CHANGES IN BIOCHEMICAL INDICATORS OF IRON STATUS DURING IRON REPLETION AND DEPLETION IN MONKEYS

Different modes of iron depletion and repletion were studied in monkey s to understand the sequential changes in and the relative importance of different biochemical indicators of iron status. Six control monkey s were divided into two groups, one was fed an iron-deficient diet (gr oup 1) and the other underwent phlebotomy in addition to receiving an iron-deficient diet (group 2). Previously iron-depleted monkeys were s ubdivided into 4 groups of 3 animals each. While one group was continu ed on the iron-deficient diet (group 3), the second group received par enteral iron (group 4), the third group (group 5) received a sufficien t-iron-containing diet, and the fourth group was fed 50% of the iron r equirement. All indicators of iron status like hemoglobin (Hb), erythr ocyte protoporphyrin (EPP), serum transferrin saturation and serum fer ritin were monitored periodically, in addition to liver and bone marro w iron. All the indicators except serum ferritin and liver iron showed a decrease in group 2, On the other hand, animals receiving parentera l iron (group 4) showed an increase in all the parameters except serum ferritin. The dietary supplementation produced an increase in Hb and a decrease in EPP only (groups 5 and 6). There was a significant posit ive correlation between changes in bone marrow iron and Hb concentrati on depending on the severity of depletion and repletion. Both serum fe rritin and liver iron did not respond to changes in dietary iron. Anot her parameter which responded to repletion was EPP. Serum ferritin and liver iron did not respond to changes in dietary iron or was not sens itive to subclinical iron deficiency. The results indicate that change in Hb is more sensitive to detect the deficiency of iron. It was also observed that different parameters respond variably under different m odes of depletion and repletion.