Flint A P, Burrow P V
J Endocrinol. 1979 Aug;82(2):287-91. doi: 10.1677/joe.0.0820287.
Epitestosterone, a product of the metabolism of androstenedione by the caprine placenta in vitro, is present in the plasma of the pregnant goat. The maternal concentrations of both epitestosterone and unconjugated oestrogens (mostly oestradiol-17 alpha) in the blood increased before parturition and dropped post partum. Measurement of arteriovenous differences at term indicated that epitestosterone was secreted by the uterus; its production was not dependent on the presence of corpora lutea. It is suggested that the concentration of epitestosterone (+ androstenedione + oestrogens) in maternal plasma may be used as an indicator of placental C-17,20 lyase activity; the slight rise in the concentration of these compounds prepartum suggests a relatively small increase in flow through this enzyme.
表睾酮是雄烯二酮经山羊胎盘体外代谢的产物，存在于怀孕母羊的血浆中。分娩前母羊血液中表睾酮和未结合雌激素（主要是雌二醇-17α）的浓度升高，产后下降。足月时动静脉差异的测量表明，表睾酮由子宫分泌；其产生不依赖于黄体的存在。有人提出，母羊血浆中表睾酮（+雄烯二酮+雌激素）的浓度可用作胎盘C-17,20裂解酶活性的指标；这些化合物在产前浓度的轻微升高表明通过该酶的流量相对小幅增加。
