Nakano A, Ono M, Ohta Y, Wakisaka I
Nihon Eiseigaku Zasshi. 1989 Jun;44(2):579-86. doi: 10.1265/jjh.44.579.
To clarify the maternal-fetal transfer of cadmium across the placenta, cadmium was determined in 21 paired samples of maternal blood, placenta and umbilical cord blood obtained at delivery from pregnant women who did not smoke and had no particular exposure to cadmium compounds in their history. Cadmium was detected in all the samples. In both maternal blood and umbilical cord blood, the cadmium concentrations in the red blood cells were remarkably higher than those in the plasma. The cadmium concentration in the umbilical cord blood was significantly lower than that in the maternal blood, suggesting that the placenta might effectively block the transfer of cadmium to fetuses in pregnant women. The placental cadmium concentration was the highest in the samples determined. The ratios of placental to maternal blood cadmium concentration were very large, indicating that cadmium preferentially accumulates in the placental tissues. On the other hand, the ratios of umbilical cord blood to placental cadmium concentration were very small, indicating that the placenta constitutes an effective barrier against cadmium; that is, the placental cadmium is hard to transfer to fetuses in pregnant women. The significantly positive correlations between maternal blood and placenta, between placenta and umbilical cord blood and between maternal blood and umbilical cord blood in terms of the concentrations of cadmium suggest that the amount of cadmium accumulated in placenta and transferred from mother to fetus is strongly influenced by the cadmium body burden of the mother.
为阐明镉在胎盘处的母婴转运情况，对21对产妇分娩时采集的母血、胎盘和脐带血样本进行了镉含量测定。这些孕妇不吸烟，既往无特殊镉化合物接触史。所有样本均检测到镉。在母血和脐带血中，红细胞中的镉浓度均显著高于血浆中的镉浓度。脐带血中的镉浓度显著低于母血中的镉浓度，这表明胎盘可能有效阻止了镉向孕妇胎儿的转运。在所测定的样本中，胎盘镉浓度最高。胎盘与母血镉浓度之比非常大，表明镉优先在胎盘组织中蓄积。另一方面，脐带血与胎盘镉浓度之比非常小，表明胎盘对镉构成有效屏障；也就是说，胎盘镉很难转运至孕妇胎儿体内。镉浓度方面，母血与胎盘之间、胎盘与脐带血之间以及母血与脐带血之间存在显著正相关，这表明胎盘蓄积的镉量以及从母亲向胎儿转运的镉量受母亲镉体内负荷的强烈影响。
