Kim J K, Lee C J
Korea Atomic Energy Research Institute, 150 Dukjin-dong, Yusong-gu, Taejon, South Korea.
Mutat Res. 2000 Apr 3;449(1-2):33-9. doi: 10.1016/s0027-5107(00)00027-0.
The present study was performed to obtain the evidence of the radioprotective function of melatonin on gamma-radiation-induced follicular atresia in mouse ovary. Three-week-old immature mice received 10 and 100 microg of melatonin dissolved in 100 microl of the alcoholic saline. Two hours after the treatments, they were whole-body irradiated with a dose of LD(80(30)) (8.3 Gy). The ovaries were dissected out of the animals at -2, 2, 8, 14 h after the onset of irradiation. The total number of follicles including the normal and atretic follicles examined in the largest cross sections was 125. The number was reduced to 103 in the irradiated group. The number of primordial follicles of the irradiation group or the melatonin-treated group was smaller than that of the control group. However, the number of primary, preantral, and antral follicles was not different from that of the control group. In the group pretreated with 100 microg of melatonin before irradiation, the ratio of normal primordial follicles was significantly higher than that of the irradiation group at any time point after irradiation. The high concentration of melatonin also reduced the radiation-induced degeneration of the primary follicles at 14 h after irradiation. On the other hand, the pretreatment of 10 microg of melatonin had little or no effect on the radiation-induced degeneration of primary follicles. However, it gave a protective effect on the radiation-induced degeneration in the primordial follicles at 2 h after irradiation, and 14 h after irradiation in preantral and antral follicles. From the above results, it is concluded that the exogenous melatonin has different functions depending on the follicle stages, and that the radioprotective effect of exogenous melatonin on the follicular degeneration is related to its concentration.
本研究旨在获得褪黑素对γ射线诱导的小鼠卵巢卵泡闭锁的辐射防护作用的证据。三周龄未成熟小鼠接受溶解于100微升酒精盐水中的10微克和100微克褪黑素。处理后两小时，它们接受8.3 Gy的全身照射。在照射开始后的-2、2、8、14小时从动物体内取出卵巢。在最大横切面中检查的包括正常卵泡和闭锁卵泡在内的卵泡总数为125个。照射组的卵泡数减少到103个。照射组或褪黑素处理组的原始卵泡数均少于对照组。然而，初级卵泡、窦前卵泡和窦卵泡的数量与对照组无差异。在照射前用100微克褪黑素预处理的组中，照射后任何时间点正常原始卵泡的比例均显著高于照射组。高浓度的褪黑素还减少了照射后14小时初级卵泡的辐射诱导退化。另一方面，10微克褪黑素预处理对初级卵泡的辐射诱导退化几乎没有影响。然而，它对照射后2小时原始卵泡以及照射后14小时窦前卵泡和窦卵泡的辐射诱导退化具有保护作用。从上述结果可以得出结论，外源性褪黑素根据卵泡阶段具有不同的功能，并且外源性褪黑素对卵泡退化的辐射防护作用与其浓度有关。
