冷缺血对大鼠小体积肝移植肝再生的影响

Influence of cold ischemia on rat liver regeneration after small-for-size liver transplantation

目的探讨冷缺血对大鼠小体积肝移植术后肝再生的影响。方法本组在2002年9月～2004年8月利用大鼠肝总量30%原位肝移植模型,实验分为肝总量70%肝切除组(C组)和冷缺血1、3、5h组(E1、E2、E3组),观察1w生存率及肝重量/受体原肝重量比值(EGW/RLW),并检测术后1、2、3、7d肝细胞增殖活性及肝组织学变化。结果E1组1w生存率及EGW/RLW分别达100%和95%,均明显高于E2、E3组(P均<0.05);E1、E2、E3组均于术后2d达到增殖高峰,其中E1组峰值显著高于E2、E3组(P<0.001),且与C组峰值无差异(P>0.05);组织学检查见E1组肝细胞核分裂明显活跃。结论冷缺血1h的小体积供肝和70%肝切除后肝脏具有同样的增殖活性,仅增殖高峰稍晚;冷缺血超过3h严重影响小体积供肝的再生能力和受者的存活率。

Objective To explore the effect of cold ischemia on regeneration of small-for-size liver grafts. Methods From September 2002 to August 2004 30% orthotopic liver transplantation （30%OLT）was performed in a syngeneic strain combination. Cold ischemic time of the grafts was set to 1,3 and 5 hours,respectively （Experimental group, El, E2,E3）. The 1-week survival rates as well as graft weight to recipient liver weight ratios （EGW/RLW）were assessed.The proliferative rate of the small-for-size liver grafts were evaluated by Bromodeoxyuridine （BrdU） incorporation method on postoperative day （POD） 1, 2,3 and 7,respectively,and compared with those of the remnant liver after 70% partial hepatectomy （Group C）. The morphological changes were also observed. Results The 1-week survival rate and EGW/RLW of Group E1 were reached 100% and 95% ,respectively, which were significantly higher than those of Group E2 and E3 （P all 〈0.05）. Although the proliferative rates of all the experimental groups peaked on POD 2, the peak level of Group E1 showed no difference while compared to that of Group C（P〉0.05）,but it was significantly higher than those of Group E2 and E3 （P all〈 0.001）. Histological analysis also revealed a higher number of mitosis in Group E1 on POD 2 and 3.Conclusion The small-for-size liver grafts in 1-hour cold ischemia are capable of regeneration similar to the situation following 70% partial hepatectomy, with a slightly postponed time course. Duration of cold ischemia over 3 hours is associated with impaired regeneration and reduced survival rate.