Studies on the partition of transferrin-donated iron in rabbit reticulocytes. I. The kinetics of iron distribution between stroma and cytosol.

The distribution of transferrin-donated iron between the stroma and cytosol compartments of rabbit reticulocytes was studied. In cells with inhibited haem synthesis iron accumulates in the stroma fraction. The stromal accumulation of iron was found to be reversible and dependent on the coupled state of mitochondrial respiration. Iron in cytosol, however, proved to be more available for haem synthesis than iron accumulated in stroma. A hypothesis concerning mitochondrial iron uptake is proposed, by which the experimental and pathological changes in the intracellular distribution of iron can be explained.