2002 年 48 巻 6 号 p. 461-466
In order to determine the interrelationship between dietary iron and zinc levels, the effects of dietary iron levels (2, 10, 20, and 40μg/g) on changes in iron and zinc status and zinc enzyme activities (aminolevulinic acid dehydratase ALA-D EC 4. 2. 1. 24 and alkaline phosphatase ALK-P EC 3. 1. 3. 1) in male Wistar rats were investigated using adequate and marginally deficient zinc diets (2 5 and 5μg/g). When rats were fed 5μg., Zn/g diets, body weight gain and food intake remained unchanged at a Fe diet intake of 20μg/g or greater. Similar tendencies were obtained for hemoglobin, hematocrit, plasma iron, and transferrin saturation. In contrast, liver, spleen, and femur iron concentrations increased gradually with increased iron intake. Feeding diets containing 25μg Zn/g did not alter these parameters. The percentages of apparent iron absorption in both dietary zinc groups tended to increase with decreasing dietary iron and attained maximum levels at an Fe intake of 10μg/g. However, in the case of rats fed Fe at concentrations of 2μg/g iron absorp-tion decreased. Regardless of the dietary zinc level, rats fed diets with an Fe concentration of 2μg/g had decreased zinc absorption and plasma ALK-P activity. However, ALA-D activity was not influenced by dietary iron.
