小鼠孤雌胚的体内体外发育研究

STUDY ON THE DEVELOPMENT OF MOUSE PARTHENOGENETIC EMBRYOS IN VIVO AND IN VITRO

小鼠孤雌激活卵体外培养于ＣＺＢ溶液中可发育至孵出囊胚阶段，而且孤雌胚移植后可在受体子宫内附植发育。单倍体、二倍体孤雌胚发育至桑椹胚的能力相似，但发育至囊胚的能力，后者高于前者。孤雌囊胚体外发育至孵出的比率仅为２０％，但在卵巢切除的受体子宫内其发育至孵出囊胚的比率提高到７３３％。与受精扩张囊胚相比，孤雌扩张囊胚在成纤维细胞饲养层上很难贴壁生长，但延迟孤雌囊胚的内细胞团（ＩＣＭ）可在细胞饲养层上增殖，并可形成孤雌ＥＳ细胞集落。昆明鼠孤雌囊胚内细胞团细胞注射入Ｃ５７ＢＬ／６Ｊ受精囊胚腔制作的嵌合胚可完成附植后的发育，但这些后裔未见毛色嵌合。

Artificially activated oocytes (haploid or diploid) cultured in CZB medium could develop to expanded blastocyst stage,some even hatched from the zona pellucida.Very few parthenogenetic embryos could induce pregnancy after transferred into the pseudopregnant recipients in the Kunming mouse.The development capacity to morula in different type of parthenogenetic embryos (haploid or diploid) was similar but the rate of morula developing to blastocyst in diploid group was higher than that in haploid group.20% of parthenogenetic blastocysts developed to hatched blastocyst stage cultured in vitro, and it resulted in 73 3% development to hatched blastocyst stage by cultured parthenogenetic blastocysts in ovariectomized recipient.To compare with fertilized expanding blastocysts,parthenogenetic expanding blastocyst was difficult to attach to the culture surface of feeder layers from primary embryonic fibroblasts.But the inner cell mass (ICM) of delayed parthenogenetic blastocysts were easy to proliferate on culture surface,and could form parthenogenetic embryo derived stem cell colonies.Mosaic blastocysts were produced by injection one or two foreign cells into the blastocoelic cavity of mouse blastocysts.The donor cells came from ICM of parthenogenetic blastocysts of the Kunming mouse.The recipient blastocysts,aged approximately 3 5 day,were obtained by mating C57BL/6J×C57BL/6J black mice.Seven offspring were born from sixty one manipulated blastocysts,but all of them were black and no chimeras was found.