High arsenic intake raises kidney copper and lowers plasma copper concentrations in rats

The effect of high arsenic intake on copper metabolism was investigated. Ma le rats aged 6 wk had free access to purified diets containing either 0 or 100 mg As/kg diet and demineralized water for a period of 2 wk. Arsenic was added to the diet in the form of NaAsO2. The high-arsenic diet decreased f eed and water intake and body weight gain, but significantly increased live r weight. Kidney weight was not affected. Arsenic feeding drastically eleva ted kidney copper concentration, but significantly reduced copper concentra tion in plasma. Both true absorption and biliary excretion of copper were d ecreased significantly in rats fed the high-arsenic diet. True copper absor ption was lowered essentially through the lower copper intake in the rats f ed arsenic. It is speculated that arsenic feeding primarily leads to copper accumulation in the kidney, followed by a decrease in feed intake and thus in true, absolute copper absorption, a decrease in plasma copper concentra tion, and a decrease in biliary copper excretion.