Wallace E M, Crossley J A, Groome N P, Aitken D A
Department of Obstetrics and Gynaecology, University of Edinburgh, UK.
J Endocrinol. 1997 Jan;152(1):109-12. doi: 10.1677/joe.0.1520109.
Recently, inhibin-A has been shown to be a useful new prenatal marker of Down's syndrome, significantly increasing detection rates. While the placenta is believed to be the major source of inhibin in pregnancy, there are actually very limited data available on specific inhibin dimers in pregnancy. Using a sensitive and specific ELISA we have measured the inhibin-A content of amniotic fluid (AF) to investigate further the biology of inhibin-A in chromosomally normal and abnormal pregnancies. AF from 51 Down's syndrome and 161 chromosomally normal pregnancies between 16 and 19 weeks of gestation were analysed, blinded as to whether the sample was from a Down's syndrome or normal pregnancy. There were no sex differences in inhibin-A content in either the control or Down's syndrome pregnancies. The median (10-90th percentiles) inhibin-A level in the control pregnancies increased from 339.6 (175.2-649.1) pg/ml at 16 weeks to 592.9 (256.4-1027.3) pg/ml at 19 weeks of gestation. The median (95% confidence interval) inhibin-A in the Down's syndrome pregnancies, expressed as multiples of the median (MoM) to correct for gestation, was 0.77 (0.68-0.89) MoM, significantly lower than the controls (P < 0.001, Mann-Whitney U test). We believe that these data are compatible with more than one source of inhibin-A in pregnancy and suggest that the fetal membranes may be contributing significantly to AF inhibin-A content. Further, our data would suggest that the endocrine function of the placenta and the other inhibin source(s) are differentially regulated.
最近，抑制素A已被证明是一种有用的唐氏综合征产前新标志物，可显著提高检测率。虽然胎盘被认为是孕期抑制素的主要来源，但实际上关于孕期特定抑制素二聚体的数据非常有限。我们使用一种灵敏且特异的酶联免疫吸附测定法（ELISA）测量了羊水（AF）中的抑制素A含量，以进一步研究抑制素A在染色体正常和异常妊娠中的生物学特性。对妊娠16至19周的51例唐氏综合征妊娠和161例染色体正常妊娠的羊水进行了分析，分析时不知道样本来自唐氏综合征妊娠还是正常妊娠。在对照妊娠和唐氏综合征妊娠中，抑制素A含量均无性别差异。对照妊娠中抑制素A水平的中位数（第10 - 90百分位数）从妊娠16周时的339.6（175.2 - 649.1）pg/ml增加到妊娠19周时的592.9（256.4 - 1027.3）pg/ml。唐氏综合征妊娠中抑制素A的中位数（95%置信区间），以中位数倍数（MoM）表示以校正孕周，为0.77（0.68 - 0.89）MoM，显著低于对照组（P < 0.001，曼-惠特尼U检验）。我们认为这些数据与孕期抑制素A的多种来源相符，并表明胎膜可能对羊水抑制素A含量有显著贡献。此外，我们的数据表明胎盘和其他抑制素来源的内分泌功能受到不同的调节。
