Quantification of metallothionein on the liver and kidney of rats by subchronic lead and cadmium in combination

• Investigated the hazard of environmentally relevant, low-dose exposure to a particular mixture compound.
• An equitoxic mixture ratio design was applied in as an animal model of Pb/Cd-induced subchronic toxicological evaluation.
• Determined the additive effects with quantification of metallothioneinon the liver and kidney of rats by subchronic lead and cadmium in combination.

The combined subchronic effects of exposure to lead acetate and cadmium chloride on oxidative stress and metallothionein (MT) gene expression were detected in the liver and kidney of rats to investigate the hazards of environmentally relevant, low-dose exposure to these compounds. Pb and Cd co-induced oxidative stress in liver and kidney tissues. This result was indicated by a significant (P < 0.01) increase in the maleic dialdehyde level and decreased levels of reduced glutathione, superoxide dismutase, catalase, and glutathione peroxidase. MT mRNA and protein significantly increased (P < 0.01) in the liver and kidney of rats. Furthermore, the expression levels of MT-1 mRNA and MT-2 mRNA differed between the liver and kidney. The findings indicate that Pb combined with Cd induced oxidative damage in the liver and kidney of rats, and MT may be a biochemical environmental indicator.