Abstract
Considering the results of our previous experiment, another animal experiment using rats was carried out to elucidate the interaction of Cd and Zn on the ac-cumulation of some metals in tissues and to clarify the protective effects of Zn on the ceronic toxicity of Cd. The animals were divided into 4 groups. The diet for Group I was added 50 ppm of Cd, that for Group II was added 50 ppm of Zn and that for Group III was added 50 ppm of Cd and 50 ppm of Zn. Group IV was the control group. One-half of the animals in each group were killed after 14 weeks of exposure and the other half after 28 weeks of exposure. In both cases, several metals in the tissues were analyzed. Conclusions derived from the results of this experiment are as follows: 1) Cd accumulation in the kidney and the liver is not influenced by the simultaneous administration of Zn, 2) Zn increases in the liver by Cd administration, 3) Cd intake also enhances Cu level in the tissues, 4) Zn prevents anemia caused by Cd exposure, 5) no differences are found in Ca concen-trations in the femur among the groups, and 6) significant histopathological changes of the kidneys are not observed among the exposed animals.
