Effect of the Copper Status of the Rat on the Copper-Molybdenum-Sulfate Interaction

Abstract

The effect of the copper status and dietary copper intake of the animal on its response to molybdenum and sulfate was studied. When the rat's copper stores were low and a copper-deficient diet was fed, small amounts of molybdenum produced toxic symptoms which were intensified by the simultaneous addition of sulfate. However, when the copper stores and dietary copper intake were adequate, larger amounts of molybdenum were required to produce molybdenosis, and sulfate completely prevented the harmful effects of molybdenum. In the first instance, the copper deficiency syndrome was evident and dietary copper prevented all toxicity symptoms. In the second case, the corrective effect of copper was negligible, but sulfate prevented the marked growth retardation produced by molybdenum. These observations are discussed in relation to several hypotheses concerned with the molybdenum-copper-sulfate interaction. An analysis of the liver-copper stores of these animals revealed that the suggested direct relationship between copper intake and copper storage in the liver does not always obtain. The copper status of the animal and the dietary levels of molybdenum and sulfate, as well as copper, significantly influence the level of copper in the liver.