Objective     To explore the feasibility of preventing bile duct restenosis with the stent treated with

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I and to elucidate the mechanisms of the inhibition of the smooth muscle cell proliferation and the increase of apoptosis after bile duct injury in dogs.      Methods     The experimental dogs were randomly divided into common stent

group and

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I stent group

each of 6 animals. Duct was injured with cutting anastomosis. After formation of duct stenosis 90 d post operation

common stents and

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I stents were inserted in the end of the bile common duct of the 2 groups respectively. Morphological study on the duct

immunohistochemistry for P53

proliferating cell nuclear antigen (PCNA) and smooth muscle actin (SMA)

the radiation of the peripheral blood and tissue around the stent were studied.      Results     The utmost intimal thickness of bile duct was found to be obviously less in the

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I stent group compared to in common stent group after 90 d

and the percentages of the stenosis of the bile duct were (53.72±13.89) % and (17.34±9.28) %

respectively (

P

<

0.05). The circumference and area of bile duct lumen were obviously larger compared to that in the common stent group (

P

<

0.05). The expressions of PCNA and SMA in biliary smooth muscle cells were weaker in

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I group than in the common group

and that of P53 was obviously up-regulated.      Conclusion    

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I stent may inhibit the proliferation of smooth muscle cells and prevent the restenosis of bile duct.