Sergi Consolato, Gross Wolfgang, Mory Martin, Schaefer Michael, Gebhard Martha-Maria
Institute of Pathology, Innsbruck Medical University, Innsbruck, Austria.
J Surg Res. 2008 May 15;146(2):164-71. doi: 10.1016/j.jss.2007.05.024. Epub 2007 Jul 13.
Ischemia-reperfusion (I/R) injury in liver transplantation units and the influence of I/R injury on bile flow dynamics is being intensely investigated in various animal models, but the expression of intracellular intermediate filaments of biliary type as an early sign of cholestasis has not been yet explored.
We studied the hepatic elimination kinetics of indocyanine green (ICG), an exclusively biliary excreted cholephilic dye, and the functional and morphological integrity of liver cells in a canine liver transplantation model following I/R. During reperfusion following cold ischemia, we evaluated the ICG excretion curves, biochemical signs of liver damage, the bile canaliculus of the hepatocytes by electron microscopy, and the expression of intermediate filaments of cytokeratin type by immunohistochemistry.
Impairment of the biliary ICG excretion was directly related to ischemia time, but hepatocellular ICG uptake and bile flow rate were not significantly reduced. Liver enzymes increased as early as 6 h of ischemia and hepatocytes showed an increase of the bile canaliculus area. This was correlated to a membranous to cytoplasmatic staining of the cytoskeleton of the hepatocytes.
To the best of our knowledge, this is the first evidence of cholestatic changes starting early following cold ischemia in a canine isolated perfused liver transplantation model despite prompt recovery of the bile flow.
肝移植单位中的缺血再灌注（I/R）损伤以及I/R损伤对胆汁流动动力学的影响正在各种动物模型中进行深入研究，但作为胆汁淤积早期迹象的胆管型细胞内中间丝的表达尚未得到探索。
我们在犬肝移植模型中研究了仅经胆汁排泄的亲胆染料吲哚菁绿（ICG）的肝脏清除动力学以及I/R后肝细胞的功能和形态完整性。在冷缺血后的再灌注期间，我们评估了ICG排泄曲线、肝损伤的生化指标、通过电子显微镜观察肝细胞的胆小管以及通过免疫组织化学观察细胞角蛋白型中间丝的表达。
胆汁中ICG排泄受损与缺血时间直接相关，但肝细胞对ICG的摄取和胆汁流速并未显著降低。早在缺血6小时时肝酶就升高，并且肝细胞显示胆小管面积增加。这与肝细胞细胞骨架从膜性染色变为胞质染色相关。
据我们所知，这是首次在犬离体灌注肝移植模型中证明冷缺血后早期即开始出现胆汁淤积变化，尽管胆汁流动迅速恢复。
