Funahashi H, Stumpf T T, Cantley T C, Kim N H, Day B N
Department of Animal Sciences, University of Missouri-Columbia, USA.
Zygote. 1995 Aug;3(3):273-81. doi: 10.1017/s0967199400002677.
Pronuclear formation and intracellular content of glutathione, containing reduced and oxidised forms, in porcine oocytes matured in vitro were determined following insemination and/or electrical stimulation. After insemination, sperm penetration had occurred as early as 3 h and female pronuclei had formed by 6 h with complete development by 12 h. Male pronuclear formation occurred, primarily, between 9 and 12 h after insemination. Glutathione content of the oocytes decreased following sperm penetration and remained at a depressed level until 12 h. After electrical stimulation, oocyte activation had occurred and female pronuclei had formed by 3 and 6 h, respectively. Oocyte glutathione content did not change as a result of oocyte activation. When oocytes were exposed to an electrical pulse and then spermatozoa, female pronuclear formation was observed by 3 h after stimulation/insemination. Sperm penetration was observed between 3 and 9 h. However, the incidence of male pronuclear formation observed at 12 h was extremely low, although sperm decondensation had occurred in some oocytes. Oocyte glutathione content had not decreased by 6 h following electrical activation. These results demonstrate that the changes in glutathione content in porcine oocytes following fertilisation in vitro differ from those due to electrical activation. Further, the decreased intracellular glutathione content in oocytes activated by sperm penetration appears to be due to the presence of a sperm factor.
在体外成熟的猪卵母细胞中，授精和/或电刺激后，测定了原核形成以及谷胱甘肽（包括还原型和氧化型）的细胞内含量。授精后，精子最早在3小时穿透，6小时形成雌原核，12小时完全发育。雄原核形成主要发生在授精后9至12小时之间。精子穿透后，卵母细胞的谷胱甘肽含量下降，并在12小时前一直维持在较低水平。电刺激后，卵母细胞分别在3小时和6小时发生激活并形成雌原核。卵母细胞激活后，其谷胱甘肽含量未发生变化。当卵母细胞先接受电脉冲然后再接触精子时，刺激/授精后3小时观察到雌原核形成。精子穿透发生在3至9小时之间。然而，尽管在一些卵母细胞中精子已解聚，但12小时时观察到的雄原核形成发生率极低。电激活后6小时，卵母细胞的谷胱甘肽含量并未下降。这些结果表明，体外受精后猪卵母细胞中谷胱甘肽含量的变化与电激活引起的变化不同。此外，精子穿透激活的卵母细胞中细胞内谷胱甘肽含量的下降似乎是由于精子因子的存在。
