1. Intestinal absorption of iron
Intestinal absorption of iron. Fe3+ is converted to Fe2+ by the ferric reductase DCYTB, and Fe2+ is transported into the enterocyte by the apical membrane iron transporter DMT1. Heme is transported into the enterocyte by a separate heme transporter (most likely heme carrier protein 1, HCP1), and heme oxygenase-2 (HO2) releases Fe2+ from the heme. Some of the intracellular Fe2+ is converted to Fe3+ and bound to ferritin. The rest binds to the basolateral Fe2+ transporter ferroportin-1 (FPN1) and is transported to the interstitial fluid. The transport is aided by hephaestin (Heph) which converts Fe2+ to Fe3+. In plasma, Fe3+ is transported bound to the iron transport protein transferrin (TF).
Source: Digestion, Absorption, & Nutritional Principles, Ganong’s Review of Medical Physiology, 25e
Citation: Barrett KE, Barman SM, Boitano S, Brooks HL. Ganong’s Review of Medical Physiology, 25e; 2016 Available at: Accessed: October 19, 2017
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