[Alterations of the mucin components in bile duct epithelium associated with proliferating cholangitis--an experimental study].

Chronic proliferating cholangitis was accompanied by intrahepatic lithiasis, and its detail has not been reported. In this study, the alterations of mucin components were serially investigated using the experimental rabbit model. The proliferating cholangitis was induced by inserting a polyethylene tube to the choledochus through the papilla under laparotomy. The respective five animals were sacrificed 1, 3, 7, 10, 14, and 28 days after the surgery. The animals undergoing Sham operation were defined as control group (n = 5). The alterations of mucin components were determined through histochemical stainings for mucin: AB-PAS (pH 2.5) and AB (pH 1.0) stainings, and also for lectins: wheat germ agglutinin (WGA), Ricinus communis agglutinin (RCA), concanavalin A (Con A), Dolichos biflorus agglutinin (DBA), peanut agglutinin (PNA), soybean agglutinin (SBA), and Ulex eulopeus agglutinin (UEA-I) stainings. In the cholangitis epithelium, the mucin-stainings were temporarily augmented by acid mucins on day 3 and 7, followed by increase in neutral mucins. The significant increases in DBA, SBA, PNA, and RCA were also observed by lectin-staining, and the staining patterns of the former two and the latter two lectins were analogous to those of the neutral and acid mucin, respectively. DBA and SBA are specific to D-N-acetyl-D-galactosamine (DNADG), while PNA and RCA to D-galactose (DG); augmentations of the neutral mucins showed that DNADG and DG were closely related to mucous alterations in the proliferating cholangitis. The quantitative and qualitative alterations of the neutral and acid mucins may play an important role in the development of lithiasis.