Chian Ri-Cheng, Chung Jin-Tae, Downey Bruce R, Tan Seang Lin
Department of Obstetrics and Gynecology, McGill University, Montreal, Quebec, Canada H3A 1A1.
Reprod Biomed Online. 2002 Mar-Apr;4(2):127-32. doi: 10.1016/s1472-6483(10)61929-3.
Immature oocytes recovered from bovine ovaries were studied to determine if their maturational and developmental competence is affected by phase of folliculogenesis. Ovaries (a total of 39 pairs) were collected from a local abattoir. Following examination, each pair of ovaries was assigned to one of three groups, according to follicle size and with or without a corpus luteum: (i) early phase (n = 13 pairs): all follicles were <or=8 mm in diameter; (ii) late phase (n = 13 pairs): the largest follicle was >or=15 mm in diameter; (iii) luteal phase (n = 13 pairs): all follicles were <or=8 mm in diameter and there was a corpus luteum on one of the ovaries. All follicles were aspirated and cumulus-oocytes complexes (COC) were cultured in 1.0 ml maturation medium, TC-199 medium supplemented with 10% fetal bovine serum (FBS), 0.2 mmol pyruvate, and 75 mIU/ml FSH and LH (Humegon) at 38.5 degrees C in a humidified atmosphere of 5% CO(2) and 95% air for 24 h. Following maturation in vitro, the oocytes were inseminated with frozen-thawed semen and cultured for further development in vitro. The mean number of oocytes retrieved from early phase ovaries was 32 +/- 8.1 which was significantly higher (P < 0.05) than other phases (n = 20.1 +/- 5.4 and 22.7 +/- 6.9). The numbers of degenerated oocytes from early, late and luteal phase ovaries were not different (n = 1.6 +/- 0.7, 1.8 +/- 0.5 and 1.5 +/- 0.5, respectively). The rates of oocyte maturation (84.4%, 89.2% and 83.6%) and fertilization (53.5%, 53.3% and 51.3%) were not significantly different across the three groups. In addition, there were no significant differences in the rates of cleavage (77.9%, 79.9% and 73.9%) and blastocyst formation (27.4%, 33.0% and 30.4%) in the three groups. These results indicate that the maturational and developmental competence of immature oocytes is not affected by the phase of folliculogenesis.
研究从牛卵巢中回收的未成熟卵母细胞，以确定其成熟和发育能力是否受卵泡发生阶段的影响。从当地屠宰场收集了总共39对卵巢。检查后，根据卵泡大小以及有无黄体，将每对卵巢分配到三组中的一组：（i）早期（n = 13对）：所有卵泡直径≤8mm；（ii）晚期（n = 13对）：最大卵泡直径≥15mm；（iii）黄体期（n = 13对）：所有卵泡直径≤8mm，且其中一个卵巢上有黄体。抽吸所有卵泡，将卵丘-卵母细胞复合体（COC）在1.0ml成熟培养基（添加10%胎牛血清（FBS）、0.2mmol丙酮酸盐以及75mIU/ml促卵泡素和促黄体素（贺美奇）的TC-199培养基）中，于38.5℃、5%二氧化碳和95%空气的湿润环境中培养24小时。体外成熟后，用冻融精液使卵母细胞受精，并进一步进行体外培养。从早期卵巢回收的卵母细胞平均数量为32±8.1，显著高于其他阶段（n = 20.1±5.4和22.7±6.9）（P<0.05）。早期、晚期和黄体期卵巢中退化卵母细胞的数量无差异（分别为n = 1.6±0.7、1.8±0.5和1.5±0.5）。三组间卵母细胞成熟率（84.4%、89.2%和83.6%）和受精率（53.5%、53.3%和51.3%）无显著差异。此外，三组间的分裂率（77.9%、79.9%和73.9%）和囊胚形成率（27.4%、33.0%和30.4%）也无显著差异。这些结果表明，未成熟卵母细胞的成熟和发育能力不受卵泡发生阶段的影响。
