Control of follicular maturation by the combination of cellular interaction and gonadotoropin

1.卵泡膜细胞和卵泡刺激素对牛促性腺激素非依赖性卵泡生长过程中颗粒细胞分化的影响我们研究了卵泡膜细胞或FSH对牛早期卵泡生长过程中颗粒细胞分化和类固醇产生的影响，使用共培养系统，其中颗粒细胞和卵泡膜细胞在胶原膜的相对两侧培养。从早期有腔卵泡（2- 4 mm）中分离卵泡细胞，这些卵泡被认为处于促性腺激素非依赖性阶段，并且就在募集到卵泡波之前。在无血清条件下培养颗粒细胞，有和没有卵泡膜细胞或重组人FSH，以测试其对颗粒细胞分化的影响。这项研究证实了卵泡膜细胞参与了雌激素产生的两个限速步骤;即，雄激素底物的产生和芳香化酶的调节，以及卵泡膜细胞衍生的因子调节雌二醇和孕酮的产生，其方式反映了发情周期卵泡期的类固醇生成。2.卵巢基质细胞的体外分化：颗粒细胞对牛卵泡膜细胞募集的影响卵泡膜细胞（TC）层的形成是卵泡生长早期最重要的生理事件之一。然而，关于TC从未分化的卵巢基质细胞募集的机制知之甚少。在本研究中，我们证实了GC参与卵巢皮质基质细胞的功能分化和LH反应性的获得。

1.Effects of ovarian theca cells and follicle-stimulating hormone on granulosa cell differentiation during gonadotropin-independent follicular growth in cattleWe investigated the effects of theca cells or FSH on granulosa cell differentiation and steroid production during bovine early follicular growth, using a co-culture system in which granulosa and theca cells were cultured on opposite sides of a collagen membrane. Follicular cells were isolated from early antral follicles (2-4mm) that were assumed to be in gonadotropin-independent phase and just before recruitment into a follicular wave. Granulosa cells were cultured under serum-free conditions with and without theca cells or recombinant human FSH to test their effects on granulosa cell differentiation. This study verified that theca cells are involved in both rate-limiting steps in estrogen production ; i.e., androgen substrate production and aromatase regulation, and that theca cell-derived factors regulate estradiol and progesterone production in a way that reflects steroidogenesis during the follicular phase of the estrous cycle.2.Differentiation of ovarian stromal cells in vitro : Effect of granulosa cellson the theca cell recruitment in cattleFormation of a theca cell (TC) layer is one of the most important physiological events during early follicular growth. However, little is known about the mechanisms of the TC recruitment from undifferentiated ovarian stromal cells. In this study we have verified that GC are involved in functional differentiation and acquisition of LH responsiveness of stromal cells from the ovarian cortex.