Arsenic-copper interaction in the kidney of the rat

1. The interaction between As and three toxic metals (Cd, Ni and Pb) and Cu (an essential trace metal) in the kidney was investigated in the rat by feeding diets containing various concentrations of As whilst maintaining constant concentrations of the other elements. After 1, 3, 7 and 15 weeks of feeding, metal contents in the renal cortex and medulla, red blood cells and plasma were determined by atomic emission spectrometry (ICP-AES). 2. As accumulated in the whole kidney, whereas Cu accumulated only in the cortex. Accumulation of Cu was found to depend on the feeding period and dietary As concentration. 3. As was also accumulated in red blood cells, where saturation was found at 550 micrograms As g-1 cells. 4. Although Cd was also accumulated in the cortex, its accumulation was independent of the dietary As concentration. Ni and Pb were not detected by ICP-AES. 5. Chromatography of the supernatants from cortical homogenates of control and As-treated rat kidney suggested that Cu accumulated in renal metallothionein (MT). Its accumulation in this fraction was independent of that of Cd, indicating that the As-Cu interaction was not a result of MT induction, but rather that it might result from altered renal handling of Cu with subsequent incorporation into MT.