Application of Mitomycin C-eluting stent in biliary benign stricture

Abstract

Objective To produce a kind of biliary stent with Mitomycin C-eluting and evaluate the availability and safety in biliary benign stricture model of rabbit. Methods 36 New Zealand rabbits were fulgurize choledochus to establish model of biliary benign stricture. Rabbits were randomly divided into Mito-mycin C-eluting stent group 1 （ n = 12）, polyurethane stent group 2 （ n = 12） and control group 3 （ n = 12 ） one month later. General conditions, survival of the animals and changes in liver function were observed after surgery. The histological changes of bile duct were observed after 30 days. The immunohistochemistry SP method was used to measure transforming growth factor-β1 （TGF-β1） and a-Smooth muscle actin （α-SMA） expression. Results Stricture was improved in the two stent groups. In Mitomycin C-Eluting stent group to- tal bilirubin dropped from 5.56 μmol/1 to 0. 82 μmol/1, and in polyurethane stent group total bilirubin dropped from 6. 72 μmol/1 to 0. 87 μmol/1. The total bilirubin decreased in both two stent groups but no sta-tistically significant between the two stent groups, and there were no improvement in control group. Diameter of the stricture bile duct in group 1 was expanded bigger than in group 2 according to histology observation. Inflammatory cell infiltration and collagen fibroplasia in the submucosal were obviously observed in control group. The immunohistochemistry results showed that the TGF-β1 and α-SMA strongly expressed in the ste-nosis bile duct of group 3. The expressions in group 2 were lower than group 3, but higher than in group 1. And there was significant difference between the two stent groups （ P 〈 0. 05 ）. Conclusion The new Mito-myein C-Eluling stent is safe and provides enhanced local drug delilivery. It also can inhibit the form of Biliary scar to a certain degree. Key words: Biliary stricture; Milomycin C; Drug-eluling stent; Drug sustained-release