The initiation of follicle growth: the oocyte or the somatic cells?
The initiation of follicle growth: the oocyte or the somatic cells?
复制标题
DOI：
10.1016/s0303-7207(01)00699-2
复制
发表时间：
2002-02-22
影响因子：
4.1
通讯作者：
Braw-Tal, R
中科院分区：
文献类型：
--
作者：
Braw-Tal, R
卵泡生长的起始是指原始卵泡从静止期向生长期的转变。第一阶段的特征是颗粒细胞从扁平到立方形的转变及其增殖。这与卵泡抑素表达一致。在第二阶段。颗粒细胞数量的增加伴随着卵母细胞大小的增加。来自其他物种的证据证实了这一观察结果。立方颗粒细胞的存在似乎是卵母细胞开始生长的先决条件。绝大多数牛原始卵泡在无血清培养基中培养时进入第一生长期。对人原始卵泡也得到了类似的结果。卵母细胞来源的两种蛋白质。GDF 9和BMP 15在初级阶段之后的颗粒细胞增殖中发挥重要作用。可以推测，卵泡生长起始的调节是一个两阶段的事件：第一阶段取决于局部产生的抑制和刺激因子;在第二阶段，卵泡成为自主单位。进一步的发育取决于卵母细胞产生的GDF 9 BMP 15和来自颗粒细胞的试剂盒配体。(C)2002爱思唯尔科学爱尔兰有限公司保留所有权利。
The initiation of Follicle growth is defined as the transition of primordial follicles from the quiescent to the growth phase, We have shogun that follicle growth initiation consists of two distinct, consecutive phases. The first phase is characterized by the transformation of granulosa cells from flattened to cuboidal in shape and by their proliferation. this coincides with follistatin expression. During the second phase. an increase in the number of granulosa Cells is accompanied by an increase in the size of the oocyte. Evidence from other species confirms this observation. It seems that a prerequisite for initiation of oocyte growth is the presence of cuboidal granulosa cells. The vast majority of bovine primordial follicles enter the first phase of growth when cultured in serum-free medium. Similar results ha c been obtained For human primordial follicles. Two proteins of oocyte origin. GDF9 and BMP15 play an essential role in granulosa cell proliferation beyond the primary stage. It can be speculated that the regulation of follicle growth initiation is a two-phase event: the first phase depends on locally produced inhibitory and stimulatory factor(s): in the second phase the follicle become in autonomous unit. hose further development depends on oocyte-produced GDF9 BMP15 and the kit ligand derived from granulosa cells. (C) 2002 Elsevier Science Ireland Ltd. All rights reserved.