Thejournal of Biological Chemistry

Incorporation of plasma-bound iron into ferritin of liver and spleen of the rat is a dynamic process which accounts for 10% of the iron which normally leaves the plasma. It involves the reaction of adenosine triphosphate and ascorbic acid with iron bound to a &globulin of the plasma, transferrin, and leads to the transfer of this iron to ferritin. Evidence for this mechanism has been obtained from studies with rat liver slices, homogenates, cell-free extracts, and purified compounds (1). The present study, which describes experiments with the intact animal, offers confirmation of our findings in vitro. Alterations in the extent of serum iron incorporation into ferritin of rat liver and spleen in vivo coincide with experimentally induced alterations in oxidative metabolism of these tissues, as measured by changes in content of ribonucleic and deoxyribonucleic acids and protein, and by changes in extent of oxidative phosphorylation by liver mitochondria. These alterations are taken as evidence of increased or decreased synthesis of adenosine triphosphate within the cell. The relationship of ascorbic acid to the incorporation reaction is demonstrated by an impairment of this reaction in the liver and spleen of the ascorbic acid-deficient guinea pk.