Metabolic Effects of Molybdenum Toxicity in the Rat

Abstract

The influence of high dietary intakes of molybdenum on certain enzyme systems of rat liver and kidney has been studied with particular reference to systems known to be concerned with the metabolism of sulfur compounds. The activity of liver sulfide oxidase was found to be markedly depressed in molybdenum toxicity. High molybdenum intakes had apparently no effect on the activity of liver cysteine desulfhydrase, on kidney aryl sulfatase or on the oxidation of L-cysteine sulfinate by liver homogenates. Indications that molybdenum toxicosis may be accompanied by a derangement of protein metabolism were obtained during these studies. Under the conditions of these experiments in which a relatively high copper intake was maintained, no evidence was obtained to suggest that the limitations to growth imposed by molybdenum toxicosis in the rat could be directly attributed to changes in the activity of enzyme systems normally sensitive to restrictions in the supply of physiologically available copper.