav1.2, connexin 40 （Cx40） and Cx43 at mRNA and protein levels was determined by immu-nofluorescence staining , real-time PCR and Western blot .RESULTS：The results of the cell immunofluorescence labeling conformed that the cultured cells were cardiomyocytes with more than 95%positive staining of sarcomeric α-actinin.Com-pared with control group , the mRNA and protein levels of Kv1.5, Kv4.3, Cav1.2 and Cx40 were increased, but the ex-pression of Cx43 was decreased in T3 group.The mRNA and protein levels of Kv1.5, Kv4.3, Cav1.2 and Cx40 were de-creased, but the expression of Cx43 was increased in Eplerenone group .Compared with T3 group, the mRNA and protein expression levels of Kv1.5, Kv4.3, Cav1.2 and Cx40 were decreased, but the expression of Cx43 was increased in T3＋Epl group.CONCLUSION：Eplerenone partly reverses T3-induced myocardial electrical remodeling .