Renal effects of repeated administration of calcium disodium ethylenediaminetetraacetate during excessive exposure to lead in rats.

The renal effects of repeated administration of EDTA were studied in rats given 0.5% lead as lead acetate in drinking water for 24 weeks. Repeated treatment of lead toxic rats with EDTA during continuous exposure to lead reduced blood lead levels and brain and bone lead but not to a statistically significant level (p greater than 0.05). Liver lead concentration in the EDTA treated, lead exposed rats changed only slightly upward, but kidney lead levels decreased greatly when compared to lead exposed, non-EDTA treated rats, (group IV vs. group III), (p less than 0.05). Light and electron microscopy of kidneys of lead treated rats showed evidence of an early interstitial nephropathy characterized by peritubular fibrosis and variation in size of tubular cells. Nuclei of renal tubular cells of lead exposed rats had inclusion bodies, but these were not present in lead exposed, EDTA treated rats. The present study suggests that repeated treatment of rats with EDTA during continuous exposure to lead reduces renal lead concentration but does not significantly influence the progression of lead induced nephropathy.