Plasma Zinc and Leukocyte Changes in Weanling and Pregnant Rats during Zinc Deficiency

Abstract

The rate at which Zn became limiting in rats during dietary Zn deficiency was studied. Plasma Zn and leukocyte levels were measured at increasing stages of deficiency in pregnant female and growing male rats. After receiving a deficient diet for only 1 day, plasma Zn decreased by 38% in the pregnant animals and by 55% in the weanling males. Thereafter, the decrease became progressively less marked and reached a plateau by about 7 days in both groups. Longer periods of Zn depletion (21 days) increased the ratio of polymorphonuclear leukocytes to lymphocytes in the blood by a factor of 10. General food restriction elicited a similar but less marked response in the pregnant females but not in the young males. The Zn deficiency had no effect upon the total leukocyte count or upon the concentration of Zn in these cells. The data suggest that rats are not able to mobilize their body Zn deposits adequately to accomodate for even a short period of dietary restriction.