AJP - Gastrointestinal and Liver Physiology, Vol 244, Issue 2 138-G144, Copyright © 1983 by American Physiological Society
Effect of iron stores on hepatic metabolism of transferrin-bound iron
J. W. Wilms and R. G. Batey
Hepatic and splenic accumulation and hepatic subcellular distribution of
iron from a tracer dose of purified 59Fe-labeled transferrin were studied
in normal, iron-deficient, iron-loaded, and pregnant rats. Hepatic and
splenic 59Fe content was determined at varying intervals and the
subcellular distribution then studied. In normal rats hepatic accumulation
of 59Fe was biphasic with 9-10% of the dose present in the liver in the
first 2 h postinjection, followed by a plateau of 4 h and a second rise to
20-25% at 16-18 h. During iron deficiency, 5-6% of the dose accumulated in
the liver in 2 h and remained at this level. Iron loading resulted in a
rapid accumulation of 17% of the dose at 6 h, and the normal plateau was
absent. Splenic iron accumulation was similar in the normal and iron-loaded
groups with approximately 3% of the dose present in the spleen over the
7-day study. Iron deficiency resulted in a threefold increase in splenic
iron content to 10% of the dose at 1 h postinjection. Hepatic and splenic
iron accumulation was markedly depressed in the pregnant group. Subcellular
distribution studies showed that the 59Fe moved rapidly into ferritin in
all groups and was not at any time associated with either lysosomes or
mitochondria. These studies present further physiological data of the
effects of differing iron states on hepatic and splenic iron accumulation.
