氮自由基(NO)在鼠肝异种移植超急性排斥反应中的作用

Role of reactive nitrogene species in hyperactue liver rejection after heterotransplantation in rats

目的 应用大鼠肝脏灌注模型研究氮自由基在异种移植超急性排斥反应中的作用。方法 SD大鼠 18只分为 3组 ,每组 6只 ,分为鼠血灌注鼠肝组、人血灌注组、N 乙酰半胱氨酸 (NAC)治疗人血灌注鼠肝组。全麻下分离出门静脉、肝上下腔静脉并插管 ,缺血 30min后 ,原位灌注鼠肝 2h ,在不同时间取血检测氮自由基 (NO)、肝功能 (ALT)。结果 在异种灌注组 ,NO、ALT的升高均明显高于对照组 ,NAC的治疗抑制了异种灌注组的NO、ALT的升高 ,保护了肝脏功能。结论 氮自由基可能参与了异种移植的超急性排斥反应 ,NAC可部分抑制这种反应并保护异种移植的大鼠肝脏功能。

Objective To evaluate the effect of reactive nitrogene species (RNS) and the ability of N-acetylcysteine (NAC) in hyperacute liver rejection after heterotransplantation in rats. Methods Eighteen SD rats were divided into 3 groups of isogenic group, xenogenic group and NAC-treated xenogenic group. Under general anesthesia, the portal vein and suprahepatic vena cava were dissected respectively. The liver was perfused in situ through the portal vein with cold Ringer's solution. After ischemia for 30 min, the liver was reperfused for 2 h. The blood samples were collected at different time phases for the measurement of RNS (nitrite and nitrate) and liver enzyme (ALT). Results The nitric radicals and ALT were significantly higher in xenoperfused group than in the isogenic group. The concentration of nitrite and nitrate was reduced after addition of NAC. Meanwhile, NAC could markedly prevent the increase of ALT. Conclusions Reactive nitrogene species might be involved in hyperacute rejection. N-acetylcysteine is able to remarkably reduce RNS and improve the function of xenoperfused rat liver.