【摘要】 目的 :了解外源性L Arg在肠缺血再灌注损伤中的作用及其机制。 方法 :30只雄性Wistar大鼠随机分为 5组 ,每组 6只 ,肠系膜上动脉分离结束前 10min静脉注射生理盐水 2 0ml(C组 ) ;缺血前10min静脉注射生理盐水 2 0ml(IR组 ) ;缺血前 10min静脉注射L Arg 2 0 0mg/kg(AIR组 ) ;再灌注前10min静脉注射L Arg 2 0 0mg/kg(IAR组 ) ;再灌注前 10min同时静脉注射L Arg 2 0 0mg/kg和N 硝基 L 精氨酸 40mg/kg(INAR组 )。 12 0min实验结束后 ,所有动物取距回盲瓣 5 0cm以上回肠肠断 15cm ,均分为 3段 ,分别测定各组肠粘膜PMN浸润数量、MDA含量和粘膜组织学Chiu分级 ;另取 36只大鼠 ,随机分为生理盐水对照组和L Arg实验组 (再灌注前 10min静脉注射L Arg 2 0 0mg/kg) ,每组再随机分为 3组 ,每组 6只。两组分别与缺血前、缺血 6 0min和再灌注 6 0min取小肠中段肠管 2 0cm ,测定小肠组织线粒体内Ca2 + 含量。结果 :再灌注前给予适量的外源性L Arg后 ,与C组相比 ,各组的肠粘膜PMN浸润数量、MDA含量、线粒体内Ca2 + 含量和粘膜组织学分级均无明显差异 (P >0 0 5 ) ;缺血前给予L Arg后 ,与IR组相比 ,上述各项指标除Ca2 + 含量外均明显减少 (P <0 0 5 ) ,但仍高于C组 (P <0 0 5 )。结论 :再灌注前给予外源性L Arg对?更多还原

【Abstract】 Objective: To study the effect of exogenous L-Arg on intestinal ischemia reperfusion and its mechanisms.Methods: Thirty Wistar rats were randomly divided into 5 groups(6 per group).The group venously injected with 2.0ml normal saline 10 minutes before the ending of superior mesenteric artery seperation(C).The group venously injected with 2.0ml normal saline 10 minutes before ischemia(IR).The group venously injected with L-Arg200mg/kg 10minutes before ischemia(AIR).The group venously injected with L-Arg200mg/kg 10minutes before reperfusion(IAR).The group venously injected with L-Arg200mg/kg and L-NNA40mg/kg 10minutes before reperfusion(INAR).15cm ileal segments were sampled 120minutes later and equally divided into 3 to determine the counts of mucosal PMN,content of MDA and mucosal histology scores.Thirty six rats were randomly divided into control and experimental groups(18 per group),each group was subdivided into 3 groups(6 per group).2.0cmileal segments were sampled before ischemia,60 ischemia and 60 reperfusion respectively to determine the counts of Ca 2+ in mitochondrion.Results: The difference between C and IAR was not significant(P>0 05),whereas AIR and IR was significant(P<0 05) .The effect of L-Arg venously injected before reperfusion was thorouly inhibited by L-NNA(an inhibitor of NOS).Conclusion: Exogenous L-Arg applied before reperfusion has remarkable protective effect on intestinal ischemia reperfusion in rats.Administration of L-Arg before ischemia also decreases to some extent the intestinal lesion induced by ischemia reperfusion更多还原