Department of Genetics and Marine Biotechnology, Institute of Oceanology of Polish Academy of Sciences, 81-172 Sopot, Poland.
J Fish Biol. 2009 Jul;75(1):142-55. doi: 10.1111/j.1095-8649.2009.02272.x.
In this study, melatonin (MEL) and thyroxine (T(4)) concentrations were measured during larval and postlarval development of gilthead sea bream Sparus auratus Hormones were measured in whole bodies of larvae or the head and trunk of postlarvae after 67 days of exposure to constant light, 24L:0D, constant darkness, 0L:24D or 12L:12D and in the plasma of 6 month juveniles kept under the 12L:12D, 0L:24D and 24L:0D regimes. High MEL concentrations in larvae suggested a distinct role of MEL in early organogenesis and development of S. auratus. In larvae, the gastro-intestinal tract seemed to be an important extrapineal and extraretinal source of MEL. No endogenous rhythm of MEL synthesis was demonstrated in 67 day larvae; however, in 6 month juveniles, it was evident. At early ontogenesis of S. auratus, the role of MEL is probably related mostly to the control of development and protection against free radicals, whereas its action as a time-keeping molecule develops later. The increase in T(4) concentration during the S. auratus larva-juvenile transition, i.e. between 50 and 70 days post-hatch, which was observed concurrently with the decrease of MEL concentration, may suggest an inverse relationship between T(4) and MEL.
在本研究中，褪黑素（MEL）和甲状腺素（T（4））的浓度在金头鲷 Sparus auratus 的幼虫和幼鱼发育过程中进行了测量。在持续光照（24L：0D）、持续黑暗（0L：24D）或 12L：12D 条件下暴露 67 天后，测量了幼虫整体或幼鱼头部和躯干中的激素，以及在 12L：12D、0L：24D 和 24L：0D 条件下饲养的 6 月龄幼鱼的血浆中的激素。幼虫中高浓度的 MEL 表明 MEL 在金头鲷早期器官发生和发育中具有重要作用。在幼虫中，胃肠道似乎是 MEL 的一个重要的非松果腺和非视网膜来源。在 67 天大的幼虫中没有证明 MEL 合成的内源性节律；然而，在 6 月龄幼鱼中则很明显。在金头鲷早期发育过程中，MEL 的作用可能主要与发育的控制和自由基的保护有关，而其作为计时分子的作用则后来发展。在金头鲷幼鱼-幼鱼过渡期间（即孵化后 50 至 70 天），T（4）浓度增加，同时 MEL 浓度降低，这可能表明 T（4）和 MEL 之间存在反比关系。
