Function and homeostasis of copper and zinc in mammals.

Recently there has been great interest in the determination of levels of trace elements in biological systems. The goals of many researchers in this field have been: understanding the roles of micronutrients in biochemical processes and the evaluation of biological mechanisms that maintain tissue concentrations at relatively constants levels. The biochemical and physiological functions of the micronutrients copper and zinc have been reviewed with emphasis on factors, both endogenous and exogenous, associated with the maintenance of homeostatic levels in mammalian sera. Understanding the mechanisms affecting homeostasis will provide a background necessary for the application of data on serum trace minerals in the diagnosis and prognosis of disease states. The general roles of copper and zinc in animal nutrition may be understood by evaluating physiologic changes associated with deficiency states of these essential elements. Deficiencies are associated with antagonisms and interactions from other elements and from chelating organic compounds as well as with primary deficiencies due to insufficient dietary levels. Biochemical and physiochemical properties of copper and zinc biomolecules are discussed with primary emphasis on the forms of these metals in serum. Also discussed in detail, are the effects of disease, radiation exposure and environmental factors on serum and tissue copper and zinc levels.