瘦素对小鼠着床前胚胎发育影响的体外研究

目的　探讨瘦素在体外对小鼠着床前胚胎发育的影响。方法　 1收集小鼠 2 -细胞胚胎 ,在不同剂量瘦素的 CZB培养液中进行体外培养 ,观察胚胎发育情况 ,并进行胚胎移植 ,观察着床率 ;2收集小鼠 2 -细胞胚胎在空白 CZB培养液中体外培养至桑葚胚期 ,再分别置入不同剂量瘦素的 CZB培养液中进行体外培养 ,观察胚胎进一步发育情况。结果　瘦素能提高 2 -细胞胚胎体外发育的质量、发育率和胚胎着床率。当瘦素剂量为 10 ng/ ml时平均胚胎形态学评分 (AES)为 16 .0 8± 0 .37,剂量为 5 0 ng/ ml时 AES为 17.5 7± 0 .4 2 ,两者间差别有统计学意义(P<0 .0 5 )。但剂量进一步增加 ,促进作用不再递增。瘦素对桑葚胚体外进一步发育无显著影响。结论　瘦素参与了小鼠着床前胚胎的发育 ,能提高胚胎发育质量、发育率 ,有利于胚胎的进一步着床。

Effects of Leptin on Development of Mouse Preimplantation Embryos in vitro

OBJECTIVE: To investigate the effects of leptin on development of mouse preimplantation embryos in vitro. METHODS: (1) Groups of 2-cell stage embryos randomly selected were placed in drops of CZB medium with or without recombinant leptin (10, 50, 100 and 500 ng/ml) and were cultured to the hatched blastocyst stage, and then embryo-transfer was carried out and the implantation rate was observed and determined. (2) Groups of 2-cell stage embryos randomly selected were placed in drops of leptin free CZB medium and cultured to morula stage. Then we changed the medium, randomized the embryos into CZB medium with or without recombinant leptin (10, 50, 100 and 500 ng/ml), and cultured them to the hatched blastocyst stage. RESULTS: Addition of leptin to embryo culture media promoted the development from 2-cell stage embryo to morula, blastocyst and hatched blastocyst and improved the implantation rate. Leptin at 0, 10, 50 ng/ml concentrations caused a dose-dependent promotion, nevertheless Leptin at even higher concentrations (100 and 500 ng/ml) only brought on the same promotion as what the Leptin at concentration of 50 ng/ml did (P>0.05). Addition of leptin to embryo culture media seemed to have no effects on the in vitro development from morula to blastocyst and hatched blastocyst. CONCLUSION: Leptin plays an important role in the development of preimplantation embryo. It can promote embryo development and embryo implantation.