Torner H, Brüssow K P, Alm H, Ràtky J, Kanitz W
Department of Reproductive Biology, Research Institute for the Biology of Farm Animals, Dummerstorf, Germany.
Theriogenology. 1998 Jul 1;50(1):39-48. doi: 10.1016/s0093-691x(98)00111-3.
The aim of this investigation was to determine the relationship between the morphology of the cumulus-oocyte-complexes (COCs) and the meiotic configuration of oocytes as an LH peak mimicked by hCG. Estrus was synchronized in a total of 29 crossbred Landrace gilts by feeding Regumate for 15 d and administering 1000 IU PMSG. The LH peak was simulated by treatment with 500 IU hCG at 80 h after PMSG. Endoscopic oocyte recovery was carried out 2 h before and 10, 22 and 34 h after hCG. Only macroscopically healthy follicles with a diameter of more than 5 mm were punctured. Altogether, 410 follicles from 57 ovaries were punctured and 251 COCs were aspirated. Oocyte recovery rate increased from 48.5% (P < 0.01) of the early, not yet preovulatory follicles (2 h before hCG) to 80.8% of late preovulatory follicles (34 h after hCG). Cumulus morphology in COCs recovered 2 h before and 10 h after hCG was heterogeneous, with most (72.9 to 57.4%; P < 0.01) showing a compact or slightly expanded cumulus. Starting at about 22 h after hCG, COC morphology changed dramatically (86.7% of COCs with expanded cumulus; P < 0.01), and 34 h after hCG, 98.3% of the COCs had only an expanded cumulus. The percentage of oocytes with a mature meiotic configuration increased (11.2; 7.1; 41.4 and 70.2%, respectively, n = 238 oocytes; P < 0.01) as the interval post hCG increased (-2, 10, 22, 34 h, respectively). Meiotic configuration was related to COC morphology: compact COCs--88.9% diplotene, expanded COCs--53.8% metaphase II (M-II), and denuded oocytes--69.2% degenerated chromatin. These results indicate that there is a relationship between oocyte recovery rate, COC morphology, and meiotic configuration and preovulatory follicle maturation after the application of hCG.
本研究的目的是确定在人绒毛膜促性腺激素（hCG）模拟促黄体生成素（LH）峰的情况下，卵丘-卵母细胞复合体（COC）的形态与卵母细胞减数分裂构型之间的关系。通过饲喂烯丙孕素15天并注射1000国际单位孕马血清促性腺激素（PMSG），使总共29头杂交长白母猪的发情同步。在注射PMSG后80小时，用500国际单位hCG进行处理以模拟LH峰。在hCG处理前2小时以及hCG处理后10、22和34小时进行内窥镜下卵母细胞回收。仅穿刺直径大于5毫米的肉眼健康卵泡。总共穿刺了来自57个卵巢的410个卵泡，吸出了25个COC。卵母细胞回收率从hCG处理前（尚未排卵前）早期卵泡（hCG处理前2小时）的48.5%（P < 0.01）增加到排卵前晚期卵泡（hCG处理后34小时）的80.8%。在hCG处理前2小时和处理后10小时回收的COC中的卵丘形态是异质的，大多数（72.9%至57.4%；P < 0.01）表现为紧密或轻度扩张的卵丘。从hCG处理后约22小时开始，COC形态发生显著变化（86.7%的COC具有扩张的卵丘；P < 0.01），在hCG处理后34小时，98.3%的COC仅具有扩张的卵丘。随着hCG处理后的时间间隔增加（分别为-2、10、22、34小时），具有成熟减数分裂构型的卵母细胞百分比增加（分别为11.2%、7.1%、41.4%和70.2%，n = 238个卵母细胞；P < 0.01）。减数分裂构型与COC形态有关：紧密的COC——88.9%处于双线期，扩张的COC——53.8%处于中期II（M-II），裸卵——69.2%染色质退化。这些结果表明，在应用hCG后，卵母细胞回收率、COC形态与减数分裂构型以及排卵前卵泡成熟之间存在关系。
