Analysis of hepatic microcirculation during liver ischemia and reperfusion using in vivo microscopy

本研究的目的是利用活体显微技术分析临床肝移植和肝切除术中不可避免的肝缺血和再灌注过程中的肝脏微循环。为了开发新的治疗策略，我们尝试抑制中性粒细胞对血管内皮的粘附。建立大鼠肝移植模型，取肝移植片，在4ºC的UW溶液中保存18小时。植入后用活体显微镜观察肝脏微循环。存储肝和移植肝的血流灌注率（64%）明显低于未移植对照肝（99%）。肝移植物再灌注24小时后，嗜中性粒细胞黏附窦内皮（328/mm^2）和窦后小静脉（psv）明显增加。利用FK5O6和抗中性粒细胞粘附分子抗体，在储存18小时的肝脏植入前30分钟和植入后6小时静脉注射抗cd11b / cd18单克隆抗体（克隆号1B6， Repligen Co., Ltd.）。根据移植后24小时估计的血清ALT水平，抗体治疗显著提高了移植物存活率（治疗组为100%，对照组为50%），并减少了肝脏再灌注损伤。这与中性粒细胞粘附到窦内皮的显著抑制（81/mm^2）有关。免疫抑制剂FK506也有类似的效果；通过减少永久粘附在肝窦上的中性粒细胞的数量（60分钟后，fk处理动物为15.4/mm^2，对照组为67.9/mm^2），预防了低温保存和移植后的氧化性肝损伤。结论这些研究明确了中性粒细胞在肝缺血再灌注损伤中的致病作用，提示临床可能使用FK506和抗中性粒细胞粘附抗体治疗肝缺血再灌注损伤。少

BackgroundThe aim of the studies were to analyze, using the in vivo microscopic technique, the hepatic microcirculation during liver ischeniia and reperfusion, which was unavoidable in clinical liver transplantation and hepatic resection. In order to develop the new therapeutic strategies, inhibition of neutrophil adherence to vascular endothelia was attempted.Results1. Neutrophil adherence to hepatic vascular endothelia In a rat liver transplantation model, the liver graft was harvested and stored for 18 hours at 4ﾟC in UW solution. Then the hepatic microcirculation was investigated using in vivo microscopy following implantation. Sinusoidal perfusion rates were significantly lower in stored and transplanted liver (64%) compared with non-transplanted control liver (99%). Neutrophil adhesion to both sinusoidal endothelium (328/mm^2) and postsinusoidal venules (PSVs) were remarkably increased 24 hours following reperfusion of the liver graft.2. Amelioration of ischemia/reperfusion injur … More y using FK5O6 and anti-neutrophil adhesion molecule antibodyAn anti-CD 11b/CD 18 monoclonal antibody (clone 1B6, Repligen Co., Ltd.) was intravenously administered 30 minutes before and 6 hours after implantation of the 18-hour stored liver. The antibody therapy significantly improved graft survival (100% in the treated animals and 50% in the control) and reduced reperfusion injury to the liver as estimated serum ALT levels at 24 hours following transplantation. This was associated with significant inhibition of neutrophil adhesion to the sinusoidal endothelium (81/mm^2). An iMmunosuppressant, FK506, had similar effect ; prevented oxidative hepatic injury following cold preservation and transplantation by reducing the number of neutrophils permanently adhering to the sinusoids (15.4/mm^2 in FK-treated animals and 67.9/mm^2 in the control at 60 minutes following).ConclusionThese studies clearly demonstrated the causative role of neutrophils in hepatic injury following ischemia and reperfusion and suggested the possible clinical use of FK506 and antibody against neutrophil adhesion for the therapy. Less