催乳素和牛卵泡液对胚胎体外成熟及未成熟的牛卵母细胞的影响

对催乳素和牛卵泡液在水牛卵母细胞体外成熟中的作用进行了探讨．来自屠宰场水牛卵巢的卵母细胞和卵丘细胞复合体，在含体积分数为5％CO2的培养箱中培养24～26h，然后通过体外受精测定其受精和胚胎发育能力．实验1在成熟液中添加1．0μg/mL催乳素(PRL)，卵母细胞的囊胚发育比例(12．8％)比对照组(9．1％)高但不显著．实验2添加5％牛卵泡液(BFF)，卵母细胞卵裂的比例明显高于对照组，但囊胚形成率则几乎一样；添加1．0μg/mL PRL和5％ BFF组卵母细胞卵裂的比例为38．1％，而发育成囊胚阶段的卵母细胞的比例为14％．试验结果表明：添加适宜浓度的BFF和PRL能促进未成熟的水牛卵母细胞体外成熟后的胚胎发育能力．

The effect of prolactin and bovine follicular fluid on the in vitro maturation and subsequent development of immature buffalo (Bubalus bubalis) oocytes

Buffalo oocytes with compact cumulus cells were collected from slaughterhouse ovaries and cultured in TCM 199 supplemented with 5% estrus cow serum (ECS) + 0.1 μg/mL follicle stimulating hormone (FSH), prolactin (PRL 0, 0.1, 1.0, 10 μg/mL, Experiment 1), bovine follicular fluid (BFF) (0% BFF + 1.0 μg/mL PRL, 5% BFF, 5% BFF + 1.0 μg/mL PRL, Experiment 2), incubated at 38.5 ℃ in φ = 5% CO2 in humidified air. After 24 to 26 hours of maturation, IVF was done with swim-up separated frozen-thawed buffalo spermatozoa at 1×106 mL-1 in modified Tyrodes medium (TALP). At 24 to 26 hours post insemination, the oocytes were co-cultured with granulosa cell monolayer in droplets containing culture medium. The proportion of cleaved oocytes that developed to blastocyst stage within 9 days after commencing co-culture with granulosa cell monolayer was then evaluated. In experiment 1, the proportion of cleaved oocytes that developed to blastocyst stage was higher (12.8%) at 1.0 μg/mL PRL though not significantly different from the control (9.1%). In experiment 2, addition of 5% BFF to the maturation medium had significant increase in the cleavage rate of oocytes compared to the control (30.7% vs. 21.7%, P<0.05), but did not influence the proportion of cleaved oocytes that developed into blastocysts；addition of 5% BFF+1.0 μg/mL PRL to the maturation medium had a cleavage rate of 38.1%, with 14.0% of the cleaved oocytes developing to blastocysts (P<0.05). In conclusion, the results indicate that the addition of appropriate amounts of prolactin and bovine follicular fluid to the maturation medium will enhance the maturation of immature buffalo oocytes with their subsequent development to the blastocyst stage.