Serum levels of calcium, selenium, magnesium, phosphorus, chromium, copper and iron--their relation to zinc in rats with induced hypothyroidism.

There is an important relation between thyroid hormones and zinc. Establishment of low zinc levels in hypothyroidism and high levels in hyperthyroidism is a significant proof of this relation. The aim of the present study was to explore changes in serum levels of some elements and their relation to zinc in rats with hypothyroidism. Thirty adult male rats of Sprague-Dawley type were divided into 3 equal groups: group 1, control; group 2, sham-hypothyroidism group supplemented with 10 mg/kg serum physiologic i.p. for 4 weeks; and group 3, hypothyroidism group supplemented with 10 mg/kg propylthiouracil i.p. for 4 weeks. Blood samples were collected from all animals by decapitation and serum calcium, phosphorus, chromium, copper, iron, magnesium, selenium and zinc levels were analyzed using an atomic emission apparatus. Group 3 had lower calcium, selenium and zinc levels, and higher chromium, copper, iron and phosphorus levels (p < 0.01 all) relative to groups 1 and 2. Study parameters did not differ between groups 1 and 2. Results obtained in this study indicate that hypothyroidism leads to changes in serum levels of some elements in rats. These changes may be associated with reduced zinc levels in hypothyroidism.