Induction of hepatic metallothionein in the rabbit fetus following maternal cadmium exposure

Abstract

Timed-pregnant rabbits were administered a single, sc injection of cadmium chloride (0, 0.125, 0.25, or 0.50 mg cadmium/kg body wt) 48 hr prior to being killed at term. Although the doses chosen were below that shown to produce significant fetal lethality, the 0.50 mg/kg dose did produce a significant reduction in fetal body weight, liver weight, kidney weight, and crown-rump length while having no effect on placental weight. Fetal hepatic metallothionein levels were significantly increased at all three doses; however, a significant increase in metallothionein zinc content was seen only at the two higher doses. Metal distribution studies indicated that the increase in fetal metallothionein and the accompanying increase in cytosolic zinc coincided with an apparent redistribution of the metal from extrahepatic sites to the liver. The whole fetal content of zinc was not significantly altered by the maternal administration of cadmium.