组织蛋白酶L在扩张型心肌病心肌中的表达及其意义

目的探讨溶酶体组织蛋白酶L在扩张型心肌病(DCM)心肌组织中的表达及其在DCM发病中的意义。方法终末期扩张型心肌病行心脏移植术的受体标本20例(心肌病组)及脑死亡3h内排除心脏疾患的心脏标本5例(对照组),通过免疫组化、Westernblotting和实时定量RTPCR等方法检测心肌组织组织蛋白酶L基因转录及蛋白表达水平,并对组织蛋白酶LmRNA表达水平的动态变化与射血分数进行相关性分析。结果心肌病组心肌中组织蛋白酶LmRNA及蛋白表达水平均明显高于对照组,两组比较,差异有高度统计学意义(P值均<0.01);DCM患者心肌组织蛋白酶LmRNA表达水平与射血分数呈显著负相关(r=-0.884,P<0.01)。结论组织蛋白酶L过度激活可能在扩张型心肌病的发病机制中起重要作用。

The expression and significance of myocardial cathepsin L in dilated cardiomyopathy

Objective To clarify the expression of myocardial cathepsin L and its significance in the pathogenesis of dilated cardiomyopathy (DCM).Methods Myocardial tissue specimens derived from 20 patients undergoing orthotopic cardiac transplantation and 5 normal myocardium samples collected at autopsy from sudden death as controls were studied. The expression of cathepsin L was detected with immunohistochemistry,real time PCR and Western Blotting, respectively. At the same time,the relationship between the Cathepsin L mRNA expressional levels and the myocardial function(ejection fraction,EF) was investigated.Results The expression levels of cathepsin L mRNA and protein in DCM group were markedly elevated compared with those in control group and the expression levels of cathepsin L mRNA had significantly negative correlation with the myocardial function(ejection fraction,EF).Conclusion (Cathepsin) L is markedly elevated in DCM myocardial tissue and it may participate in the pathogenesis of DCM.