Möstl E, Janowski T, Palme R, Rás A, Zduńczyk S, Bamberg E
Zentralbl Veterinarmed A. 1989 Feb;36(2):104-9. doi: 10.1111/j.1439-0442.1989.tb00709.x.
From Day 268 of gestation till two days after parturition blood samples were collected from the jugular vein of 5 cows with normal and 4 cows with flumethasone induced parturition and centrifuged immediately after sampling. In another experiment blood samples were taken from the jugular and uterine vein of 3 cows during the last week before normal parturition. The dehydroepiandrosterone (DHA) and epitestosterone (ET) concentrations in plasma were measured using radioimmunoassay. In the control group the DHA concentration was in the range of 2 to 5 nmol/l, ET levels varied from 4 to 8 nmol/l before term. In both groups, there was an increase in DHA concentrations during the last periparturient period whereas ET levels increased only after flumethasone induced parturition. The concentrations of both androgens declined after the expulsion of the placenta and they were higher in the uterine vein than in the jugular vein. It is concluded, that both androgens are secreted by the bovine placenta and that the delta 5-pathway of steroidogenesis is active in vivo.
从妊娠第268天至分娩后两天，从5头正常分娩的母牛和4头用氟米松诱导分娩的母牛的颈静脉采集血样，并在采样后立即离心。在另一项实验中，在正常分娩前的最后一周，从3头母牛的颈静脉和子宫静脉采集血样。使用放射免疫分析法测定血浆中的脱氢表雄酮（DHA）和表睾酮（ET）浓度。对照组中，足月前DHA浓度在2至5 nmol/l范围内，ET水平在4至8 nmol/l之间变化。在两组中，围产期最后阶段DHA浓度均升高，而ET水平仅在氟米松诱导分娩后升高。胎盘排出后，两种雄激素的浓度均下降，且子宫静脉中的浓度高于颈静脉。得出的结论是，两种雄激素均由牛胎盘分泌，且类固醇生成的δ5途径在体内具有活性。
