法舒地尔对压力超负荷大鼠心脏的肌成纤维细胞表型分化的影响

Impact of Fasudil on cardiac myofibroblast differentiation in pressure overload rats

目的 Rho激酶介导的肌动蛋白细胞骨架重组在肌成纤维细胞(MFB)表型分化中具有重要作用。本实验拟观察Rho激酶抑制剂法舒地尔对压力超负荷大鼠心脏MFB表型分化的影响。方法采用腹主动脉缩窄法建立压力超负荷诱导的心肌纤维化大鼠模型。假手术组(Sham组)仅分离但不予结扎腹主动脉。术后4周末,将存活大鼠按随机数表法分为模型组(Model组)、法舒地尔高剂量组(FH组)和法舒地尔低剂量组(FL组)。药物干预4周末,观察大鼠心肌病理学改变,并检测心肌羟脯氨酸(HYP)含量,评估心肌纤维化程度;酶联免疫吸附法检测血浆和心肌血管紧张素Ⅱ(AngⅡ)含量;免疫组织化学法分析心肌磷酸化肌球蛋白磷酸酶靶蛋白亚基1(p-MYPT1)、α-平滑肌肌动蛋白(α-SMA)、骨桥蛋白(OPN)和转化生长因子β1(TGF-β1)的表达。结果 Model组大鼠心肌纤维化程度较Sham组明显加重,AngⅡ含量显著升高,p-MYPT1(0.063±0.009比0.029±0.014)、α-SMA(0.034±0.009比0.004±0.003)、OPN(0.043±0.007比0.012±0.006)和TGF-β1(0.058±0.019比0.019±0.009)的表达均明显升高(均为P<0.01);FH组和FL组大鼠心肌纤维化程度较Model组减轻,AngⅡ含量均显著下降,p-MYPT1(0.029±0.013和0.040±0.011)、α-SMA(0.016±0.006和0.027±0.007)、OPN(0.018±0.004和0.036±0.006)和TGF-β1(0.022±0.013和0.039±0.014)的表达也不同程度下降(P<0.01或P<0.05)。结论法舒地尔改善压力超负荷大鼠心肌纤维化的作用至少与部分抑制MFB表型分化有关。

Objective Rho kinase mediated cytoskeleton actin reorganization plays an important role in the phenotypic differentiation of myofibroblasts. The study is to investigate the effects of Fasudil- a Rho kinase inhibitor on myofibroblasts differentiation in pressure overload rats. Methods Pressure overload induced myocardial fibrosis rats models were established by abdominal aortic constriction. In sham group the abdominal aorta was just separated but not ligated. The 4 weeks after surgery, the operation survival rats were randomly divided into 3 groups ： control model group, Fasudil high dose group （ FH group） and Fasudil low dose group （ FL group）. And 4 weeks after the drug intervention, the degree of myocardial fibrosis was assessed as follows： pathologic changes were observed and hydroxyproline contents of the myocardium were determined; the content of angiotensin Ⅱ （Ang-Ⅱ ） was calculated by enzyme linked immunosorbent assay （Elisa） ; the expression levels of phosphorylated myosin phosphatase target subunit 1 （p-MYPT1）, a-smooth muscle actin （α-SMA）, osteopontin （OPN） and transforming growth factor-β1 （ TGF-β1 ） were analyzed by immunohistochemistry. Results Compared with the sham group, the degree of myocardial fibrosis in model group was aggravated variously, and the content of Ang- Ⅱ and the expression levels of p-MYPT1 （0.063 ±0.009 vs. 0.029±0.014）, α-SMA （0.034±0.009 vs. 0.004±0.003）, OPN （0.043 ±0.007 vs. 0.012 ±0.006） and TGF-β1 （0.058 ±0.019 vs. 0.019±0.009） were significantly increased （ all P 〈 0. 01 ）. Compared with the model group, the degree of myocardial fibrosis in FH group and FL group were relieved, and the content of Ang- Ⅱ and the expression levels of p-MYPT1 （0.029±0.013, 0.040±0.011）, ot-SMA （0.016 ±0.006, 0.027 ± 0.007）, OPN （0.018 ±0.004, 0. 036 ± 0. 006） and TGF-β1 （0. 022 ± 0. 013, 0. 039 ± 0. 014） were significantly decreased （ P 〈 0.05 or P 〈 0.01 ）. Conclusions The protection effect of Fasudil on myocardial fibrosis in pressure overloaded rats is at least partially related to the inhibition of myofibroblast differentiation.