Interaction of metal ions with cadmium‐induced cellular toxicity

Abstract

Interactions between Cd and other metal ions are important from nutritional and toxicological aspects. Cd is toxic to isolated rat hepatocytes. These cells can be used to investigate effects of other metals on Cd-induced cellular injury. Isolated hepatocytes were incubated at 37.degree. C with vehicle (saline); Cd (200 or 400 .mu.M); or Cd plus Cr, Mn, Zn, Ni, Pb, Se or Fe (200-1000 .mu.M). Evidence of cellular injury was assessed by loss of intracellular K+ and aspartate aminotransferase from hepatocytes. Effects on lipid peroxidation, as measured by concentration of thiobarbituric acid reactants, were assessed. Uptake of 109Cd and interaction of the other metal ions with this accumulation were also quantitated. Cell injury due to Cd was reduced by Cr, Mn, Zn, Pb and Fe. Lipid peroxidation due to Cd was inhibited by Cr, Mn and Zn. All metals except Ni produced increased amount of Cd accumulated by hepatocytes. There was no consistent relation between reduction of cellular toxicity and lipid peroxidation inhibition or Cd uptake. Protective properties of some metals seen in vivo could be demonstrated at cellular level. Protective effects of metals on Cd-induced cellular toxicity were not due to decreased Cd uptake or lipid peroxidation.