肝吸蟲感染및 發癌物質에 依한 白鼠膽管上皮細胞 微細構造의 變化 = Effects of Clonorchis Infection and Carcinogens on Ultrastructural Changes of Biliary Epithelial Cells in Rats

다국어 초록 (Multilingual Abstract)

The effects of carcinogens, 3'-methyl-4-dimethylaminoazobenzene(3'-MeDAB) and aflatoxin B_1 on ultrastructural changes of biliary epithelial cells in the rats experimentally infected with Clonorchis sinensis were investigated using male rats of the Sprague-Dowley strain.
The animals were divided into 5 groups : group I, given 50 Clonorchis metacercariae alone ; group Ⅱ-a, treated with 0.03% 3'-MeDAB alone for 12 weeks; group Ⅱ-b, treated with 1.0ppm aflatoxin B_1 alone for 12weeks : group Ⅲ-a, given 50 metacercariae at the beginning of the 12 weeks treatment with 3'-MeDAB and group Ⅲ-b, treated with 50 metacercariae plus 1.0ppm aflatoxin B_1. Since the 4th week of experiment, ultrastructures of epithelial cells were observed, using transmission electron microscope.
In group I, some elaborate interwoven folds of lateral cytoplasm forming labyrinths of interconnected intercellular space, variety in nuclear shape and marked proliferation and swelling of rough endoplasmic reticulum were characteristic. In groups Ⅱ-a and Ⅱ-b, remarkable enlargement of nuclear size, increase of chromatin granules along the inner membrane of nucleus and nucleolar margination were prominent. On the other hand, group Ⅲ-a or group Ⅲ-b revealed mostly combined findings of those shown in Clonorchis-infected rats and carcinogen-treated ones. Furthermore, the presence of liver fluke and carcinogen led to neoplastic change.
In general, treatment with 1.0ppm aflatoxin B_1 alone(group Ⅱ-b) or 1.0ppm aflatoxin B_1 plus Clonorchis metacercariae(group Ⅲ-b) resulted in much earlier onset of alterations than that with 0.03% 3'-MeDAB alone(group Ⅱ-a) or plus metacercariae(group Ⅲ-a) throughout the observation. Despite differences in time of onset of alterations, they appeared to be essentially of the same order in cases of groups Ⅱ-a and Ⅱ-b, or groups Ⅲ-a and Ⅲ-b, respectively.
In conclusion, it was clearly evidenced that Clonorchis infection plays an important role as a promotor in cholangiocarcinogenesis in the rats treated with 3'-MeDAB or aflatoxin B_1.