Urwin V E, Allen W R
J Reprod Fertil Suppl. 1982;32:371-81.
Concentrations of FSH, LH, chorionic gonadotrophin (CG) and progesterone were measured during early pregnancy in mares and donkeys carrying normal intraspecies and transferred extraspecies conceptuses. A secondary rise in progesterone concentrations occurred in normal intraspecies horse and donkey pregnancy soon after the appearance of CG but FSH concentrations continued to fluctuate and were not influenced by CG production. In donkeys carrying transferred horse conceptuses FSH concentrations fell sharply and progesterone concentrations rose steeply, coincidental with the appearance of abnormally high levels of CG. In horses carrying donkey conceptuses, on the other hand, there was a complete absence of CG production and in 7 of the 8 mares studied there was no secondary progesterone rise; FSH levels fluctuated as in the intraspecies pregnancies. Pregnancy continued to term in only 1 of 8 mares carrying a donkey conceptus despite attempts to maintain it in 4 animals by exogenous progestagen therapy. Our findings indicate that pituitary FSH, not CG, stimulates secondary follicular growth during normal equine pregnancy and the LH-like activity of CG induces ovulation of these follicles to form secondary corpora lutea.
在怀有正常种内和移植种间胚胎的母马和母驴的妊娠早期，对促卵泡素（FSH）、促黄体生成素（LH）、绒毛膜促性腺激素（CG）和孕酮的浓度进行了测量。在正常种内马和驴的妊娠中，CG出现后不久，孕酮浓度出现二次升高，但FSH浓度持续波动，不受CG产生的影响。在怀有移植马胚胎的母驴中，FSH浓度急剧下降，孕酮浓度急剧上升，同时出现异常高水平的CG。另一方面，在怀有驴胚胎的母马中，完全没有CG产生，在研究的8匹母马中有7匹没有出现孕酮的二次升高；FSH水平与种内妊娠一样波动。尽管对4只动物进行了外源性孕激素治疗以维持妊娠，但在怀有驴胚胎的8匹母马中只有1匹妊娠持续到足月。我们的研究结果表明，在正常马妊娠期间，垂体FSH而非CG刺激次级卵泡生长，CG的LH样活性诱导这些卵泡排卵以形成次级黄体。
