SD大鼠体外受精与早期胚胎体外培养体系的初步建立

Establishment of a Modified in vitro Rat Oocytes Fertilization and Embryo Culture System

目的 改造IVF-30和HTFplus培养液，观察在改造后培养液里卵的受精和早期胚胎的发育状况，寻找适合SD大鼠体外受精和早期胚胎培养的实验体系。方法 采用两种方法（超数排卵及体内成熟）采集成熟卵母细胞用于体外受精。选择两种商品化的培养液IVF-30（Vitrolife），HTFplus（Lifeglobal）。分别在以上的培养基中增加10、20、30mmol／L的NaCl，将培养液的渗透压提升至325～355mOsM之间，观察在改造前与改造后的培养液内SD大鼠卵母细胞受精率和囊胚发育率等指标。结果 经改造的培养液HTFplus和IVF-30，体外受精率分别从13％、15％提升至70％、67％。改造后的IVF-30和HTFplus的2细胞，大于4细胞及囊胚的发育率分别为85％，74％，22％；96％，75％，32％。HTFplus，IVF-30经过改造后更适合于SD大鼠的体外受精及早期胚胎培养。与超排相比较更多的在自然周期的体内成熟卵母细胞（16％，28％）发育到了囊胚。结论 成功建立了SD大鼠的体外受精和体外培养系统。

Objective The Sprague-Dawley rat strain is one of most popular animal models for studies of folliculogenesis, oocyte maturation and reproductive toxicology. The aim of the present study was to determine the optimal conditions for in vitro fertilization （IVF） and culture system of Sprague-Dawley rat oocytes. Methods Rat oocytes obtained from superovulation or natural ovulation cycle were fertilized and cultured in the HTF and IVF-30 media, modified by supplement with NaCl in different concentrations. Penetration of sperm, pronuclear and blastocyst formation were observed. Results Oocytes fertilized and subsequently cultured in IVF-30 or HTFplus supplemented with 30 mmol/L NaCl showed fertilization rates （67%, 70% ） with subsequent blastocyst formation rates, 22% and 32%, respectively, significantly higher than the fertilization rates （15% and 13%, respectively） with no blastocyst formation in original media. More oocytes from natural ovulation cycles （28%） developed into blastocyst than that from superovulation （ 16% ） . Conclusion An in vitro fertilization and culture system for SD rat oocytes has been successfully established.