Nilsson B O, Hjertén S
Biol Reprod. 1982 Sep;27(2):485-93. doi: 10.1095/biolreprod27.2.485.
An apparatus for free-zone electrophoresis was used to measure changes in the zeta potential or net negative surface charge density of mouse blastocysts. Delayed (inactive) and implanting blastocysts, recovered from the uterine cavity, were analyzed before and after incubation with neuraminidase. Growth-arrested and growth-activated blastocysts, obtained by blastocyst culture, were also examined. The results showed that the net negative surface charge density of the blastocysts decreased by 30% at implantation and at growth in culture, suggesting that the changes of the blastocyst surface at implantation are intrinsic cell membrane changes, and not caused by environmental alterations. The neuraminidase treatment decreased the net negative charge density of both delayed and implanting blastocysts by 30-60%. Thus the influence of this treatment varied too greatly among the blastocysts to permit any conclusions to be drawn about differences in the total amount of sialic acid between delayed and implanting blastocysts. Further, both delayed and implanting blastocysts carried negatively charged groups other than sialic acid containing ones. Scanning electron microscopy revealed surface changes on the blastocysts both after electrophoresis and after neuraminidase incubation; the former changes were probably normally occurring contractions, while the latter represented true alterations of the cell surface.
使用一种自由区电泳装置来测量小鼠囊胚的ζ电位或净负表面电荷密度的变化。从子宫腔中回收的延迟（不活跃）和正在着床的囊胚，在与神经氨酸酶孵育前后进行分析。还检查了通过囊胚培养获得的生长停滞和生长激活的囊胚。结果表明，囊胚的净负表面电荷密度在着床时和培养生长时降低了30%，这表明着床时囊胚表面的变化是细胞膜的内在变化，而非环境改变所致。神经氨酸酶处理使延迟和正在着床的囊胚的净负电荷密度均降低了30% - 60%。因此，这种处理对囊胚的影响差异太大，无法就延迟和正在着床的囊胚之间唾液酸总量的差异得出任何结论。此外，延迟和正在着床的囊胚都带有除含唾液酸基团以外的带负电荷的基团。扫描电子显微镜显示，电泳后和神经氨酸酶孵育后囊胚表面均有变化；前者的变化可能是正常发生的收缩，而后者代表细胞表面的真正改变。
