Effectiveness of chemical biliary duct embolization for chemical hepatectomy

Abstract

The high recurrence of hepatolithiasis and high operative trauma of hepatectomy necessitate new therapeutic approaches. Thus, this study was designed to (i) investigate the effectiveness of chemical biliary duct embolization (CBDE) for chemical hepatectomy; and (ii) to determine the mechanism of CBDE. The median biliary ducts in rats were injected with phenol or absolute ethanol alone, or in conjunction with cyanoacrylate. The effectiveness of CBDE for chemical hepatectomy was assessed by investigating histology, in situ hybridization for Fas and transforming growth factor (TGF)-beta1, immunohistochemistry for alpha-smooth muscle actin, and reverse transcription-polymerase chain reaction (RT-PCR) for procollagen I mRNA. Histologically, phenol or absolute ethanol plus cyanoacrylate could embolize the targeted bile duct and promote hepatic fibrosis and atrophy in the embolized lobe better than using phenol or ethanol alone. In addition, CBDE accelerated hepatocellular apoptosis via up-regulation of Fas, thereby resulting in the death of hepatocytes, which were replaced by proliferative bile ductules and collagen. Importantly, the hepatocytes disappeared completely in the periphery of the embolized lobe, thus achieving the desired effects of chemical hepatectomy. Further investigation indicated that CBDE initiated progressive fibrogenic processes of chemical hepatectomy via up-regulation of TGF-beta1, which greatly enhanced the synthesis of collagen. Indeed, higher levels of TGF-beta1 and procollagen I mRNA were observed in the phenol embolization group than in any other group. Chemical biliary duct embolization, especially using phenol plus cyanoacrylate, might achieve the effects of chemical hepatectomy.