化学発癌物質による肝前癌病変のclonalityに関する研究 ―Ornithine Carbamoyltransferaseモザイクマウスを用いた酵素組織学的解析―

概要

論文の詳細を見る
Sparse-fur with abnormal skin and hair (Spf-ash) mice are deficient in ornithine carbamoyltransferase (OCT) activity. Since the deficiency of OCT is inherited as an X-linked dominant trait, the liver of heterozygous Spf-ash females shows mosaicism in regard to OCT due to an inactivation of one of two X-chromosomes during embryogenesis. We induced enzyme altered foci and nodules, presumptive preneoplastic lesions for hepatocellular carcinomas, by diethylnitrosamine (DEN) and phenobarbital (PB) in the liver of heterozygous Spf-ash mice (Spf-ash×C3H F1), and investigated the clonality of the lesions by simultaneous histochemical staining for OCT and γ-glutamyl transpeptidase (GGT). All GGT positive lesions having a size from 3 cells to a few mm in diameter were either positive or negative for OCT, and no mosaic lesions were detectable. The result indicates that all GGT (+) lesions have clonal proliferation. In addition to the development of GGT (+) lesions, the average diameter of mosaic patches were 4 times greater in DEN-PB treated mice as compared to that of the control. The larger the patch size, the greater the tendency that the number of large GGT (+) lesions will increase. These findings indicate that not only GGT (+) lesions but also the surrounding hepatocytes proliferate clonally.
札幌医科大学の論文
1988-06-01