McNeilly A S, Crow W, Brooks J, Evans G
MRC Reproductive Bioloy Unit, University of Edinburgh, UK.
J Reprod Fertil Suppl. 1992;45:5-19.
The growth of large oestrogenic follicles that have the potential to ovulate if given an appropriate luteinizing hormone (LH) signal is dictated by the plasma concentration of follicle-stimulating hormone (FSH). Basal amounts of LH are essential for this FSH-induced follicle growth, but pulses of LH do not appear to be essential. The fall in FSH concentration during the follicular phase of the oestrous cycle in sheep, and the subsequent withdrawal of FSH from other developing follicles may not be sufficient to explain follicle selection. There is little evidence to support an active suppression of the growth of other follicles by a factor(s) produced by the dominant, or selected follicle. It is possible that LH pulses cause active atresia of non-selected follicles. The selected follicle is the one that can survive the fall in plasma FSH and the large increase in LH pulses during the follicular phase and selection may simply be a case of being the follicle(s) that is present at the correct time to receive adequate FSH and develop sufficiently to survive the inhibitory effects of LH pulses. Several mechanisms whereby LH pulses may inhibit follicle growth are suggested, and avenues for future research, particularly related to the expression of the LH receptor on granulosa cells of the developing follicle, are outlined.
如果给予适当的促黄体生成素（LH）信号，具有排卵潜力的大型雌激素卵泡的生长受促卵泡激素（FSH）血浆浓度的支配。基础量的LH对于这种FSH诱导的卵泡生长至关重要，但LH脉冲似乎并非必不可少。绵羊发情周期卵泡期FSH浓度的下降，以及随后从其他发育中的卵泡中撤出FSH，可能不足以解释卵泡选择。几乎没有证据支持优势卵泡或选定卵泡产生的因子对其他卵泡生长的主动抑制。LH脉冲可能导致未选定卵泡的主动闭锁。选定的卵泡是能够在卵泡期血浆FSH下降和LH脉冲大幅增加中存活的卵泡，选择可能仅仅是在正确时间存在以接受足够FSH并充分发育以在LH脉冲抑制作用下存活的卵泡的情况。提出了LH脉冲可能抑制卵泡生长的几种机制，并概述了未来研究的途径，特别是与发育中卵泡颗粒细胞上LH受体的表达有关的途径。
