Effect of Form of Iron on the Interaction Between Nickel and Iron in Rats: Growth and Blood Parameters

Abstract

In two fully-crossed, two factor, completely randomized designed experiments, female weanling rats were fed a basal diet (con taining about 10 ng of nickel and 2.3 ^.g of iron/g) supplemented with graded levels of nickel and iron. Iron was supplemented to the diet in experiment 1 at levels of 0, 25, 50 and 100 jug/g as a mixture of 40% FeSO4-nHaO and 60% Fe2(SO4):)-nH2O and in experiment 2 at levels of 0, 12.5, 25, 50and 100 ��g/g as Fe2(SO4)s-nH2O (92% of the salt was in the ferric form). In both experiments, nickel was supplemented to the diet at levels of 0, 5 and 50 /ig/g as NiCU• 3H2O. When ferric sulfate was fed, an interaction between nickel and iron affected the hematocrit, hemoglobin level and plasma alkaline phosphatase activity which did not occur when a mixture of ferric and ferrous sulfates was fed. Growth, hematocrit and hemoglobin level, but not plasma cholesterol, of rats fed ferric sulfate were affected by dietary nickel. The effect of dietary nickel on hematocrit and hemoglobin level was less obvious and on plasma cholesterol was significant when rats were fed ferric-ferrous sulfate. Hematocrits and hemoglobin levels were lower in nickel-deprived than in nickel-supplemented rats only when iron was supplemented at low levels as ferric sulfate. When iron was added to the diet at 100 �ig/g as ferric sulfate or at 25, 50 and 100 /�g/g as a ferric-ferrous sulfate mixture, dietary nickel had no obvious affect on hematocrits and hemoglobin levels. This suggests that nickel has a role in the absorption of the ferric ion. J. Nutr. 110: 965-973, 1980.