Hatanaka F, Wada M
Department of Biology, School of Education, Waseda University, Tokyo, Japan.
Gen Comp Endocrinol. 1988 Apr;70(1):101-8. doi: 10.1016/0016-6480(88)90098-6.
A so-called "night-interruption" experiment with a 15-min light pulse showed that a sensitive phase for the photoperiodic LH secretion in male Japanese quail extended over a period of 2 hr from 12.5 to 14.5 hr after dawn. Exposure of a 1-hr light pulse at this photosensitive phase to male quail kept under 8L:16D induced the increase of plasma LH concentrations just the same as quail transferred to 16L:8D. In the first few days of photostimulation either by night interruption or by long days, LH concentrations increased at several hours after the photosensitive phase and decreased to the basal levels before day-break. The amplitude and duration of this LH surge was somewhat like a preovulatory LH surge in females. However barbiturate anesthesia (pentobarbital and phenobarbital) administered on, before, or after the photosensitive phase did not block the LH increase by photostimulation. On the other hand, an injection of phenobarbital 14 hr before the expected ovulation blocked a preovulatory LH surge, even though the same drug failed to block photoinduced LH increase in females. These results indicate that the neuroendocrine mechanism involved in photostimulated LH release is different from that for an LH surge during an ovulatory cycle.
一项使用15分钟光脉冲的所谓“夜间中断”实验表明，雄性日本鹌鹑光周期促黄体生成素（LH）分泌的敏感阶段在黎明后12.5至14.5小时持续2小时。在此光敏阶段对处于8小时光照：16小时黑暗（8L:16D）条件下的雄性鹌鹑进行1小时光脉冲照射，血浆LH浓度的增加与转移到16小时光照：8小时黑暗（16L:8D）条件下的鹌鹑相同。在通过夜间中断或长日照进行光刺激的最初几天，LH浓度在光敏阶段后的几个小时内升高，并在黎明前降至基础水平。这种LH激增的幅度和持续时间有点类似于雌性动物排卵前的LH激增。然而，在光敏阶段期间、之前或之后给予巴比妥类麻醉剂（戊巴比妥和苯巴比妥）并不能阻止光刺激引起的LH增加。另一方面，在预期排卵前14小时注射苯巴比妥可阻断排卵前的LH激增，尽管相同药物未能阻断雌性动物光诱导的LH增加。这些结果表明，光刺激LH释放所涉及的神经内分泌机制与排卵周期中LH激增的机制不同。
