Tropical Biosphere Research Center, University of the Ryukyus, 3422 Sesoko, Motobu, Okinawa 905-0227, Japan.
J Fish Biol. 2010 Jan;76(1):7-26. doi: 10.1111/j.1095-8649.2009.02481.x.
Reproductive activities of many fish species are, to some extent, entrained to cues from the moon. During the spawning season, synchronous spawning is repeated at intervals of c. 1 month (lunar spawning cycle) and 2 weeks (semi-lunar spawning cycle) or daily according to tidal changes (tidal spawning cycle). In species showing lunar-related spawning cycles, oocytes in the ovary develop towards and mature around a specific moon phase for lunar spawners, around spring tides for semi-lunar spawners and at daytime high tides for tidal spawners. The production of sex steroid hormones also changes in accordance with synchronous oocyte development. Since the production of the steroid hormones with lunar-related reproductive periodicity is regulated by gonadotropins, it is considered that the higher parts of the hypothalamus-pituitary-gonad axis play important roles in the perception and regulation of lunar-related periodicity. It is likely that fishes perceive cues from the moon by sensory organs; however, it is still unknown how lunar cues are transduced as an endogenous rhythm exerting lunar-related spawning rhythmicity. Recent research has revealed that melatonin fluctuated according to the brightness at night, magnetic fields and the tidal cycle. In addition, cyclic changes in hydrostatic pressure had an effect on monoamine contents in the brain. These factors may be indirectly related to the exertion of lunar-related periodicity. Molecular approaches have revealed that mRNA expressions of light-sensitive clock genes change with moonlight, suggesting that brightness at night plays a role in phase-shifting or resetting of biological clocks. Some species may have evolved biological clocks in relation to lunar cycles, although it is still not known how lunar periodicities are endogenously regulated in fishes. This review demonstrates that lunar-related periodicity is utilized and incorporated by ecological and physiological mechanisms governing the reproductive success of fishes.
许多鱼类的生殖活动在某种程度上受到来自月亮的信号的影响。在繁殖季节，同步产卵每隔大约 1 个月（月产卵周期）和 2 周（半月产卵周期）或根据潮汐变化（潮汐产卵周期）每天重复。在表现出与月亮相关的产卵周期的物种中，卵巢中的卵母细胞在特定的月亮相位下发育并成熟，对于月产卵者来说是在满月时，对于半月产卵者来说是在涨潮时，对于潮汐产卵者来说是在白天涨潮时。性类固醇激素的产生也与同步卵母细胞的发育相一致。由于与月亮相关的生殖周期性的类固醇激素的产生受促性腺激素调节，因此认为下丘脑-垂体-性腺轴的较高部分在感知和调节与月亮相关的周期性方面发挥着重要作用。鱼类可能通过感觉器官感知来自月亮的信号；然而，目前尚不清楚月亮的信号如何作为一种内在节律转化为与月亮相关的产卵节律。最近的研究表明，褪黑素根据夜间的亮度、磁场和潮汐周期而波动。此外，静水压力的周期性变化对大脑中的单胺含量有影响。这些因素可能与发挥与月亮相关的周期性间接相关。分子方法表明，光敏感时钟基因的 mRNA 表达随月光变化，表明夜间的亮度在生物钟的相位移动或重置中起作用。尽管目前尚不清楚鱼类如何内在地调节月亮周期性，但一些物种可能已经进化出与月亮周期相关的生物钟。本综述表明，与月亮相关的周期性被用于和整合到控制鱼类生殖成功的生态和生理机制中。
