Study on the toxicity of cadmium chloride in the postimplanted mouse embryo

Abstract

An embryotoxicity study on cadmium chloride was carried out in Swiss Albino mice. The in vitro experiments were performed to investigate the direct toxic effects of cadmium chloride on the developing embryo. Mouse’s embryo within their yolk-sacs were explanted from the uterus on gestation day 8 and cultured in the presence of cadmium chloride (0.5-3.0 µM) for 48 hours. There was significant reduction in growth accompanied by a variety of dysmorphogenic effects. Non-closure of the cranial neural tube region and stunted telencephalic hemispheres were most evident. These were observed at concentrations of cadmium chloride with no apparent adverse effects on the yolk sac circulatory system. The in vivo embryotoxic potential of cadmium chloride was evaluated in Swiss Albino mice after intraperitoneal administration of a single dose of 4 mg kg[superscript -1] on gestation day 7, 7.5 or 8.5 Significant effects of cadmium chloride were not observed on the dams. Resorption of implants was higher in the treated animals than controls when dams were treated on day 7 of gestation. Fetuses from dams given cadmium chloride were significantly smaller than those from controls. Skeletal and gross malformations were found in fetuses born to mothers which received cadmium chloride. The incidence of gross malformations were higher in treated animals than controls when dams were treated on day 7 or 7.5 of gestation. Major gross malformation were exencephaly and open eyes. The incidence of skeletal malformations were higher in treated animals than controls when dams were treated day 7.5 or 8.5 of gestation. Skeletal malformation were fused ribs, short rib, missing rib, bifurcated rib, rudimentary and flying rib, fused vertebral arches, hemivertebral arch and poorly ossified skull. Postnatal study revealed no functional impairment in fetuses born to mothers which were treated with cadmium chloride on day 8.5 of gestation. Those in effects appear to be comparable to the in vivo observations and suggest a direct teratogenic action of cadmium chloride on the developing mouse embryo.