大鼠心肌重塑过程中Axin蛋白质的表达变化

为观察大鼠心肌重塑过程中Axin蛋白质表达水平的变化,实验用颈静脉输注去甲肾上腺素(NE)和动静脉造瘘(AVF)方法复制大鼠心肌重塑病理模型,采用超声心动术检测心脏结构和收缩功能。取病理模型大鼠左心室以及分离培养的成年大鼠心肌成纤维细胞,采用Wester blot技术检测Axin蛋白质的表达水平。结果观察到,在颈静脉输注NE 3d后,大鼠心脏发生向心性心肌肥厚和心肌纤维化,其左心室的Axin蛋白表达水平较对照组显著升高。A-V造瘘术一周后引起大鼠离心性心肌肥厚,心肌无明显纤维化,心肌Axin表达量与对照相比无显著变化。在分离培养的成年大鼠心肌成纤维细胞,NE处理24h能明显升高Axin蛋白的表达水平。上述结果表明,大鼠心脏有Axin蛋白质表达,NE致大鼠心肌重塑过程中Axin蛋白表达显著增加,可能与该过程的心肌纤维化有关。

Alterations of Axin protein expression during cardiac remodeling in rats

The purpose of the present study was to observe the expression of Axin protein during cardiac remodeling in rats. Cardiac remodeling animal models were prepared with the methods of jugular venous norepinephrine (NE)-infusion or arterial-vein fistula (AVF). The ultrasonic parameters of rat hearts were recorded before sacrifice. The expressions of Axin protein were determined by Western blot in rat hearts from different remodeling models as well as cultured cardiac fibroblasts from adult rats. Cardiac concentric hypertrophy and fibrosis was induced by 3-day jugular vein infusion of NE in rats. The expression of Axin in the left ventricles increased significantly compared with that of the control group. Cardiac eccentric hypertrophy without fibrosis was induced by A-V fistula for one week in rats, and no change in Axin protein expression in the left ventricles was observed. In cultured adult rat cardiac fibroblasts, NE treatment for 24 h increased significantly the Axin protein level. It is therefore concluded that Axin protein was expressed in rat heart and increased significantly in left ventricles during NE-induced rat cardiac remodeling, which may be relevant to cardiac fibrosis.