Kon Hiroe, Hokao Ryoji, Shinoda Motoo
Laboratory Animal Research Center, Dokkyo Medical University, 880 Kitakobayashi, Mibu, Tochigi 321-0293, Japan.
Exp Anim. 2014;63(2):175-82. doi: 10.1538/expanim.63.175.
We investigated the fertilization and developmental ability of superovulated eggs obtained from adult Wistar-Imamichi (WI) rats, by using pregnant mare serum gonadotropin (PMSG) and human chorionic gonadotropin (hCG) treatment. Female WI rats, 11-13 weeks of age, were divided into four groups by estrous stage (metestrus [ME], diestrus [DE], proestrus [PE], or estrus [E]). PMSG (150 IU/kg) and hCG (75 IU/kg) were injected at an interval of 48 or 55 h and the female rats were mated with mature male rats. The ovulated eggs were collected 20, 24, and 27 h after hCG injection. Regardless of the estrous stage at the time of PMSG injection, the treated rats mated and ovulated similar to the untreated spontaneously ovulated rats (S group). Although the proportion of fertilized eggs in the E- and PE-treated groups was less than the S group 20 h after hCG injection, the proportion was not different among all treated and S groups 24 h after hCG injection. The proportion of fertilized eggs using in vitro fertilization and the proportion of offspring obtained from 2-cell stage embryo transfer did not differ among the treated and S groups. In comparison with PMSG/hCG-treated immature rats, mating and ovulation rate of adult rats were significantly higher. The proportion of fertilized eggs obtained from mated rats did not differ between immature and adult rats. These results demonstrate that adult WI rats are good egg donors for reproductive biotechnological studies using unfertilized or fertilized eggs.
我们通过使用孕马血清促性腺激素（PMSG）和人绒毛膜促性腺激素（hCG）处理，研究了从成年Wistar-Imamichi（WI）大鼠获得的超排卵卵的受精和发育能力。将11-13周龄的雌性WI大鼠按发情阶段（间情期[ME]、动情间期[DE]、动情前期[PE]或发情期[E]）分为四组。以48或55小时的间隔注射PMSG（150 IU/kg）和hCG（75 IU/kg），并将雌性大鼠与成熟雄性大鼠交配。在hCG注射后20、24和27小时收集排卵的卵。无论PMSG注射时的发情阶段如何，处理后的大鼠交配和排卵情况与未处理的自然排卵大鼠（S组）相似。虽然在hCG注射后20小时，E组和PE组处理后的受精卵比例低于S组，但在hCG注射后24小时，所有处理组和S组之间的比例没有差异。体外受精获得的受精卵比例以及从2细胞期胚胎移植获得的后代比例在处理组和S组之间没有差异。与PMSG/hCG处理的未成熟大鼠相比，成年大鼠的交配和排卵率显著更高。交配大鼠获得的受精卵比例在未成熟大鼠和成年大鼠之间没有差异。这些结果表明，成年WI大鼠是用于未受精卵或受精卵生殖生物技术研究的良好卵供体。
