Histochemical localization of copper in the intestine and kidney of macular mice: light and electron microscopic study.

Menkes' disease is an X-linked recessive disorder characterized by accumulation of copper in various organs and cells, such as the intestine, kidney, and cultured fibroblasts. Light and electron microscopic localization of Cu was investigated in the intestine and kidney of macular mice, an animal model of Menkes' disease, by a modified sulfide-silver method. Cu was accumulated in the cytoplasm of the absorptive epithelial cells, the vascular endothelium, and secretory granules of the Paneth cells. In kidney the distal tubule cells and glomeruli of both macular and control mice stained faintly, whereas the organelle-free cytoplasm in the proximal tubule cells of macular mice stained more intensely than those of controls. The nuclei, mitochondria, and lysosomes of the cells of macular mice hardly stained at all. These findings indicate that Cu is concentrated in the organelle-free cytoplasm of the affected cells of macular mice. This suggests that the Menkes' mutation affects Cu transport from the cytosol to the organelles in the cell.