In Vitro Maturation and Parthenogenetic Activation of Bovine and Porcine Oocytes

卵母细胞的孤雌激活是当前哺乳动物克隆方案的关键组成部分。本研究旨在研究不同年龄牛和猪卵母细胞在不同激活刺激后的细胞变化。实验1和实验2分别用100 Vmm、50μsec的电脉冲、钙离子载体、放线菌酮或6-二甲氨基嘌呤激活体外成熟22、30和40 h的牛卵母细胞。这表明，年龄较大的牛卵母细胞更容易被激活，年龄相关的表面超微结构的变化与年龄相关的激活卵母细胞。结果还表明，牛卵母细胞的表面特征的孤雌刺激的组合发生了更深刻的变化，超微结构的影响是可逆的。在实验3和4中，猪卵母细胞体外成熟，以检查卵母细胞成熟过程中卵丘-卵母细胞结合的形态动力学 ...更多信息 成熟结果表明，在MI期和MII期之间，卵丘-卵母细胞的跨带投射由于卵丘扩张而变得不连续。然而，积云-积云通信在这些阶段保持完好。在实验5和6中，评价了电或化学激活的猪卵母细胞的激活率、发育模式以及微管和微丝组装的变化与卵母细胞老化的关系。目前的研究结果表明，在两个电脉冲后，在猪卵母细胞中获得了较高的激活率，在钙离子载体或乙醇处理后，微管的解体和微丝分布的改变，观察到在老化的卵母细胞可能会导致较高的发生率二倍体单性生殖和碎片，分别。还表明，电脉冲和CD联合处理后囊胚发育的增加可能是由于CD处理产生的二倍体单性生殖体的发生率较高。少

Parthenogenetic activation of oocytes is a key component of the current mammalian cloning regimen. This study was designed to examine the cellular alterations of the bovine and porcine oocytes at different ages following different activation stimulations. In Experiments 1 and 2, bovine oocytes of 22,30 and 40 h after in vitro maturation was activated by an electrical pulse (100Vmm, 50μsec), Ca ionophore, and combined with cycloheximide or 6-dimethylaminopurine. It is suggested that older bovine oocytes are more readily activated and that the age-dependent surface ultrastructural alterations correlate very well with the age dependent activation of oocytes. It was also shown that surface characteristics of the bovine oocyte were more profoundly changed by a combination of parthenogenetic stimulation, and that the ultrastructural effects were reversible. In Experiments 3 and 4, porcine oocytes were matured in vitro to examine morphodynamics of the cumulus-oocyte association during oocyte … More maturation. It was concluded that the cumulus-oocyte transzonal projections became disconnected between MI and MII stage as a result of cumulus expansion. However, the cumulus-cumulus communications remained intact at these stages. In Experiments 5 and 6, the activation rate, developmental pattern and changes in microtubule and microfilament assembly of the porcine oocytes activated electrically or chemically were evaluated in relation to the oocyte aging. The present results suggest that a higher activation rate was obtained in the porcine oocytes after two electrical pulses that in those after Ca ionophore or ethanol treatments and that the disorganization of microtubule and the alteration of microfilament distribution observed in the aged oocyte may result in higher incidences of diploid parthenotes and fragmentation, respectively. It is also suggested that increased development to blastocysts after the combined treatment of electrical pulses and CD may due to higher incidence of diploid parthenotes derived from CD treatment. Less