L-精氨酸对糖尿病大鼠肝损伤的保护作用

L-arginine in protecting diabetic rats from liver injury

目的探讨L-精氨酸(L-Arg)对糖尿病大鼠肝脏损伤的保护作用。方法给大鼠腹腔注射四氧嘧啶制备糖尿病模型,随机分为糖尿病组、L-Arg治疗组及正常对照组;用药4周末处死大鼠,检测肝细胞线粒体超氧化物歧化酶(Mn-SOD)、谷胱甘肽过氧化物酶(GSH-Px)活性及丙二醛(MDA)含量,肝组织细胞一氧化氮合酶(NOS)、Na+-K+-ATPase、Ca2+-ATPase活性以及NO含量。结果与正常组比较,糖尿病组大鼠肝细胞线粒体Mn-SOD、GSH-Px活性明显降低,MDA含量显著升高,肝组织细胞内NOS、Na+-K+-ATPase、Ca2+-ATPase活性明显降低;与糖尿病组比较,L-Arg治疗组大鼠肝细胞线粒体Mn-SOD、GSH-Px活性明显升高,且肝组织细胞内NOS、Na+-K+-ATPase、Ca2+-ATPase活性及NO含量显著升高。结论L-Arg对糖尿病大鼠肝脏损伤具有一定的保护作用。

Objective To study the efficacy of L-arginine in preventing and treating liver injury of experimental diabetic rats. Methods The diabetic rat models were established by injecting alloxan（160mg/kg,ip）. Rats were divided into three groups at random： diabetes group, L-arginine treatment group and normal group. The rats were sacrificed 4 weeks after using L-arginine（300 mg/kg）. The activities of Mn-SOD, glutathione peroxidase（GSH-Px） and the levels of MDA in mitochondria of liver of the three groups were determined. The activities of nittric oxide synthase （NOS） , Na^＋-K^＋-ATPase and Ca^2＋-ATPase and the contents of NO in liver tissues were examined . Results The activities of Mn-SOD and GSH-Px decreased significantly and the levels of MDA increased remarkably in mitochondria of liver, and the activities of NOS , Na^＋-K^＋-ATPase and Ca^2＋-ATPase in liver tissues also reduced obviously in diabetic rats compared with those in control group. The activities of Mn-SOD and GSH-Px were increased remarkably in mitochondria of liver, and the activities of NOS , Na＋-K＋-ATPase and Ca^2＋-ATPase and the contents of NO also increased significantly in liver tissues in L-arginine treatment group compared with those in diabetic group. Conclusions There is oxidative damage caused by oxygen free radicals in liver of diabetic rats. L-arginine can enhance anti-oxidation function and protect liver from oxidative damage to some degree.