绵羊卵泡成分对卵母细胞体外减数分裂调控的研究  

THE EFFECTS OF FOLLICULAR COMPONENTS ON MEIOSIS PROGRESSION OF OVINE OOCYTES CULTURED IN VITRO

作　　者：布赫[1] 旭日干[1] 

机构地区：[1]内蒙古大学哺乳动物生殖生物学教育部重点实验室,呼和浩特100021

出　　处：《细胞生物学杂志》2003年第2期116-120,共5页Chinese Journal of Cell Biology

基　　金：国家自然科学基金资助;项目编号 39860056

摘　　要：哺乳动物卵巢中的卵母细胞一直处于减数分裂的停滞状态,卵泡内各成分被认为是产生抑制因子的主要来源。本研究以绵羊卵泡各成分为研究对象,用共培养的方法对卵丘细胞、颗粒细胞、膜细胞在卵母细胞体外减数分裂过程中的作用加以探讨。结果表明:1.卵泡整体及卵泡分泌物在体外可以有效地维持减数分裂停滞,经过24h培养,这两个处理组中,处于GV期的卵母细胞分别为69.6％和49.1％。经抑制处理后的卵母细胞脱离抑制环境后可以继发成熟,MⅡ比率可达88.9％。去掉卵丘细胞的裸卵其减数分裂过程不能被卵泡分泌物有效抑制,24h培养后其GV期比例为17.8％。以上结果说明卵泡中的抑制因子主要是通过卵丘细胞来发挥其调控作用的。2.用颗粒细胞与卵母细胞共培养,结果发现具有颗粒细胞卵丘细胞缝隙连接的卵母细胞(COCs)在培养24小时后47.4％达到MⅡ,与在不具有细胞连接的悬浮颗粒细胞中共培养的卵母细胞之间存在无显著差异,无论是紧密连接的颗粒细胞层还是悬浮在培养液中的颗粒细胞都不能有效抑制生发泡破裂(GVBD)的发生,只能将卵母细胞抑制在MⅡ以前的各个时期。以上结果说明颗粒细胞在体外分泌抑制因子的活力大大下降。3.卵泡膜细胞具有分泌抑制成熟分裂因子的能力,与膜细胞层共培养的卵母细胞在8h和24h时。Mammalian oocytes are arrested at dictyate stage of the first meiotic division in the ovary. The present studies were undertaken to evaluate the inhibitory effect of follicular components that including granulosa cells, cumulus cells and theca cells in vitro. 1. Injected in the whole intact follicle or cultured in the se-retion of follicles,oocytes could be maintained in meiosis arrest in high proportion. In the two groups, the percentages of oocytes arrested in GV stage were 69.6% and 49.1% , respectively. When the oocytes were removed from the follicles and put into the maturation medium,88.9% of them reached MⅡ stage.The meiosis resumption of denuded oocytes can not be prevented by secretion of follicles, only with 17. 8% of oocytes arrested in GV stage. The results showed that the meiosis arrest was controlled by inhibitory factors through the gap junction. 2. When cumulus oocyte complexes (COCs)with granulosa cells were cultured in vitro for 24h, 47.4% reached Mil stage. Neither granulosa cells that had intact gap junctions with COCs nor granulosa cells in co-culture could prevent the GVBD of COCs. The result showed that the secretion of inhibitory factors in granulosa cells declined significantly in vitro. 3. Theca cells can secrete inhibitory factors to maintain oocytes in meiosis arrest. When oocytes were co-cultured with theca cells for 8h and 24h, the percentages of oocytes in GV stage were 34. 4% and 32.7% , respectively, significantly higher than in theca cell-free medium(4.5% and 1.1%). In conclusion, the inhibitory factors in ovine follicle not only come from granulosa cells but also theca cells. These cells still to some extent have the ability to secret inhibitory factors in vitro. The inhibitory factors or signals transmit mainly through gap junction between cumulus cells and oocyte.

关 键 词：绵羊 卵泡成分 卵母细胞 减数分裂 调控 卵丘细胞束 颗粒细胞 抑制因子 膜细胞 体外共培养 

分 类 号：Q343[生物学—遗传学]