Mihm M, Austin E J, Good T E, Ireland J L, Knight P G, Roche J F, Ireland J J
Faculty of Veterinary Medicine, University College Dublin, Ballsbridge, Dublin 4, Ireland.
Biol Reprod. 2000 Sep;63(3):811-9. doi: 10.1095/biolreprod63.3.811.
A surgical procedure to aspirate follicular fluid concurrently from individual follicles from the same heifer was validated and used to determine if intrafollicular amounts of estradiol, progesterone, inhibins, activin-A, follistatins, and insulin-like growth factor binding proteins (IGFBP) differed for the future dominant compared with subordinate follicles during selection of the first wave dominant follicle. Heifers were subjected to surgery and aspiration of follicular fluid from the two or three largest follicles on Day 3 of the estrous cycle (approximately 1.5 days after emergence). Ultrasound was used to determine the fate of each aspirated follicle after surgery. At aspiration, diameter of the future dominant and largest subordinate follicle was similar in heifers. However, estradiol was higher, whereas IGFBP-4 was lower in the future dominant compared with the largest or next largest subordinate follicles. Also, the future dominant follicle in most cohorts had the highest estradiol and lowest IGFBP-4 compared with future subordinate follicles. We concluded that: IGFBP-4 and estradiol may have key roles in determining the physiological fate of follicles during selection of the first wave dominant follicle in heifers, and that both are reliable markers to predict which follicle in a growing cohort of 5- to 8.5-mm follicles becomes dominant.
一种从同一头小母牛的单个卵泡中同时抽吸卵泡液的外科手术方法得到验证，并用于确定在第一波优势卵泡选择过程中，与从属卵泡相比，未来优势卵泡内的雌二醇、孕酮、抑制素、激活素 -A、卵泡抑素和胰岛素样生长因子结合蛋白（IGFBP）的含量是否存在差异。在发情周期的第3天（卵泡出现后约1.5天），对小母牛进行手术，从两个或三个最大的卵泡中抽吸卵泡液。术后使用超声确定每个抽吸卵泡的命运。抽吸时，小母牛中未来优势卵泡和最大从属卵泡的直径相似。然而，与最大或次大的从属卵泡相比，未来优势卵泡中的雌二醇含量更高，而IGFBP-4含量更低。此外，与未来的从属卵泡相比，大多数队列中的未来优势卵泡具有最高的雌二醇和最低的IGFBP-4。我们得出结论：在小母牛第一波优势卵泡选择过程中，IGFBP-4和雌二醇可能在决定卵泡的生理命运方面起关键作用，并且两者都是预测5至8.5毫米生长卵泡群中哪个卵泡将成为优势卵泡的可靠标志物。
