Division of Reproductive Biotechnology and Innovation, Center for Animal Resources and Development (CARD), Institute of Resource Development and Analysis, Kumamoto University, Kumamoto 860-0811, Japan.
Division of Reproductive Engineering, Center for Animal Resources and Development (CARD), Institute of Resource Development and Analysis, Kumamoto University, Kumamoto 860-0811, Japan.
J Reprod Dev. 2024 Apr 4;70(2):123-130. doi: 10.1262/jrd.2023-067. Epub 2024 Feb 26.
Genetically modified rats are valuable models in human disease research. We recently developed an improved system for rat sperm cryopreservation and in vitro fertilization (IVF) that facilitates the efficient production and preservation of genetically modified rats. In the IVF procedure performed using frozen-thawed rat sperm, the IVF schedule is fixed to ensure timely hormone administration and oocyte collection. To enhance the flexibility of the IVF schedule, possible periods of postovulated rat oocytes with normal fertility and developmental abilities should be determined. Therefore, in this study, we examined the fertilization and developmental ability of incubated oocytes 1-13 h after oocyte collection at 9:00 AM. The fertilization rate decreased 7 h after oocyte collection, and abnormally fertilized oocytes appeared 10 h after oocyte collection. The developmental rate also decreased 7 h after oocyte collection; however, live pups were obtained from oocytes 12 h after oocyte collection. In summary, ovulated rat oocytes exhibited a high developmental ability after IVF for up to 4 h after oocyte collection.
转基因大鼠是人类疾病研究中的有价值模型。我们最近开发了一种改进的大鼠精子冷冻保存和体外受精（IVF）系统，可促进转基因大鼠的高效生产和保存。在使用冷冻解冻大鼠精子进行的 IVF 程序中，IVF 方案是固定的，以确保及时进行激素给药和卵母细胞采集。为了提高 IVF 方案的灵活性，应确定排卵后大鼠卵母细胞具有正常生育力和发育能力的可能时期。因此，在这项研究中，我们检查了在上午 9 点采集卵母细胞后 1-13 小时孵育卵母细胞的受精和发育能力。受精率在卵母细胞采集后 7 小时下降，并且在卵母细胞采集后 10 小时出现异常受精的卵母细胞。卵母细胞采集后 7 小时，胚胎发育率也下降；然而，从卵母细胞采集后 12 小时的卵母细胞中获得了活产仔。总之，排卵后的大鼠卵母细胞在 IVF 后 4 小时内仍具有很高的发育能力。
