冷保存和再灌注时肝内自由基生成的初步观察

INTRAHEPATIC GENERATION OF FREE RADICALS DURING LIVER CRYOPRESERVATION AND REPERFUSION:A Preliminary Observation

目的观察移植肝在冷保存与再灌注早期是否有氧自由基与一氧化氮（ＮＯ）产生，并探讨可能的发生机制。方法采用猪异体原位肝移植模型，分别测定移植肝冷保存后与再灌注早期肝灌洗流出液／血中脂质过氧化物丙二醛（ＭＤＡ）与ＮＯ浓度。并观察肝再灌注时入、出肝血中白细胞计数的变化。结果冷保存后肝灌洗流出液中ＭＤＡ与ＮＯ浓度有明显增高。门静脉血经肝再灌注后ＭＤＡ含量较入肝前显著增加，粒细胞显著减少，但ＮＯ浓度无明显变化。结论肝冷保存和再灌注早期均有氧自由基产生，但ＮＯ增加主要见于肝冷保存期。

Objective To investigate the intrahepatic generation of oxygen free radicals and nitric oxide (NO) during cold storage and early liver reperfusion, together with the possible mechanisms.Methods In a porcine model of orthotopic liver transplantation, the concentration of molonyliadehyde (MDA) and NO in in- and outflow (portal andhepatic venous) of the liver were determined following flushing the cryopreserved liver with Ringer's solution and early blood reperfusion, both via the portal vein. Meanwhile, the leucocyte count was done for portal and hepatic venous blood during portal reperfusion. Results MDA increased significantly in the hepatic outflow than in inflow after flush and blood reperfusion. However, the increase of NO in the hepatic outflow was found only after flush. The granulocyte count in hepatic venous blood was much less than in portal blood.Conclusion Oxygen free radicals are generated during both cold storage and early reperfusion. Nevertheless, NO occurs only in the former situation, not in the latter. Intrahepatic accumulation of leucocytes is probably involved in the generation of oxygen free radicals in early reperfusion of the liver.