Control of iron absorption.

Intestinal iron absorption plays an essential role in body iron homeostasis, although the mechanism by which iron moves across the cells of the intestinal epithelium and the way in which this process is regulated are poorly understood. Signals to alter iron absorption are received from the body by cells of the intestinal crypt and these signals are translated into an absorption response after the cells have migrated up the villus and differentiated into mature absorptive enterocytes. The intracellular iron concentration of the crypt cell may play an important role in the regulation of this process. Biochemical investigations on the mechanism of iron absorption have met with only limited success and a molecular understanding of this mechanism appears most likely to come from the identification of the genes affected in various inherited disturbances of iron absorption in several mammalian species.