Vreeburg J T, Woutersen P J, Ooms M P, van der Werff ten Bosch J J
J Endocrinol. 1981 Jan;88(1):9-16. doi: 10.1677/joe.0.0880009.
Testosterone was measured in plasma pools from male and female fetal guinea-pigs between the ages of 30 and 55 days of pregnancy. Between days 33 and 36 the testosterone concentration in the plasma of males (1.4 ng/ml) was several times higher than that found at other ages or that measured in female fetuses. After infusion of tritiated testosterone for 2 h into pregnant guinea-pigs at day 36 of pregnancy, high levels of testosterone and androstenedione were found in maternal plasma. Nevertheless, tritiated testosterone and androstenedione could hardly be shown in the fetuses. Similar large differences in plasma progesterone levels appeared to exist between the maternal and the fetal circulation. Therefore, only a very small fraction of these steroids can penetrate from the maternal circulation into that of the fetus. This finding might be explained by the large difference in androgen-binding capacity between maternal and fetal plasma, as was shown by equilibrium dialysis.
对妊娠30至55天的雄性和雌性豚鼠胎儿的血浆池进行了睾酮测定。在妊娠第33至36天之间，雄性胎儿血浆中的睾酮浓度（1.4纳克/毫升）比其他年龄段或雌性胎儿血浆中的睾酮浓度高出数倍。在妊娠第36天给怀孕的豚鼠注入氚标记的睾酮2小时后，母体血浆中发现了高水平的睾酮和雄烯二酮。然而，在胎儿体内几乎检测不到氚标记的睾酮和雄烯二酮。母体和胎儿循环中的血浆孕酮水平似乎也存在类似的巨大差异。因此，这些类固醇中只有极小一部分能够从母体循环进入胎儿循环。正如平衡透析所显示的，这一发现可能是由于母体和胎儿血浆中雄激素结合能力的巨大差异所致。
