摘要：In order to investigate the effects of zinc on the contents of collagen and mineral in bone, femurs obtained from 9-day-old chick embryo were cultivated for 6 days in the presence of 58, 139 or 580μM ZnCl2. Decreases in the contents of mineral and collagen were caused by zinc concentrations of 193μM and above. Zinc inhibited incorporation of 45Ca into bone. Release of 45Ca from bone was slightly inhibited by zinc. Zinc was shown to have an inhibitory effect on bone formation rather than on bone resorption. On the other hand, 27, 54 or 108μM zinc prevented a decrease in collagen content caused by cadmium, though zinc did not prevent a decrease in mineral content caused by cadmium. Cytosol obtained from zinc-treated bones was found to contain metallothionein-like protein, which might participate in zinc-induced tolerance to cadmium toxicity. These results indicate that the coexistence ef zinc at low concentrations with cadminm lowered bone mineral content but did not affect the matrix.
关键词：zinc;cadmium;embryonic chick bone;^ Ca release;collagen;mineralization;metallothionein-like protein;bone formation
