胆总管结扎诱发大鼠肝外胆汁淤积的动态病理变化研究

Study on Dynamic Pathological Change of Extrahepatic Cholestasis in Rats Induced by Common Bile Duct Ligation

目的:观察胆管结扎(BDL)诱发大鼠胆汁淤积形成过程中模型肝组织病理动态变化特点。方法:行胆总管三段结扎术复制大鼠肝外胆汁淤积模型;于大鼠胆总管结扎第3 d、7 d、14 d分别随机处死3只假手术组、5只模型组大鼠取材,21 d时处死剩余大鼠取材,观察肝组织病理学变化,肝组织纤维化程度。结果:与假手术组比较,模型组3 d时肝组织小叶周边以及汇管区见胆管上皮细胞增生,并伴有少量的单核炎性细胞浸润;7 d时胆管上皮细胞明显增生,可见少量肝细胞点状坏死。14 d时胆管上皮细胞增生范围扩大,有胶原纤维增生。21 d时增生的胆管上皮细胞形成小胆管,增生的小胆管和纤维母细胞、胶原纤维改建原有的肝小叶而形成假小叶。肝细胞与增生的胆小管相比明显减少,剩余的肝细胞形态结构尚正常。结论:BDL胆汁淤积大鼠模型主要病理改变有肝细胞减少、胆管上皮细胞增生、胶原增生和沉积,此动态病理变化程度在21 d内随造模时间延长而加重。

Objective ： Observing the pathological change characteristics in the model liver tissue of rat cholestasis induced by BDL. Methods：Common bile duct ligation in three segment was performed to establish the cholestasis model out of the rat liver; five rats from the model group and 3 rats from the sham-operation group were taken randomly when the third day, the first week and the second week separately after the common bile duct ligat^on and were killed for getting the requisite material;the rest rats were all killed when the third week for getting the requisite material; we observed the pathological change of the liver tissue and the degree of the hepatic fibrosis. Results ： Compared with the sham-operation group, in the model group when the third day there are some new epithelia like small bile ducts, a few inflammatory cell infiltrations and a little collagen deposition in the portal area and the lobule perimeter. When the first week there are the expanding portal area and the obvious hyperplastic bile duct epithelia like wreath, the increasing collagen deposition around hyperplastic bile duct and a few hepatocyte necroses. When the second week there are continually increasing hyperplastic fiat bile duct epithelia with wide duct and incrassation of the peripheral basement membrane and the collagen fiber. When the third week the hyperplastic bile duct epithelia are like the nodules or evolve into the small bile ducts, and collagen fibers proliferate extensively;small bile ducts,the fibroblast, collagen fibers and the capillary vessels all form into the membrane -like intervals, which are connected,bun- dled and segmented with the neighbouring intervals ; Compared with the hyperlastic bile ducts, the hepatocytes are relatively decreasing ; the morphological structures of the rest hepatocytes are still normal. Conclusion ： The pathological change of choleasstis in rat liver induced by BDL are characterized with the hyperplasia of the bile duct epithelia, the decrease of hepatocyte and the collagen hyperplasia and deposition, and these pathological change have a positive correlation with the BDL time within 3 weeks.