小鼠卵母细胞体外成熟不同阶段对钙的依赖性  

INTRACELLULAR Ca^(2+) DISTRIBUTION AND ITS ROLE IN MOUSE OOCYTES MATURATION

作　　者：王晨光[1] 邓满齐[1] 孙方臻[1] 

机构地区：[1]中国科学院发育生物学研究所分子发育生物学开放实验室,北京100080

出　　处：《实验生物学报》1998年第2期147-153,共7页Acta Biologiae Experimentalis Sinica

基　　金：美国洛克菲勒基金;中国自然科学基金(No.39670376)~~

摘　　要：本研究旨在探讨小鼠卵母细胞成熟与钙和钙调素的关系。研究发现,20μmol/L W7、50μM BAPTA/AM对GVBD发生没有影响,但阻断了中期Ⅰ的卵母细胞进入中期Ⅱ。通过测定成熟不同阶段细胞内钙的分布,发现GVBD后染色体周围区域有较高水平的钙分布,并且该现象能被加BAPTA/AM而消除。GVBD发生后6h左右高钙分布现象消失。我们还测定了成熟过程中MPF活性的变化,20μmol/L W7、50μmol/L BAPTA/AM对卵母细胞成熟过程中MPF活性的升高没有影响。结果表明:小鼠卵母细胞GVBD的发生不依赖钙和钙调素;钙和钙调素对中期Ⅰ的发育是必需的,并且核周区钙分布可能起着重要作用。To determine the role of calcium and calmodulin in mouse oocyte maturation,we examined the distribution of intracellular calcium during mouse oocyte maturation by using Mira Cal Imaging System. The calcium was present homogeneously in oocytes with intact germinal vesicle (GV)and accumulated around the nuclear region after GV breakdown (GVBD). The high level of calcium disappeared 6 hours later after GVBD. In the presence of 50 μmol/L BAPTA/AM, we failed to observe this phenomena. All eggs treat- ed with 20μmol/L W7,an antagonist of calmodulin, 50 μmol/L BAPTA/AM, a calcium chela-tor, could not develop to metaphase Ⅱ (MII),although GVBD was not affected. We also detected the activity of a cytoplasmic maturation-promoting factor(MPF). W7 and BAPTA/AM had no effects on the rise of MPF activity in the course of maturation. We suggest that compartment distribution of calcium around nuclear region plays an important role in mouse oocyte maturation.

关 键 词：小鼠 卵母细胞 体外成熟 钙 依赖性 

分 类 号：Q492.5[生物学—生理学]