Rho激酶抑制剂对百草枯中毒大鼠肺纤维化的干预研究

Intervention of Rho kinase inhibitor on pulmonary fibrosis induced by paraquat in rats

目的:探讨Rho激酶抑制剂对百草枯(PQ)中毒大鼠肺纤维化的影响及可能的机制。方法:将96只SPF级SD大鼠随机分为4组,每组24只,即正常对照组(Control组),Rho激酶抑制剂对照组(RI组),PQ染毒组(PQ组),Rho激酶抑制剂干预组(PQ+RI组)。在PQ灌胃第7、14、28天后,每组随机取6只大鼠,麻醉后处死,留取肺组织标本。碱水解法测定肺组织羟脯氨酸(HYP)含量,蛋白印迹法(Western blotting)测定Ⅰ、Ⅲ型胶原蛋白、结缔组织生长因子(CTGF)的表达。光镜下观察肺组织的病理变化。结果:与Control组相比,RI组无显著变化(P>0.05),PQ染毒组和RI干预组(均满足P<0.05)在第7、14、28天,HYP含量显著升高(P<0.05),I,Ⅲ型胶原蛋白、CTGF的表达也显著提升(P<0.05)。与PQ组比较,RI干预组在第7、14、28天HYP含量显著降低,Ⅰ、Ⅲ型胶原蛋白、CTGF的表达也显著下降。肺组织的病理结果显示PQ染毒组在灌胃给药后第28天的肺纤维化程度最严重,与之相比RI干预组在第7、14、28天肺纤维化程度均有减轻。结论:Rho激酶抑制剂,通过调节CTGF以及Ⅰ、Ⅲ型胶原蛋白的表达并且减少蛋白质沉积,对百草枯中毒导致的肺纤维化有明显的治疗作用。

AIM： To evaluate the effects of Rho kinase inhibitor on PQ-induced pulmonary fibrosis in rats and to explore its possible mechanisms.METHODS： 96 Sprague-Dawley male rats of specific pathogen free（ SPF） were randomly divided into four groups： control group（ n = 24）,Rho kinase inhibitor control group（ RI control group,n = 24）,paraquat poisoning group（ PQ poisoning group,n =24）,PQ ＋ Rho kinase inhibitor intervention group（ PQ ＋ RI group,n = 24）. On days 7,14,28 after taking oral administration of paraquat,6 rats were respectively selected from each group,which were anesthetized and killed immediately,and their lung tissues were saved. We assessed the hydroxyproline（ HYP） content of the lung tissue by alkalinehydrolysis and measured the expression of type Ⅰ,Ⅲ collagen protein,connective tissue growth factor（ CTGF）by western blotting. A light microscope was used to assess the pathological changes of lung tissues. RESULTS： Compared with the control group rats,there were no significant changes in the observation indexes of RI control group（ P〉0. 05）,in PQ poisoning group and RI intervention group on days 7,14,28（ all P〈0. 05）,the content of HYP increased obviously（ P〈0. 05）,the expression of type Ⅰ,Ⅲ collagen,CTGF,were increased significantly（ P〈0. 05）. Compared with the PQ group,the content of HYP decreased significantly and the expression of type Ⅰ,Ⅲ collagen,CTGF were decreased significantly in RI intervention group on days 7,14,28（ all P〈0. 05）. The pathological results of lung demonstrated that the degree of pulmonary fibrosis were most serious on 28 d after taking oral administration of paraquat in the PQ poisoning group,While the results were obvious reductive in RI intervention group on 7 d,14 d,28 d. CONCLUSION： Rho kinase inhibitor has obvious therapeutic effects on paraquat-induced lung fibrosis and it reduces the expression of CTGF,collagen Ⅰ,Ⅲ,and deposition of protein.