Zinc protection against cadmium-induced destruction of the monolayer of cultured vascular endothelial cells.

The effect of zinc on the destruction of vascular endothelial cell monolayer caused by cadmium was investigated using bovine aortic endothelial cells in a culture system. It was histologically revealed that cadmium-induced de-endothelialized area formation was markedly prevented by zinc. Zinc prevented cadmium-induced detachment of [3H]thymidine-labeled endothelial cells from the monolayer. Although cadmium increased the activity of lactate dehydrogenase in the medium, a marker of nonspecific cell damage, zinc markedly suppressed it. On the other hand, zinc significantly prevented cadmium-induced decrease in the incorporation of [3H]thymidine into the acid-insoluble fraction of the growing cells. From these results, it was suggested that impairment of the endothelial cell monolayer caused by cadmium is protected by zinc; this protection was postulated to be due to both a reduction of the cell detachment caused by cadmium-induced nonspecific cell damage and a decrease in cadmium inhibition of the cell proliferation which would help the repair of de-endothelialized areas.