Dumoulin J C, Evers J L, Michiels A H, Pieters M H, Bras M, Land J A, Geraedts J P
Department of Obstetrics/Gynaecology, Academic Hospital Maastricht, University of Limburg, The Netherlands.
Mol Reprod Dev. 1993 Nov;36(3):320-7. doi: 10.1002/mrd.1080360306.
The effect of various potassium concentrations (ranging from 1.4 mM to 30 mM K+) in modified Tyrode's medium on the culture of mouse zygotes obtained after in vitro fertilization to the blastocyst stage was examined. A clear dose-dependent negative effect of increasing K+ concentrations on the preimplantation embryonic development in vitro was found. We have previously shown that significantly more two-cell embryos reach the blastocyst stage when cultured during the second day postinsemination in medium supplemented with taurine. Because taurine, an amino acid that abounds in the reproductive tract, has been reported to inhibit the enzyme Na(+)-K(+)-adenosine triphosphatase (Na(+)-K(+)-ATPase), we used two other conditions known to inhibit the Na(+)-K(+)-ATPase to study their effect on mouse embryo development. Culturing embryos during a short period (the second day postinsemination) in low extracellular K+ concentrations (1.4 mM) or in medium supplemented with ouabain (50 microM) showed positive effects similar to those of culturing in medium with taurine (10 mM). This beneficial effect of ouabain was found in various K+ concentrations tested, including the high concentrations present in the oviduct. Although the effects of low K+ and taurine can possibly be ascribed to their other cellular effects, the effect of ouabain shows that inhibition of the Na(+)-K(+)-ATPase during the two-cell stage in the mouse is beneficial for further embryonic development to the blastocyst stage.
研究了改良台氏液中不同钾离子浓度（1.4 mM至30 mM K+）对体外受精后获得的小鼠受精卵培养至囊胚阶段的影响。发现钾离子浓度升高对体外着床前胚胎发育有明显的剂量依赖性负面影响。我们之前已经表明，在补充牛磺酸的培养基中授精后第二天培养时，显著更多的二细胞胚胎能够发育至囊胚阶段。由于据报道，生殖道中丰富的氨基酸牛磺酸可抑制钠钾-腺苷三磷酸酶（Na(+)-K(+)-ATPase），我们使用另外两种已知可抑制钠钾-腺苷三磷酸酶的条件来研究它们对小鼠胚胎发育的影响。在低细胞外钾离子浓度（1.4 mM）下或在补充哇巴因（50 microM）的培养基中短时间（授精后第二天）培养胚胎，显示出与在含有牛磺酸（10 mM）的培养基中培养相似的积极效果。在包括输卵管中存在的高浓度在内的各种测试钾离子浓度下，均发现了哇巴因的这种有益作用。虽然低钾离子和牛磺酸的作用可能归因于它们的其他细胞效应，但哇巴因的作用表明，在小鼠二细胞阶段抑制钠钾-腺苷三磷酸酶有利于胚胎进一步发育至囊胚阶段。
