摘要
目的探讨RhoA/ROCK通路在糖尿病大鼠心肌纤维化形成中的作用。方法高脂饮食联合腹腔注射小剂量链脲佐菌素(STZ)建立2型糖尿病大鼠模型。实验分为对照(NC)组,糖尿病(DM)组和法舒地尔干预(DF)组(每天腹腔注射10 mg/kg,分两次注射)。24周末,应用HE染色观察大鼠心脏组织形态;电子显微镜观察心肌的超微结构;Masson染色观察心肌胶原沉积情况;羟脯氨酸(HYP)检测心肌胶原含量;测定超氧化物歧化酶(SOD)活力和丙二醛(MDA)含量;免疫组化法检测一氧化氮合酶(eNOS)表达;Western blot法检测心肌中磷酸化肌球蛋白磷酸酯酶靶点亚单位1(MYPT1)表达,代表ROCK活性。结果糖尿病组大鼠较对照组大鼠心肌组织ROCK活性明显增强(P<0.01),MDA含量增高(P<0.01),SOD活力降低(P<0.01),eNOS表达明显下调(P<0.01),心肌胶原明显增多(P<0.01)。法舒地尔干预组大鼠较糖尿病组心肌组织ROCK活性显著降低(P<0.01),MDA含量降低(P<0.05),SOD活力增加(P<0.01),eNOS表达上调(P<0.05),心肌胶原明显减少(P<0.01)。结论 ROCK抑制剂法舒地尔抑制心肌组织氧化应激反应并上调eNOS表达,有效地减轻2型糖尿病大鼠心肌纤维化。
Objective To deternine whether the RhoA/ROCK pathway is involved in the pathogenesis of myocardial fibrosis. Methods The experimental type 2 diabetic rats were established by high fat diet combined with one-time intraperitoneal injection of low dose streptozotocin （STZ）. The rats were randomly divided into three groups： normal control group, diabetic group and fasudil group （intraperitoneal injection of fasudil 10 mg per kg every day, two in- jections）. At week 24, The cardiac histological changes were observed by hematoxylin-eosin staining, transmission electron microscopy and masson staining. The volume of collagen was evaluated by hydroxyproline （HYP）. The ac- tivity of the anti-oxidant enzymes （SOD） and malondialdehyde （MDA） in cardiac tissues were estimated by using commercially available kits. The expression of eNOS in cardiac tissues was assessed by immunohistochemistry stai- ning. The level of p-MYPT1 protein expression were examined by western blot. Results Compared to the control rats, the level of p-MYPT1 and the content of MDA were significantly elevated in the hearts of the diabetic group（ P 〈 0. 01 ）, but the activity of SOD and the expression of eNOS were significantly lower than those of the NC group rats（P 〈 0. 01 ）. The concentrations of collagen （MCC） in myocardial tissue of the DM group were higher （P 〈 0. 01 ）. The fasudil group elevated the activities of SOD and the expression of eNOS （both P 〈0. 01 ） but re- strained the level of p-MYPT1 and the content of MDA （P 〈 0. 01, P 〈 0.05 ）. The concentrations of MCC was lower （P 〈 0. 01 ）. Conclusions ROCK inhibitor fasudil, ameliorates myocardial fibrosis in diabetic rats potentially through inhibiting oxidative stress and up-regulating eNOS expression.
出处
《基础医学与临床》
CSCD
北大核心
2014年第2期216-221,共6页
Basic and Clinical Medicine
基金
河北省卫生厅重大课题资助项目(20090007)
