[Influence of ceruloplasmin on the embryotoxic effect of silver ions].

The effect of alimentary administration of silver salts upon embryogenesis in rats has been studied. Feeding of AgCl to pregnant female rats throughout gestation did not result in any alterations in their physiological functions, although the active copper-containing ceruloplasmin (Cp) was eliminated from the blood stream. However, anomalous development of embryos, their prenatal death or total mortality of newborn rats within the first 24 hours after birth were evidenced. The copper content in the placenta and embryonic tissues decreased appreciably. The Cu,Zn-superoxide dismutase (SOD) activity was diminished in the cytoplasm of embryonic cells alongside with its drop, though less pronounced, in the tissues of the pregnant females. The embryotoxicity of AgCl was considerably reduced by repetitive injections of native Cp to pregnant rats. Such treatment caused an increase in the SOD activity in the placenta and embryonic tissues. Mortality of the newborns also went down. It is suggested that the embryotoxic effect of AgCl is due to its ability to interfere with copper metabolism, by altering the copper-transporting function of Cp.