一氧化氮在ConA诱发小鼠急性肝损害中的作用

目的：观察一氧化氮（NO）在刀豆素（ConA）诱发急性小鼠肝损害中的作用。方法：25只昆明小鼠随机分为5组，ConA(40mg/kg)自小鼠尾静脉注入复制急性肝损害，为ConA组；应用ConA前半小时，给予NO合成的抑制剂（L-NAME，5mg/只），为LN组；应用ConA前半小时，给予NO合成底物（L-精氮酸），为L-精氮酸组；单独给予L-NAME(5mg/只)者为L-NAME组；对照组只给予尾静脉注射生理盐水。各组8小时后取血分别测定丙氮酸转氮酶（ALT），取肝组织测定亚硝酸盐（NO2^-）和丙二醛（MDA）含量。结果：ConA造成肝损害后，肝组织中亚硝酸盐（NO2^-）较对照组显著升高；以L-NAME抑制NO合成，肝组织中NO2^-含量下降，肝细胞损害反而加重，且肝组织MDA增加，肝窦内血细胞淤集加重；L-精氮酸组未见明显的肝脏保护作用。结论：在ConA性肝损害中，NO通过消除氧自由基和抑制血细胞在肝窦内淤而发挥一定的保护作用。

Effects of nitric oxide on ConA-induced acute liver injury in mice

Aim To observe the possible effects of nitric oxide(NO)on ConA-induced acute liver injury in mice. Methods Twenty-five Kunming mice were randomly divided into five groups.ConA was injected by tail vein at does of 40 mg/kg to duplicate the model of acute liver injury,which was the ConA group.Pretreated with an inhibitor of NO synthesis(L-NAME)half an hour before ConA injection was the LN experimental group.Preteated with L-arginine half an hour before ConA injection was the L-arginine experimental group.L-NAME group was only given L-NAME before the injection of ConA.Saline only was injected in the control group.The blood samples were obtained respectively eight hours after ConA injection,and alanine aminotransferase activity(ALT)was tested.Then experimental liver specimen was obtained to detect nitrates(the stable products of NO)and MDA in all groups.Results Serum ALT activity increased significantly in L-NAME group than that of in ConA group while nitrates in the liver tissue declined,further more,MDA in liver tissue also increased greatly and vascular thrombosis became more serious in L-NAME group.No hepatic protective effects were found when pretreated with L-arginine.Conclusions NO plays a partial protective role in ConA-induced liver injury medicated by reducing oxygen radical-induced liver injury and preventing intro vascular thrombosis.