The permeability of the hamster placenta to radioactive cadmium

Abstract
Studies on the permeability of the mammalian placenta to teratogenic agents during the early critical stages of embryogenesis have been relatively few. Most of these studies have been done in the pregnant rabbit, in which the unusually large size of the blastocyst makes it possible to obtain samples of blastocyst fluid for analysis. Thus, investigations have been done on the permeability of the rabbit blastocyst wall to trypan blue and other teratogenic azo dyes (Ferm, 1956), changes in blastocyst sugar content following maternal administration of insulin (Curry & Ferm, 1962; Lutwak-Mann, 1962) and the effect of thalido-mide and other agents on the implanting rabbit blastocyst (Lutwak-Mann & Hay, 1962; Hay, 1964; Fabro, Smith & Williams, 1965; Keberle et al. 1965; Fabro, Hague & Smith, 1967).