Reproductive Cycling in Fundulus Heteroclitus

小行星9306123 雌性底栖蟹在其自然栖息地排卵和产卵，一年中长达8个月的时间与春潮一致，它们也在一年中的任何时间在恒定的受控实验室条件下以半月周期产卵。 循环中雌二醇-17 β（E2）水平的高度升高与每次产卵事件有关。 一个生物钟的生殖活动，并涉及周期性的E2释放的卵巢，因此似乎存在于这个丰富的和实验方便的硬骨鱼。 为了了解影响F.对于异口产卵，Wallace博士将在几次产卵期间监测生殖活动的各个方面。 这些包括血液中的卵黄蛋白原和促性腺激素水平以及下丘脑中的生物胺水平。 如果发现卵黄蛋白原和促性腺激素水平波动，将分别在肝脏和垂体中测量相应的mRNA水平。 促性腺激素调节未成熟卵泡芳香化酶活性的方式（E2水平升高的来源）也将与卵泡在周期中不同时间对相关激素的反应能力一起讨论。 E2对周期性产卵的影响将通过在产卵周期的不同时间施用E2进行实验研究。 还将提供其他药物，以探索下丘脑-垂体-性腺轴中的因果关系。 最后，将对卵孵化模式和运动活动进行一系列观察。 如果能令人信服地证明，这种过程中的半月形图案将表明F。 heteroclitus有一个基因决定的生物钟，调节其整体生理。 ***

9306123 Wallace Fundulus heteroclitus females ovulate and spawn in their natural habitat with a semilunar periodicity coincident with spring tides for up to eight months of the year; they also spawn with a semilunar periodicity under constant, controlled laboratory conditions at any time during the year. Highly elevated levels of circulating estradiol-17 Beta (E2)are associated with each spawning episode. A biological clock for reproductive activity, and involving cyclic E2-release by the ovary, thus appears to exist in this abundant and experimentally convenient teleost. In order to appreciate the operant factors in the reproductive cycling of F. heteroclitus, various aspects of reproductive activity will be monitored by Dr. Wallace over several spawning episodes. These include vitellogenin and gonadotropin levels in the bloodstream and biogenic amine levels in the hypothalamus. If vitellogenin and gonadotropin levels are found to fluctuate, corresponding mRNA levels will be measured in the liver and pituitary, respectively. The manner by which gonadotropins regulate aromatase activity in prematurational follicles (the source of elevated E2 levels) will also be addressed together with the competence of follicles to respond to relevant hormones at various times during the cycle. The effect of E2 on cyclic spawning will be experimentally investigated by administering E2 at various times during the spawning cycle. Other drugs will also be provided in order to explore cause and effect relationships in the hypothalamic- pituitary-gonadal axis. Finally, a series of observations will be made on egg hatching patterns and locomotor activity. Semilunar patterns in such processes, if convincingly demonstrated, would indicate that F. heteroclitus has a genetically determined, biological clock that regulates its overall physiology. ***