IRON STATUS, BLOOD-LIPIDS AND ENDOGENOUS ANTIOXIDANTS IN RESPONSE TO DIETARY IRON LEVELS IN MALE AND FEMALE RATS

The effect of dietary iron levels on iron status, blood lipids and end ogenous antioxidants was investigated in male and female rats. Diets l ow in iron (15 mg/kg Fe; LFe) or high in iron (400 mg/kg Fe; HFe) were given to groups of male (n=6) and female (n=6) weanling rats for six weeks. In a second experiment the same dietary iron levels were fed to groups (n=12) of males and females for seven months, during which col on tumours were induced. Indices of iron status, blood lipid levels an d antioxidant enzyme activities were measured in both experiments. In the first experiment, indices of iron status were significantly higher in HFe rats and in females compared with males. Cholesterol and trigl ycerides were significantly higher in HFe rats and cholesterol was sig nificantly higher in males. Plasma albumin and bilirubin levels and pl asma caeruloplasmin activity were significantly higher in female rats. The second experiment confirmed the higher indices of iron status in HFe rats and in female rats, and also showed that plasma cholesterol l evels were significantly higher in HFe rats. There were no consistent, significant differences over both experiments in activities of the an tioxidant enzymes measured. Results show that higher dietary iron leve ls are associated with higher cholesterol levels in male and female ra ts. However cholesterol was found to be higher in male rats while iron status was higher in female rats. This indicates that factors other t han iron status are responsible for the differences in cholesterol in male and female rats.