Iron Metabolism: The Regulation of Intestinal Absorption of Iron and Metabolic Effects of Iron Deficiency.

Studies were performed in an attempt to elucidate 1 the mechanism regulating absorption of iron and 2 the systemic manifestation of iron deficiency. The transfer of iron from the intestinal epithelial cell to the plasma appears, in part, to be regulated by the iron binding capacity of transferrin. The addition of transferrin to a viable suspension of rat intestinal epithelial cells results in the removal of cellular iron. The amount removed is related to the unsaturated iron binding capacity. The affinity of this molecule for the membrane is inversely proportional to the iron saturation of the transferrin molecule. Iron deficiency is a systemic disorder which results in the depletion of many essential iron containing enzymes throughout the body as well as a decrease in hemoglobin production. Iron deficiency in infants and growing dogs produces metabolic abnormalities in the intestinal epithelial cells that result in a malabsorption syndrome. In addition, iron deficient red cells have increased susceptibility to hemolysis with the membrane sulhydryl inhibitor, P-mecruribenzoate. Total SH groups in the membranes of iron deficient cells are reduced. The end result is an inability to protect membrane SH groups from oxidation which may lead to increased cell rigidity and loss of membrane.