Severe damage of cultured vascular endothelial cell monolayer after simultaneous exposure to cadmium and lead.

This study evaluates the toxicity of lead in the presence or absence of cadmium on the maintenance of a monolayer of cultured bovine aortic endothelial cells. It was histologically shown that lead at 50 microM or less induced a slight formation of de-endothelialized areas on the monolayer after a 24-h incubation. Although lead accumulated in endothelial cells in a dose-dependent manner, the cytotoxicity (evaluated by the [3H]adenine release assay) was not detected. However, cadmium (1.0 or 2.0 microM)-induced de-endothelialized areas on the monolayer was considerably larger in the presence of lead at 10 microM; the cytotoxicity of cadmium was significantly enhanced by lead. It was concluded that vascular endothelial cell monolayer is severely destroyed by a greater cytotoxicity of combination of cadmium with lead.