供肝热和冷保存性缺血性损伤的超微结构观察

Ultrastructural changes derived from ischemic injury in donor liver caused by warm and cold preservation

目的:探索供肝热、冷缺血对肝组织的超微结构影响,并讨论与某些手术并发症发生的关系。方法:从我院实施的67例原位肝移植病例中选择9例移植前供肝活检组织病理学检查无明显形态学改变、供肝者临床肝功能正常、肝炎病毒及巨细胞病毒检测均为阴性的供肝组织进行透射电镜观察。结果:在供肝中央静脉周围肝细胞质中常有较多吞噬溶酶体,少数肝细胞核出现浅的切迹,胞质中线粒体明显减少,部分线粒体肿胀。少部分毛细胆管腔扩大,微绒毛肿胀,微绒毛芯中微丝束减少或消失。部分小叶间胆管上皮细胞凋亡,管腔中含凋亡小体及细胞碎片。少数小叶间静脉内皮细胞肿胀,胞质空泡变性,甚者内皮细胞脱离管腔,细胞质膜断裂。结论:供肝毛细胆管和小叶间胆管上皮细胞的损伤是保存性损伤引起轻度胆汁淤积的主要因素。而小叶间胆管周围小血管内皮细胞的损伤可能是导致小叶间胆管上皮细胞凋亡的直接原因。小叶间静脉内皮细胞的损伤使血管壁平滑度受损,血流减缓,加重肝细胞的缺氧。

Objective：To explore the effect of warm and cold iscbemia on ultrastructural change of liver tissue and its relationship to some complications after liver transplantation. Methods： Nine cases were selected from 67 transplantation donor livers before transplantation operation with the qualification of the normal histological structure under light microscope, normal range of liver function and negative results for the markers of hepatitis virus B, C, G, EBV and HSV in our hospital. The ultrastructural changes were observed under transmission electron microscope. Results：A number of phagosomes appeared in hepatocyte around the central vein in the selected donor liver tissues. A superficial nuclear notch, swelled mitochondria, and decreased mitochondria were found in some hepatocytes. Mild bile canaliculi injury could also be found in the hepatocytes such as dilated canlicular space, swelled microvilli, decreased or lost of filaments in microvillns core. Apoptotic bodies and cellular debris were often noticed in the epithelial cells of bile canaliculi lumen and interlobular bile duct. Some interlobular vein showed a mild injury i.e. , vacuolation of cytoplasm in endothelial cells, diruption of cellular membrane and separation of endothelial cells from basal membrane. Conelusion：Iscbemic injury in donor liver could be caused by warm and cold preservation,and injury of bile canaliculi and interlobular bile ducts might be the major cause of mild cholestasis in liver transplantation. The apoptosis of the epithelial cells may be related to the damage of interlobular bile ducts. The injury of endothelial cells may lead to the decrease of smoothness of vascular intimae, slow of blood stream and acceleration of hypoxia of bepatocytes.