J. Biol. Chem., Vol. 261, Issue 18, 8298-8302, Jun, 1986
Amines as inhibitors of iron transport in rabbit reticulocytes
J Glass and MT Nunez
The effect of the known inhibitors of iron uptake, n-butylamine and NH4Cl,
was examined at the molecular level to more precisely define the mechanisms
by which these lysosomotropic agents block iron uptake by rabbit
reticulocytes. Utilizing a rapid pulse-chase technique to follow the
handling of a cohort of 59Fe, 125I-transferrin bound to rabbit
reticulocytes, both amines were observed to have no effect on the cell-
mediated release of 59Fe from internalized transferrin. The results
indicated, however, that both agents acted to 1) retard the internalization
of transferrin bound to transferrin receptors on the plasma membrane of
reticulocytes, 2) retard the externalization of internalized transferrin,
and 3) block the transport into the cytosol of iron released from
transferrin.