Khatir H, Lonergan P, Touzé J L, Mermillod P
Station de la Physiologie de la Reproduction, INRA, Nouzilly, France.
Theriogenology. 1998 Dec;50(8):1201-10. doi: 10.1016/s0093-691x(98)00220-9.
We have previously shown that the addition of epidermal growth factor (EGF) during in vitro maturation was capable of stimulating the cytoplasmic maturation of cow and calf oocytes. The aim of the present study was to compare calf and cow blastocysts produced in the presence of EGF in terms of total cell number and cell distribution between trophectoderm (TE) and inner cell mass (ICM), pattern of protein synthesis, and ability to establish pregnancy after embryo transfer to recipients. For all experiment, embryos at Day 7 were obtained from IVM/IVF/IVC oocytes. No significant differences were noted in total cell number (cow = 138 +/- 46 vs calf = 142 +/- 59; mean +/- SD) or ICM and TE cell number between calf (ICM = 35 +/- 19, TE = 107 +/- 52) and cow (ICM = 38 +/- 21, TE = 99 +/- 32) blastocysts, nor in the ICM/total cell number ratio (cow = 0.27 +/- 11, calf = 0.25 +/- 12). No differences were noted in the constitutive and the neosynthetic protein profiles between cow and calf embryos obtained in vitro. The results of embryo transfer, showed that there was higher pregnancy loss following transfer of calf compared with cow embryos. After Day 35, the rate of pregnancy decreases, with only 22% of calf embryos maintaining pregnancy until calving compared with 39% for cow embryos. In conclusion, it would seem that embryos originating from calf oocytes are less capable of establishing pregnancies than embryos obtained from adult oocytes, although this difference was not significant. This low viability cannot be explained by differences in cell number or by the protein profiles identified between these 2 groups of embryos.
我们之前已经表明，在体外成熟过程中添加表皮生长因子（EGF）能够刺激奶牛和犊牛卵母细胞的细胞质成熟。本研究的目的是比较在EGF存在的情况下产生的犊牛和奶牛囊胚，比较其总细胞数、滋养外胚层（TE）和内细胞团（ICM）之间的细胞分布、蛋白质合成模式以及胚胎移植到受体后建立妊娠的能力。对于所有实验，第7天的胚胎取自体外成熟/体外受精/体外培养的卵母细胞。犊牛（ICM = 35 +/- 19，TE = 107 +/- 52）和奶牛（ICM = 38 +/- 21，TE = 99 +/- 32）囊胚在总细胞数（奶牛 = 138 +/- 46 vs犊牛 = 142 +/- 59；平均值 +/- 标准差）或ICM和TE细胞数方面，以及ICM/总细胞数比值（奶牛 = 0.27 +/- 11，犊牛 = 0.25 +/- 12）方面均未观察到显著差异。在体外获得的奶牛和犊牛胚胎之间，组成型和新合成蛋白质谱也没有差异。胚胎移植的结果表明，与奶牛胚胎相比，犊牛胚胎移植后的妊娠损失更高。在第35天后，妊娠率下降，只有22%的犊牛胚胎维持妊娠直至产犊，而奶牛胚胎为39%。总之，似乎源自犊牛卵母细胞的胚胎比源自成年卵母细胞的胚胎建立妊娠的能力更弱，尽管这种差异并不显著。这种低活力无法通过这两组胚胎之间的细胞数量差异或蛋白质谱来解释。
