Myoglobin and cytochrome response during repair of iron deficiency in the rat.

Abstract

The treatment of dietary Fe deficiency in the rat resulted in rates of tissue cytochrome c and myoglobulin repair that differed markedly from the rate of increase in concentration of hemoglobin. After initiation of oral supplementation, cytochrome c in intestinal mucosa returned to control concentrations within 2 days compared to the 8 days required for the correction of anemia. Cytochrome c and myoglobin deficiencies in skeletal muscle persisted even after hemoglobin concentrations had returned to normal. Normal concentrations were not observed until 40 days after initiation of oral ferrous sulfate. These divergent rates of repair of heme protein parallel known rates of cell renewal within these tissues in the normal rat. The repair of cytochrome oxidase deficiency in the intestinal mucosa appeared to proceed from the crypts and extended about halfway toward the tips of the villi within 24 hours of either oral or intramuscular Fe administration. These findings suggest that the restitution of cytochrome oxidase activity is limited by the production of new mucosal cells. Fe repletion after a 15-day period of Fe deprivation resulted in a more rapid correction of skeletal muscle myoglobin and cytochrome c deficiencies than was observed after a 35-day period of this diet.