ABSTRACT
A method of isolation and culture of extrahepatic bile duct epithelial cells from Holstein cows has been established for detection of carcinogens in relation to bile duct cancer. Cells were isolated by digestion with Dispase followed by scraping of the mucosa. The integrity, the epithelial character and the purity of cells isolated were confirmed by electron microscopy. By the use of this culture induction of unscheduled DNA synthesis by chemicals which are capable of developing bile duct cancers in experimental animals, were assessed autoradiographically with or without addition of S-9 mixture. MNNG and ENNG induced UDS, which was not influenced by S-9 mixture. MCA elicited UDS only if S-9 mixture was added. Regardless of the presence of S-9 mixture, DMN failed to induce UDS but AFB1 induced UDS dose-dependently. The contact routes of the carcinogens with bile duct cells were established and this culture system way be an useful tool for the detection of biliary tract carcinogens.