Jenkins A S, Anderson G B
Department of Animal Science, University of California, Davis 95616.
Lab Anim Sci. 1990 Jul;40(4):371-4.
Two genetic lines of mice (Mus musculus), one selected for high embryo survival (Line E) and the other for small litter size (Line CN-), were used as models to study preimplantation embryo survival. The two lines displayed similar ovulation rates, but significantly lower embryo survival to implantation was observed in Line CN- females (P less than 0.01). The effect of the uterine environment on embryo survival was examined by incubating embryos in pseudopregnant host females for 26 hours beginning at 1500 hours on day 2 (day of copulatory plug = day 0). Embryos were then removed from the host and transferred to recipient uteri of the same genetic line as the embryos for development to term. Survival of embryos was significantly greater after exposure to Line E hosts (P less than 0.01). Survival of Line E embryos was reduced from 71% in Line E hosts to 28% in Line CN- hosts. Survival of Line CN- embryos increased from 17% in Line CN- hosts to 70% in Line E hosts. Embryos also were cultured in vitro in uterine flushings collected from each line. More Line E embryos developed to the blastocyst stage than did Line CN- embryos (P less than 0.01). Development of Line CN- (P less than 0.01) embryos, but not Line E embryos, was affected by the line from which uterine flushings were collected. These lines of mice provide a useful model for the study of the physiological basis for differences in embryo survival due to genetic selection.
选用两种品系的小鼠（小家鼠）作为研究植入前胚胎存活率的模型，一种是经选育胚胎存活率高的品系（E系），另一种是窝仔数少的品系（CN-系）。这两个品系的排卵率相似，但CN-系雌性小鼠胚胎存活至着床的比例显著更低（P<0.01）。通过将胚胎在假孕宿主雌性小鼠体内于第2天15:00开始孵育26小时，来检测子宫环境对胚胎存活的影响。然后将胚胎从宿主中取出，转移至与胚胎同基因品系的受体子宫中发育至足月。暴露于E系宿主后胚胎存活率显著更高（P<0.01）。E系胚胎在E系宿主中的存活率从71%降至CN-系宿主中的28%。CN-系胚胎在CN-系宿主中的存活率从17%增至E系宿主中的70%。胚胎也在从每个品系收集的子宫冲洗液中进行体外培养。发育至囊胚阶段的E系胚胎比CN-系胚胎更多（P<0.01）。CN-系胚胎（P<0.01）而非E系胚胎的发育受到收集子宫冲洗液的品系的影响。这些品系的小鼠为研究因基因选择导致胚胎存活差异的生理基础提供了有用的模型。
