Distribution of 59Fe-labelled iron-poly(soribitol-gluconic acid) complex in normal and anaemic rats

An iron carbohydrate complex, iron-poly(sorbitol-gluconic acid), Ferastral, was labelled with 59Fe, and its distribution in rats was studied. The animals were intramuscularly treated with a dose of 10 mg of iron/kg. Three groups of animals were used: group A: non-anaemic and group B: anaemic rats, both kept on iron-deficient diet, and group C: non-anaemic rats kept on iron-supplemented diet. Urinary and faecal excretion, distribution in the body and incorporation in blood of the 59Fe was followed up to 28 days. The total excretion after that time was 15%. There was a rapid initial phase followed by a slower continuous one. After 28 days group A had 25, group B 13 and group C 40% of the given dose remaining at the site of injection. The corresponding values in liver after 28 days were 7, 4 and 17% of the given dose, respectively. In blood a continuous increase was observed. At 28 days after administration 26, 43 and 17% of the given dose had been incorporated in the red blood corpuscles of the respective groups. These results show that the iron complex is absorbed from the site of injection and is utilized for haemoglobin synthesis. They also show that the disposition of the complex is influenced by the iron content of the diet.