# name
Basis of plasma iron exchange in the rabbit

# metadata.dc.description.abstract[].value
Rabbit transferrin in vitro is shown to
load ferrous iron at random on its specific binding sites.
The release of iron to reticulocytes is shown to be an
all-or-none phenomenon. The two monoferric transferrins
have similar in vivo plasma iron clearance rates
and tissue distribution. Diferric transferrin, while giving
a similar tissue distribution of radioiron, has a
plasma iron clearance rate approximately twice that
of the monoferric transferrins at low plasma iron concentrations.
This difference diminishes as the plasma
iron concentration increases. These results are consistent
with a progressively greater in vivo conversion of
mono- to diferric transferrin as transferrin saturation
increases. The in vivo plasma iron turnover in the rabbit
increases progressively as the plasma iron increases,
from a mean value of -0.8 mg/dl whole blood per
d at a plasma iron concentration of 50 ug/dl to 2.0 at
a plasma iron concentration of 300.
The molecular behavior of transferrin and its iron
over this range was investigated using '251-transferrin,
[55Fe]monoferric transferrin, and [59Fe]diferric transferrin.
The equilibrium distribution of transferrin between
its apo-, mono-, and diferric moieties was similar
to that predicted on the basis of the percent saturation
and random distribution. Rate constants of
iron loading and unloading calculated from the percent
saturation and from the clearance rates of [55Fe]-
monoferric and [59Fe]diferric transferrin were similar
to those derived from changes in injected '251-apotransferrin.
On the basis of these data, it is concluded
that the plasma transferrin pool is nonhomogeneous
and that the relative size of the mono- and diferric
cycles depends on transferrin saturation. A formula is
proposed for correcting the plasma iron turnover,
thereby eliminating the effect of plasma iron concentration,
so as to reflect directly the number of tissue
transferrin receptors.

# metadata.dc.publisher[].value
American Society for Clinical Investigation

# metadata.dc.relation.ispartof[].value
Journal of Clinical Investigation, 1982, vol. 70, núm. 4, p. 769-779.

# metadata.dc.rights[].value
(c) The American Society for Clinical Investigation, 1982

# metadata.dc.source[].value
Articles publicats en revistes (Biologia Cel·lular, Fisiologia i Immunologia)

# metadata.dc.title[].value
Basis of plasma iron exchange in the rabbit