Pathologic changes in the common bile duct of an experimental model with pancreaticobiliary maljunction without biliary dilatation.

Abstract

Pancreaticobiliary maljunction (PBM), a congenital anomaly, causes regurgitation of pancreatic juice into the biliary tract, where it exerts a hazardous influence. However, changes in the common bile duct (CBD) remain obscure due to a lack of suitable experimental models. Using cats, we have developed an experimental model of PBM without bile-duct dilatation that allows the pure effects of PBM to be studied. Histologic and cellular kinetic changes in the CBD were analyzed in 6 controls and 9 experimental animals that survived for more than 6 months. CBD sections were stained with hematoxylin and eosin and a monoclonal antibody to the proliferating cell nuclear antigen (PCNA). Invaginations of the bile-duct epithelium or parietal sacculi increased, and peribiliary glands were well-developed. PCNA-positive cells significantly increased in the CBD, especially in the parietal sacculi and glands. It is concluded that PBM increases the cell cycle in CBD epithelium and subsequently developed peribiliary glands. These developed glands may be associated with the formation of protein plugs, often seen in patients with PBM.