Variations in metallothionein, Zn, Cu, and Fe concentrations and ceruloplasmin activity in pregnant rat dams and their fetuses

Growing rat fetuses have great need for Zn, Cu, and Fe. In fetal livers (FL) large accumulations of Zn and Cu connected with increased metallothionein (MT) synthesis take place. In dams, serum changes in metals concentrations with increased ceruloplasmin (Cp) activity are observed. The aim of this study was to determine (1) mutual relationships in the accumulation of MT, Zn, Cu, and Fe in fetal livers; (2) changes in Zn, Cu, and Fe concentrations in dam serum; and (3) the day with the maximum Cp activity. Sections of rat dams were taken on 16th-21st day of gestation, twice a day, and MT, Zn, Cu, and Fe concentrations in liver, spleen, kidneys, and placenta of dams and in liver and brain in fetuses were determined. In fetal livers high correlations between MT and Zn and between Zn and Cu were obtained. The investigated Cp activity was always high, reaching its maximum on the 20th day and minimum on the 21st day. Significant correlation between Cp activity and Cu concentration in dam serum was also revealed. In conclusion it is suggested that Zn accumulation in FL is strictly connected with MT synthesis but Cu content in FL is rather dependent on Cp activity in dam serum. Iron accumulation in fetal livers is connected with the diminution of iron concentrations in dam serum.