【摘要】 背景与目的:探讨巯基乙酸(thioglycolic acid,TGA)对孕酮诱导的爪蟾卵母细胞核成熟的影响。材料与方法:用不同浓度的TGA(5、25、125μg/ml)在体外预处理爪蟾卵母细胞2 h后,再用孕酮诱导成熟,实验并设不经TGA预处理的对照组。在培养过程中观察卵母细胞的外观和核形态,以判断生发泡破裂(GVBD)情况;在培养结束时(加入孕酮后8 h),收集卵母细胞进行荧光染色,观察染色体的状态。结果:经不同浓度TGA处理后卵母细胞的GVBD50明显缩短,与对照组比较均具有统计学意义(P均<0.05),说明TGA加快卵细胞GVBD的发生;荧光染色观察GV期卵母细胞未见凝集的染色体,第一次减数分裂中期细胞可见赤道板形成,第二次减数分裂中期细胞除染色体赤道板外,还可见第一极体(PB1)。经25 mg/ml和125 mg/ml浓度的TGA处理后,排出PB1的爪蟾卵母细胞比例明显降低(P<0.05),即抑制了MI--MII转变和第一极体的释放。结论:TGA可抑制孕酮诱导的爪蟾卵母细胞体外成熟。更多还原

【Abstract】 BACKGROUND AND AIM: To investigate the effects of thioglycolic acid(TGA) on the nuclear status during progesterone-induced in vitro Xenopus oocyte maturation.MATERIALS AND METHODS: Xenopus oocytes were treated with TGA in vitro at doses of 0,5,25 and 125 μg/ml.Germinal vesicle breakdown(GVBD) was checked during culture.Oocytes collected at 8 h were stained with hoechst 33258 to evaluate the chromosome status.RESULTS: Obvious early occurrence of GVBD was found in TGA-treated Xenopus oocytes,as indicated by GVBD50(time to which 50% of the oocytes underwent GVBD) and comparison was significant(P<0.05).In immunofluorescence-stained oocytes,no condensed chromosome was seen at GV phase,but metaphase plate was formed at MI phase and metaphase plate and the first polar body(PB1)were all observed at MII phase.However,there were lower MI-MII transition rates and PB1 extrusion rates in TGA-treated groups as compared with control(P<0.05).CONCLUSION: TGA treatment could inhibit Xenopus oocyte maturation as indicated by MI-MII transition,despite GVBD was accelerated by TGA.更多还原