Zinc Reduces the Inhibitory Effect of Cadmium on the Proliferation of Bovine Corneal Endothelial Cells In Vitro

Abstract

Cadmium chloride at 0.25 µg/ml inhibited the proliferation of bovine cor-neal endothelial cells in vitro 24 hr after treatment during the preconfluent stage. The growth curve was significantly lowered with a slight increase in nuclei/mm² after 1 week. The cadmium-treated cells at 120 hr became elongated and spindle-shaped. This morphologic change was more conspicuous at 168 hr. When cadmium-treated cells were treated simultaneously with 0.25 or 1 µg/ml zinc chloride, their growth curves were significantly elevated, which suggests that zinc reduces cadmium toxicity on this cell type. At 168 hr, however, these zinc-ameliorated cells were morphologically different from the control cells and the growth curves were statistically lower than the control. The present results suggest that the preconfluent model of bovine corneal endothelial cells can be used as a sensitive toxicity evaluation test based on changes in the growth curve of the cells.