1998 Volume 15 Pages 141-145
Long-Evans Cinnamon (LEC) rats develop spontaneous hepatic injury. We obtained evidence which shows unusual accumulation of copper (Cu) in the livers of LEC rats, followed by the finding of copper-metallothionein (Cu-MT) induction. On the other hand, Ebara et al. have found that copper is accumulated in the human liver suffered from hepatoma. Thus, we measured MT and 4 metals (Cu, Zn, Fe, and Mn) and compared the Cu-MT levels in the livers of LEC rats and human suffered from hepatoma. The levels of MT and Cu in the LEC rat liver remarkably increased with age. The MT levels in human liver were evaluated as logarithmic concentration ratio [log ((concentration in tumor site) / (concentration in juxta-tumorsite))] was decreased with the tumor size, but no changes in the Cu levels were found. Then, we separated the MT in human livers by gel filtration on Superose 12. In tumor site of the human liver, MT was determined as Cu-MT, whereas in juxta-tumor site, the presence of Cu, Zn-MT was suggested. These results indicate that MT is induced as Cu-MT in the early stage of hepatoma, but it decreases in the development of hepatoma. Thus, we conclude that the development of hepatoma in LEC rats and human might be understood with respect of the induction of Cu-MT but both rates for the formation and degradation of MT are different between LEC rat and human hepatoma.
