Orthotopic Autologous Liver Transplantation Research Articles

Effects of warm ischemia time on biliary injury in rat liver transplantation

To investigate the effect of different secondary warm ischemia time (SWIT) on bile duct injury in liver-transplanted rats. Forty-eight male inbred Sprague-Dawley rats were randomly assigned into four groups: a sham-operation group and three groups with secondary biliary warm ischemia time of 0 min, 10 min and 20 min. A rat model of autologous liver transplantation under ether anesthesia was established, and six rats were killed in each group and blood samples and the median lobe of the liver were collected for assay at 6 h and 24 h after hepatic arterial reperfusion. With prolongation of biliary warm ischemia time, the level of vascular endothelial growth factor-A was significantly decreased, and the value at 24 h was higher than that at 6 h after hepatic arterial reperfusion, but with no significant difference. The extended biliary SWIT led to a significant increase in bile duct epithelial cell apoptosis, and a decrease in the number of blood vessels, the bile duct surrounding the blood vessels and bile duct epithelial cell proliferation in the early postoperative portal area. Pathologic examinations showed that inflammation of the rat portal area was aggravated, and biliary epithelial cell injury was significantly worsened. A prolonged biliary warm ischemia time results in aggravated injury of the bile duct and the surrounding vascular plexus in rat autologous orthotopic liver transplantation.

Research of the effective mechanism of rosiglitazone to biliary ischemia-reperfusion injury in autologous liver transplantation

Objective To explore the effective molecular mechanism of PPAR-γligands rosiglitazone to biliary ischemia-reperfusion injury in autologous liver transplantation. Method A total of 40 SD rats were randomly （random number） divided into sham operation group （SO）, ischemia - reperfusion group （Ⅰ/R）, rosiglitazone （ROS） and GW9662 group, with 10 ones in each. The models, rat biliary ischemiareperfusion injury of autologous liver transplantation, were made by modified two-cuff technique. Tissues of the liver and bile ducts and blood of those models were evaluated by pathological and biochemical methods to make sure the models were made successfully or not. SO group suffered autologous orthotopic liver transplantation, and L/R group suffered both that and ischemia-reperfusion. ROS group were injected rosiglitazone （0.3mg/kg） via portal vein after having been done all as I/R. GW9662 group suffered all as ROS, and 10min later ,they were injected GW9662（0.3mg/kg） via portal vein. 4h after the experiment, tissues of livers and bilary ducts were taken to be tested by immunohistochemistry method, and the blood punctured from the right ventricular were taken to be determined by ELISA. ANOVA was used for statistical analysis.Results IL-1β, TNF-α and IL-6 were mainly expressed in the cytoplasm of hepatocytes and bile duct cells,while NF-κB was expressed both in the cytoplasm and nuclei. Expression of those proteins in L/R and GW9662 group was increased, significantly higher when compared to the SO and ROS （P 〈 0.05）. IL-1β,TNF-α and IL-6 in rat serum were simultaneously increased, and significantly higher than SO（P 〈0.05）.Compared with the SO, expressions of the IL-1 β,TNF-α and IL-6 were not significantly changed in ROS （P〉 0.05 ）but significantly increased in GW9662. Conclusions PPAR-γ ligand rosiglitazone took protective role in biliary ischemia-reperfusion injury in autologous liver transplantation. The mechanism correlates with the release of the IL-lα, IL-1β and TNF-α and other inflammatory mediators, which decreased as the expression of NF-κB inhibited by its antagonist. Key words: PPAR-γ; Rosiglitazone; Aotologous liver transplantation; Biliary injury; Ischemiareperfusion; lschemic type biliary lesion; NF-κB; Systemic inflammatory response syndrome

RhGH Attenuates Ischemia Injury of Intrahepatic Bile Ducts Relating to Liver Transplantation

To study the effect of rhGH administration on intrahepatic cholangiocytes relating to liver transplantation with ischemia of hepatic artery, and ultimately, clarify pathologic mechanism of the injury. Rat orthotopic autologous liver transplantation was performed first. Three hours later, the rats were grouped as followed: HAL (hepatic artery ligation) group; HAL + rhGH (hepatic artery ligation followed by rhGH administration) group; CON (without hepatic artery ligation) group. Specimen was collected after 7 d. ALT and ALP of serum were measured. The pathologic changes of bile ducts of liver tissue were observed. The number of bile ducts and blood vessels in portal area were counted. Immunochemistry for VEGF, VEGFR-2, VEGFR-3, GHR, and IGF-1R of intrahepatic cholangiocytes was performed. Cholangiocytes apoptosis was evaluated by TUNEL analysis. Cholangiocytes proliferation was evaluated by PCNA immunolabeling. ALT and ALP of HAL + rhGH group were significantly ameliorated compared with untreated animals (P < 0.05). ALT and ALP of HAL group were significantly higher compared with CON group (P < 0.05). In HAL group, the main injury of bile ducts was not reversible, whereas it was reversible in CON and rhGH groups. In HAL group, the number of bile ducts in portal area decreased, while the number of bile ducts not accompanying blood vessels increased (P < 0.05). In rhGH group, the number of bile ducts in portal area increased, while the number of bile ducts accompanying blood vessels increased compared with HAL group (P < 0.05). The expression of VEGF, VEGFR-2, VEGFR-3, GHR, and IGF-1R was significantly lower in HAL group than in CON group (P < 0.05). Following administration of rhGH to HAL rats, the expression of VEGF, VEGFR-2, VEGFR-3, IGF-1R, and GHR was significantly higher (P < 0.05). Administration of rhGH prevented increase in cholangiocytes apoptosis induced by HAL (P < 0.05). Administration of rhGH promoted increase in cholangiocytes proliferation held by HAL (P < 0.05). Administration of rhGH appears to attenuate ischemia injury of intrahepatic bile ducts relating to liver transplantation. This function is partly related to the capacity that rhGH inhibits the apoptosis of intrahepatic cholangiocytes and prompts the proliferation and angiogenesis by increasing the expression of VEGF, VEGFR2, VEGFR3, GHR, and IGF1-R.

Comparison of tolerance to ischemia-reperfusion injuries between different parts of extrahepatic bile duct during orthotopic autologous liver transplantation in rats

Objective:To observe the tolerance to ischemia-reperfusion injuries in different parts of extrahepatic bile duct during orthotopic autologous liver transplantation in rats,so as to lay a foundation for selection of anastomosis site during liver transplantation.Methods:Thirty SD rats were randomly divided into 3 groups:group Ⅰ,sham operated(n=6);group Ⅱ,1 h ischemia in biliary tract followed by 1 h reperfusion(n=12);and group Ⅲ,1 h ischemia in biliary tract followed by 2 h reperfusion(n=12).TUNEL assay,pathomorphology score and ultrastructural quantitative analysis were used to analyze the epithelia of hilar bile duct,proximal,and distal common bile duct.Results:The results of TUNEL assay and pathomorphology score were not significantly different between the proximal and distal common bile ducts in group Ⅱ(P0.05),but the injury was more serious in hilar bile duct compared with those of the proximal and distal common bile ducts(P005);the hilar bile duct had the most serious injuries as indicated by the changes of mitochondrial mean volume(V) and area density of microvilli(AMV),and the proximal common bile duct had the slightest injury(P0.05).In group Ⅲ,the most severe injury was found in the hilar bile duct,followed by distal common bile duct and proximal common bile duct in order(P0.05).Conclusion:The tolerance to ischemia-reperfusion is different in different parts of bile duct during liver transplantation,with the distal common duct having the best tolerance,which may be used for bile anastomosis during transplantation.