ABSTRACT
Objective To observe the expression and distribution of myofibroblasts in the healing process of bile duct and discuss its function and significance in the process of iatrogenic biliary stricture formation. Methods A model of trauma-repair of bile duct in the dog was made . The anastomosis tissues on week 1,3 and month 3,6 after operation were studied with TEM and immunohistochemical SP staining of SMA. Results Myofibroblasts functioned actively and lasted for the whole process, extracellular matrix overdeposited. SMA staining was observed in myofibroblasts and highly expressed from 1 week to 6 months after operation. The consequence easily leaded to scar contracture and anastomoctic stenosis. Conclusion Myofibroblast is the main cause of scar contracture of bile duct.