103Pd radioactive stent inhibits biliary duct restenosis and reduces smooth muscle actin expression during duct healing in dogs.

BACKGROUND: This study was designed to assess the expression of smooth muscle actin (SMA) in the healing process after implanting a (103)Pd radioactive stent in the biliary duct, and to discuss the function and significance of this stent in preventing biliary stricture formation. METHODS: A model of biliary injury in dogs was made and then a (103)Pd radioactive stent was positioned in the biliary duct. The expression and distribution of SMA were assessed in the anastomotic tissue 30 days after implantation of the stent. RESULTS: SMA expression was less in the (103)Pd stent group than in the ordinary stent group. The (103)Pd stent inhibited scar contracture and anastomotic stenosis. CONCLUSION: The (103)Pd stent can reduce the expression of SMA in the healing process and inhibit scar contracture and anastomotic stenosis in the dog biliary duct.