Cytosolic levels and distribution of cadmium, copper and zinc in pretumorous livers from diethylnitrosamine-exposed mice and in non-cancerous kidneys cancer patients.

Exposure of mice to diethylnitrosamine (DEN) in their drinking water, resulted in decreases of Cu and Zn in cytosol of both pretumorous and tumorous liver tissue. Copper was reduced 28% and zinc 44.5% in cytosol of tumorous tissue at the time of death. Analysis of Sephadex G-75 gel chromatography profiles revealed that these decreases were mainly from the high molecular weight protein pool, with smaller decreases from metallothionein. Exposure of mice to Cd in their drinking water resulted in the accumulation of most Cd on metallothionein with a smaller accumulation in the high molecular weight protein pool; Cu and Zn levels were increased in both of these cytosolic pools. When DEN was administered with Cd, there were smaller increases of Cu and Zn, and more Cd accumulated in the high molecular weight protein pool. In non-cancerous kidney of postmortem cancer patients, most Cd appeared in the high molecular weight protein pool, whereas in controls, most appeared on metallothionein.