CADMIUM STIMULATION OF GLYCOSAMINOGLYCAN SYNTHESIS BY CULTURED VASCULAR ENDOTHELIAL-CELLS - COMPARISON OF VARIOUS CELL-TYPES

We investigated the effect of cadmium on the synthesis of glycosaminog lycans (GAGs) in confluent cultures of vascular endothelial cells deri ved from bovine aorta. Cadmium markedly increased the incorporation of [H-3]glucosamine into GAGs in both the cell layer and the conditioned medium but decreased [S-35]sulfate in the cell layer. This suggested that cadmium induced the GAG synthesis by endothelial cells accompanie d by a reduction of the sulfation of cell-associated GAGs. Of the test ed heavy metals, the [S-35]sulfate incorporation in the cell layer was significantly decreased by lead; zinc slightly but significantly incr eased the [S-35]sulfate incorporation; manganese and copper failed to change the [H-3]glucosamine and [S-35]sulfate incorporation; and the i ncorporation of [H-3]glucosamine was increased only by cadmium. On the other hand, vascular smooth-muscle cells and fibroblastic Balb/3T3 ce lls responded to cadmium in a way similar to vascular endothelial cell s, while fibroblastic IMR-90 cells, Chang liver cells and epithelial L LC-PK1 cells altered the [H-3]glucosamine and [S-35]sulfate incorporat ion after exposure to cadmium in different manners. The alteration of GAGs induced by cadmium may be involved in the pathogenesis of the met al.