北五味子木脂素和北五味子粗多糖对异丙肾上腺素诱导小鼠心室重构作用的研究

目的研究北五味子木脂素（Schisandra lignans,SCL）和北五味子粗多糖（Schisandra chinensis polysaccharides,SCP）对异丙肾上腺素（Isoproterenol,ISO）诱导小鼠心室重构的保护作用,并探讨其初步机制.方法采用连续10 d皮下注射ISO的方法诱导小鼠心室重构模型.小鼠随机分为对照组、ISO组、SCL低、中、高3个剂量组和SCP组,采用灌胃给药方法.实验结束后计算小鼠心脏重量指数;观察心肌病理形态学改变情况;HE染色后测定心肌纤维直径（MD）;分光光度法测定心肌组织中羟脯氨酸（HYP）含量、一氧化氮（NO）含量、一氧化氮合酶（NOS）活性、超氧化物歧化酶（SOD）活性和丙二醛（MDA）含量.结果与对照组相比,ISO组小鼠心脏重量指数、HYP含量和MDA水平明显升高（P〈0.05或P〈0.01）,NOS和SOD活性及NO水平明显下降（P〈0.05或P〈0.01）;与异丙肾上腺素组相比,北五味子木脂素和北五味子多糖组能明显降低心脏重量指数（P〈0.05或P〈0.01）,改善心肌病理学变化,抑制心肌组织中羟脯氨酸含量,提高SOD活性,降低MDA含量,提高心肌中NOS活性和NO水平（P〈0.05,P〈0.01或P〈0.001）.结论北五味子木脂素和北五味子多糖对ISO诱导的小鼠心室重构具有抑制作用,其机制可能与提高NOS活性和NO水平、清除氧自由基、提高机体的抗氧化能力有关.

Effects of Schisandra Lignans and Polysaccharides on Ventricular Remodeling Induced by Isoproterenol in Mice

Objective To study the effects of Schisandra lignans（SCL） and Schisandra chinensis polysaccharides（SCP） on ventricular remodeling induced by isoproterenol（ISO） in mice and explore its preliminary mechanism.Methods Ventricular remodeling model was induced by subcutaneous injections of ISO for continuous ten days.Mice were randomly divided into control group,ISO group,positive control drug captopril（CAP） group,low-dose,middle-dose,high-dose SCL groups and SCP group by intragastric administration. Cardiac mass index of mouse was calculated after experiment,the changes of myocardial pathological morphology were observed,myocardial fiber diameter（MD） was measured by HE staining;hydroxyproline（ HYP） content,nitric oxide（ NO） content,nitric oxide synthase（NOS） activity,superoxide dismutase（ SOD） activity and malondialdehyde（ MDA） content in myocardial tissue were measured by spectrophotometry. Results Compared with those in the control group,the heart weight index and HYP content in ISO group were significantly increased（P〈0. 05 or P〈0. 01）,the NOS and SOD activity were decreased（P〈0. 05 or P〈0. 01）. Compared with the ISO group,three doses of SCL and SCP could reduce heart weight index obviously（ P〈 0. 05 or P〈 0. 01）,improve the myocardial pathologicalchanges,inhibit HYP content,increase SOD activity and reduce MDA content,and enhance NOS activity and NO level in myocardium（ P〈0. 05,P〈0. 01 or P〈0. 001）. Conclusion Schisandra lignans and Schisandra chinensis polysaccharides have inhibitory effects on ventricular remodeling induced by ISO in mice,its mechanisms may be related to increasing NOS activity and NO level,scavenging oxygen free radicals,enhancing the antioxidant ability.