Salustri A
Department of Public Health and Cell Biology, Faculty of Medicine, University of Rome Tor Vergata, Italy.
Int J Dev Biol. 2000;44(6):591-7.
In mammals, ovulation requires a tight control of extracellular matrix modifications, within both the follicle wall and the inner mass of granulosa cells surrounding the oocyte, namely the cumulus cells. During the pre-ovulatory period, mural granulosa cells promote selective degradation of perifollicular matrix, resulting in the formation of a follicle rupture site. Conversely, cumulus cells synthesize a large amount of a muco-elastic matrix that plays an essential role in the extrusion of the oocyte from the follicle and in the subsequent fertilization process. Formation of such matrix by cumulus cells in the pre-ovulatory follicle appears to be controlled by a paracrine influence by the oocyte. We have shown that mouse oocytes modulate the response of cumulus cells to an ovulatory gonadotropin stimulus by promoting the synthesis and preventing the degradation of cumulus matrix. Therefore, although gonadotropins are essential for triggering the complex events involved in ovulation, the oocyte appears to have an active role in this process. In the present review current data and hypotheses concerning molecular mechanisms involved in the organization and synthesis of cumulus matrix are discussed.
在哺乳动物中，排卵需要严格控制细胞外基质的修饰，这在卵泡壁以及围绕卵母细胞的颗粒细胞内部物质（即卵丘细胞）中都存在。在排卵前期，壁层颗粒细胞促进卵泡周围基质的选择性降解，从而形成卵泡破裂位点。相反，卵丘细胞合成大量的黏液弹性基质，该基质在卵母细胞从卵泡中排出以及随后的受精过程中起着至关重要的作用。排卵前卵泡中的卵丘细胞形成这种基质似乎受卵母细胞的旁分泌影响所控制。我们已经表明，小鼠卵母细胞通过促进卵丘基质的合成并阻止其降解来调节卵丘细胞对排卵促性腺激素刺激的反应。因此，尽管促性腺激素对于触发排卵所涉及的复杂事件至关重要，但卵母细胞在这一过程中似乎也发挥着积极作用。在本综述中，我们讨论了有关卵丘基质组织和合成所涉及分子机制的当前数据和假说。
