The proliferous rule of bile duct endothelium after the placement of metallic biliary stent:a study in canine

Abstract

To discuss the proliferous rule of bile duct endothelium after the placement of metallic biliary stent. The metallic biliary stent was placed at the inferior segment of common bile duct of canine after a percutaneous transhepatic puncture at cholecyst. All the stented dogs were assigned randomly to 4 group including A, B, C and D, each group had been under research for 1 month, 3 months, 12 months and 24 months. The expression of PCNA and Ki-67 in bile duct endothelium covered by the stent were calculated on the immunohistochemistry staining images and compared with those uncovered in each group, then the expression of PCNA and Ki-67 in bile duct endothelium covered by the stent were compared between every two adjacent groups. The thickness of bile duct wall covered by the stent were measured on the HE staining images and compared between every two adjacent groups. The t-test was performed for the statistics. The animal model were successfully set in 18 canines. The expression of PCNA and Ki-67 in bile duct endothelium covered by the stent were significantly higher than those uncovered in every group (P < 0.05), which got much high within 1 month after stenting (P < 0.05) and gradually raised up again from 3 months to 1 year (P < 0.05) after a period of relatively low proliferation. The thickness of the bile duct covered by the stent changed following the same rule as well. The metallic biliary stent indeed induced the proliferation of bile duct endothelium. This phenomenon enhanced gradually from 3 months to 1 year after stenting, and continued persistently after that.