Liver transplantation - studies of hemodynamics and preservation -

1. (1)肝移植的血流动力学研究：采用犬肝移植模型，进行无肝期的血流动力学研究。采用肝素化导管（Anthron）作为V-V转流，认为无肝期是一种低动力状态，伴有低血容量，肝切除前充分输血和多巴酚丁胺是有效的。(2)部分肝移植（partial liver transplantation，pLTx）：采用Anthron作为门静脉转流器，在保留受体下腔静脉（IVC）的情况下，对犬进行占全肝重量70%的左侧pLTx移植。最长生存期为28天。相反，右室侧pLTx，其重量为30%，显示门静脉高压15 mmHg（前，7 mmHg），并在24小时内死亡。当供、受者肝脏重量比超过70%（供体/受体）时，体重比2.0：1），术后门静脉压力下降，受者可行走。认为犬右侧pLTx移植后即刻需要70%的肝脏维持生命。2.器官保存：从能量代谢的角度研究缺氧和热缺血对大鼠肝脏的影响。(1)能量代谢的动态平衡由ATP → AMP →黄嘌呤→次黄嘌呤，表明ATP是通过从头合成途径合成的。(2)采用70%部分肝缺血模型，研究了热缺血时肝脏能量代谢的变化及药物对肝脏的影响。能量代谢变化与模型和药物相同，血栓素A_2合成酶抑制剂（CV-4151，Takeda Pharm. Co.），蛋白酶抑制剂（乌司他丁，Mochida Pharm. Co.）和吲哚美辛增加了存活率并改善了肝脏中的能量代谢。

1. (1) Hemodynamic study of liver transplantation: Hemodynamic study during anhepatic phase was done in canine liver transplantation. It was thought to be a hypodynamic state with hypovolemia during anhepatic phase using heparinized catheter (Anthron) as V-V bypass, in which sufficient transfusion before hepatectomy and dobutamine were effective. (2) Partial liver transplantation (pLTx) : Lt-side pLTx, which accounts for 70% of the whole liver weight, was done in dog, preserving IVC of the recipient, with use of Anthron for portal vein bypass. The longest survival was 28 days. On the contrary, Rt-side pLTx, which weights 30% , showed portal hypertension by 15 mmHg (pre, 7 mmHg), and died within 24 hours. When the weight ratio of the liver between donor's and recipient's exceeded 70% (Donor/Recip. body weight ratio; 2.0 : 1), portal vein pressure decreasedand the recipients could walk after the operation. Seventy percent of liver was thought to be necessary to sustain the life immediately after transplantation in Rt-side pLTx in dogs. 2. Organ preservation: The influences of hypoxia and warm ischemia on liver were studied from the viewpoint of the energy metabolism in rats. (1) The dynamic balance of energy metabolism changed from ATP to AMP, xanthin and hypoxanthin, which indicated that atp were synthesized via de novo pathway. (2) Energy metabolic changes and the effect of drugs on liver in warm ischemia were studied with 70% partial liver ischemia model. The energy metabolic changes were the same as in (1) model and drugs, thromboxane A_2 synthetase inhibitor (CV-4151, Takeda Pharm. Co.), protease inhibitor (urinastatin, Mochida Pharm. Co. ) and indomethasin increased the survival ratio and improved the energy metabolism in the liver.