Objective To determine whether local delivery of c-myc shRNA could inhibit hyperplasia and lithogenic potentiality in a rat model of chronic proliferative cholangitis (CPC) via specific blockade of the c-myc expression. Methods The CPC animal model (CPC group) was established via retrograde insertion of a 5-0 nylon thread into the common bile duct through Vater’s papilla. Three kinds of c-myc shRNAs were then respectively injected in c-myc shRNA group, which were included shRNA-1, shRNA-2, and shRNA-3, respectively. Negative control group and sham operation group were established for comparison. Subsequently, histopathological changes of bile duct wall were observed by HE, Massion, and PAS/AB staining; c-myc protein was detected by immunohistochemistry method; 5-bromodeoxyuridine (BrdU) protein was tested by immumofluorescence method; c-myc, Mucin 3, and Procollagen Ⅰ mRNAs were detected by real time PCR; Ki-67 protein was determined by Western blot; Activity of β-glucuronidase was measured by modified Fisherman method. Results ①Compared with the CPC and negative control groups, biliary tract mucosa epithelium (HE staining), submucosal acid mucinous gland (mid-blue staining, PAS/AB staining), and degree of over-hyperplasia of collagen fiber in bile duct wall (blue staining, Massion staining) were weaker in the c-myc shRNA group. ②The expressions of c-myc mRNA, Mucin 3 mRNA, Procollagen Ⅰ mRNA, Ki-67 protein, and β-G activity in the c-myc shRNA group were lower than those of the CPC and negative control groups (Plt;0.05), but higher than those of the sham operation group (Plt;0.05). Conclusion c-myc shRNA treatment could effectively inhibit the hyperplastic behavior and lithogenic potential of CPC, which might help to prevent the biliary restenosis and stone recurrence.
