ラット大腿骨中カルシウム量におよぼすカドミウム, 鉛および亜鉛の相互作用について

抄録

To investigate the effect of heavy metals on bone metabolism, cadmium acetate, lead acetate, and zinc acetate (0.89μmol as metal ion/100 g body weight) were intraperitoneally administered to rats 5 times every other day, and animals were bled 2 days after the last administration. The amount of metals that accumulated in the bone was about the same in the diaphysis and epiphysis of femur, and the amount of zinc was the largest, followed by lead, and that of cadmium was slight. This phenomenon was also observed after the administration of combined metals. The serum calcium concentration decreased significantly by the administration of cadmium or lead, compared with that of control, while it was not changed by zinc. The serum inorganic phosphorus concentration lowered significantly by the administration of cadmium, but increased slightly by lead and was not changed by zinc. The bone calcium concentration after cadmium administration decreased significantly in the epiphysis of femur but did not change in the diaphysis, compared with that of control. Lead administration markedly decreased the bone calcium concentration in both diaphysis and epiphysis of femur, white zinc administration increased it significantly in two parts of femur. Reduction of calcium concentration in the epiphysis caused by cadmium or lead administration was inhibited significantly by the administration of the combined cadmium, lead, and zinc. These results suggest that the effect of heavy metals on bone calcium appears specifically in response to the species of the metal, and that the specific action of each metal was modified by the administration of these metals in combination.