Copper-binding protein in acute copper poisoning

This paper presents a suicide case of copper sulfate ingestion. Post-mortem autopsy revealed mucous membrane necrosis of the esophagus and the stomach. Histological examination revealed centrilobular necrosis in the liver and renal insufficiency. The quantitative determination of copper, zinc and cadmium in various tissues showed that the copper concentrations in blood, liver, kidney and lung were 3.5-24-fold higher than those of the normal level, whereas zinc and cadmium concentrations were within normal range. Chromatographical patterns on Sephadex G-75 showed that most of the accumulated copper in the liver and kidney was bound to metallothionein (MT), a low molecular weight protein with high metal binding capacity which plays a role in the detoxification of heavy metals, while no copper bound to MT was found in the lung. These results suggest that the formation of Cu-induced MT in the liver and kidney occurred at the early stage in fatal acute copper poisoning.