Abstract
Using 62 canine models, the difference in the pathological changes of liver, choledochal duct and pancreas were studied in three groups of adult, puppy and neonate. The models of pancreatico-cholecystostomy (P-Cy) and pancreatico-choledochostomy (P-Ch) were created employing the technique which was described in the previous report. Creation of P-Ch in neonate puppy was technically impossible and only P-Cy has been created. Direct cholangiography and histological studies of these structures with HE, elastica van Gieson, Azan Maroly, PAS and alcian blue stainings were performed at 1 to 12 months after creation of the model. In cholangiographic findings in P-Cy models, there was no significant difference in choledochal dilatation among these three groups. In P-Ch models, the mean dilatation rate was 2.2 times in 5 puppies and 3.3 times in 17 adult dogs. In histopathological findings in P-Cy models, mucosal proliferation was less marked in neonatal puppies, while it was greater in puppies and adult dogs. In neonatal puppies, there was less cellular infiltration, and less decrease of the elastic fibers in choledochal wall. No tendency was observed, of predisposing the pathological changes of congenital biliary atresia or neonatal hepatitis. In histological changes of P-Ch model in adult dogs, mucosal thickening and proliferation were remarkable in choledochal and cholecystic mucosa. But there was no observation of true gastric or intestinal mucosal metaplasia in any animal in 12 months after creation of these models.
