Calcium ethylenediaminetetraacetate toxicity in the rat: ultrastructural effects on skin collagen.

The effect of calcium ethylenediaminetetraacetate (CaEDTA) i.v. infusion on skin ultrastructure was studied in the rat with the aid of transmission electron microscopy. High magnification electron micrographs of collagen fibrils were analysed with a computer aided image analyser, in terms of the Gaussian distribution of fibril diameter and the distance between cross striations of collagen fibrils (D-spacing). CaEDTA caused marked depletion of collagen fibrils in the skin. The collagen fibrils from CaEDTA treated rats exhibited significant increases in D-spacing (about 30%) and diameter (about 40%) compared to saline treated controls. These findings are consistent with earlier published biochemical data indicating that CaEDTA enhances collagen degradation in the rat.