IN-VIVO MUCOSAL UPTAKE, MUCOSAL TRANSFER AND RETENTION OF IRON IN MICE

An improved and sensitive method for studying iron absorption in mice with alterations in body iron stores is described. Mice with varying i ron status were given a double isotope-labelled test dose containing F e-59 and Cr-51 as a non-absorbable indicator, via an oroesophageal nee dle. Using a whole-body counter it was possible to measure in vivo the initial mucosal iron uptake and long-term iron retention and to calcu late mucosal iron transfer. A significant difference was demonstrated between normal and both anaemic and dietary iron-loaded mice with rega rd to the various steps of iron absorption. When mice were tested twic e for iron absorption, the results were highly reproducible. In conjun ction with other parameters, the method described is useful in studyin g the mechanism and the regulation of iron absorption in mice.