Protective Effects Of Partial Portal Vein Arterialization On Ischemic Bile Duct Injury In Rats

Background:Ischemic cholangiopathy has been defined as ischemic damage to bile ducts due to impaired blood supply.Ischemic-type biliary injuries are commonly seen in liver transplantion andtranscatheter embolization or chemoembolization in patients with hepatocellular carcinoma.Unlike the hepatic parenchyma which has a dual blood supply from the hepatic arteries and portal vein,the biliary system depends exclusively on the arterial supply.Whether portal vein arterialization may extenuate the ischemic bile duct injury via arterioportal shunts was not clear though some clinical case reports support this hypothesis.Experimental research providing the theoretical basis lacks.Objective:1?To explore the surgical technique of partial portal vein arterialization(PPVA)in a Sprague-Dawley rat model.2?To explore the mechanisms of hepatic dearterialization-induced ischemic bile ductinjury and whether PPVA can attenuate this injury.Methods:1?Anastomosis of the hepatic artery to the portal vein was made to establish PPVA in a rat model via end-to-side.Complete hepatic arterial deprivation was achieved by disruption of the hepatic artery and the peribiliary vascular plexus,and then followed by the PPVA procedure.Techenique success rate and survival rate were examined.2?Male Sprague-Dawley rats underwent either complete hepatic arterial deprivation or partial portal vein arterialization,or both.Hepatic ischemia was evaluated using biochemical analysis,light microscopy and transmission electron microscopy.Hepatic ATP levels,the expression of hypoxia-and inflammation-associated genes and proteins,and the expression of bile transporter genes were assessedResults:1.The surgical technical success rate was 66.7%for the PPVA procedure.The operation time and occlusion of the portal vein were 25.8±1.lmin and 5.3±1.3min,respectively.The surgical technical success rate was 70%for the PPVA+BDI procedure.The operation time and occlusion of the portal vein were 30.1±1.6min and 4.0±1.2min,respectively.Patency of the anastomosis was confirmed by the ultrasonic examination during the re-operation.2.Complete dearterialization of the liver induced acute liver injury,as evidenced by the histological changes(e.g.,bile infarcts,bile leakage and biloma formation),significantly increased serum biochemical markers,decreased ATP content,increased expression of hypoxia-and inflammation-associated genes and proteins,and decreased expression of bile transporter genes.These detrimental changes were extenuated but not fully reversed by partial portal vein arterialization,which also attenuated ductular reaction and fibrosis in completely dearterialized rat livers. Conclusion:1?It is feasible to establish the PPVA and PPVA+BDI model in rats after learning curve completion.2?Complete hepatic dearterialization causes severe bile duct injury,which can be attenuated by the PPVA procedure.