DOSE-RELATED EFFECTS OF DIETARY IRON SUPPLEMENTATION IN PRODUCING HEPATIC IRON OVERLOAD IN RATS

The influence of varying the level of supplemental dietary iron on the development of hepatic iron overload was examined in rats. Two days a fter giving birth, Porton rats were fed a diet supplemented with 0, 0. 5, 1 or 2% carbonyl iron, to institute dietary iron supplementation to the young via breast milk. After weaning, the offspring continued to receive the assigned diet until 32 weeks of age. Liver biopsies were t aken from some rats at 8, 16 and 24 weeks of age and from all rats at 32 weeks of age, for assessment of iron overload. For both male and fe male rats, hepatic iron content was increased in a dose-related manner by feeding supplemented diet. Hepatic iron content of male rats tende d to reach a plateau after 8-16 weeks of supplementation, while that o f female rats continued to rise throughout: the experimental period, s uch that the hepatic iron content of female rats was 2.8-fold that of similarly treated males at 32 weeks of age. Iron supplementation was a ssociated with only moderate retardation of growth. By choosing an app ropriate level of iron supplementation, good (grade III-IV) hepatic ir on loading can be achieved with minimal adverse effects on the animals ' overall health.