細胞培養法を応用した重金属の臓器毒性に関する基礎的研究

抄録

To elucidate the possible toxicity of heavy metals in a renal tubular epithelial cell line derived from a normal cynomolgus female monkey (JTC-12. P3 (F) ), the effects of HgCl₂, Na₂CrO₄ and NiCl₂ on the dome formation and the release of intrinsic enzymes from the cells were studied. The results were as follows:
1. The JTC-12. P3 (F) cells showed an evident dome formation when an inducer of differentiation (hexamethylene bisacetamide or N, N-dimethylformamide) was added to the medium.
2. Ouabain inhibited the dome formation of the JTC-12. P3 (F) cells, suggesting that the dome formation is dependent on the active transepithelial transport of Na⁺.
3. The addition of 40μM HgCl₂, 10μM Na₂CrO₄ or 20μM NiCl₂ inhibited the dome formation. 40μM HgCl₂, 10μM Na₂CrO₄ or 150μM NiCl₂ caused significant cell death.
4. The addition of 5μM HgCl₂, 1μM Na₂CrO₄ or 20μM NiCl₂ resulted in an increased release of lactate dehydrogenase into the medium for 6 hours. 20μM HgCl₂, 1μM Na₂CrO₄ or 20μM NiCl₂ increased the medium γ-glutamyl transpeptidase concentration for 6 hours, but 40μM HgCl₂, 5μM Na₂CrO₄ or 100μM NiCl₂ did not cause a significant increase in the medium alkaline phosphatase concentration.
The results suggest that the JTC-12. P3 (F) cells possess, at least in part, functional characteristics similar to the other kidney proximal tubular cells and that the inhibition of dome formation and enzyme release from the cells may be the early indicators that predict metal toxicity to the cells.