Lin G R, Weng C F, Wang J I, Hwang P P
Institute of Zoology, Academia Sinica, Taipei 11529, Taiwan, Republic of China.
Physiol Biochem Zool. 1999 Jul-Aug;72(4):397-404. doi: 10.1086/316682.
The yolk diameter of cortisol-treated tilapia (Oreochromis mossambicus) larvae, immersed in freshwater (FW) containing 10 mg L-1 cortisol from 48 h postfertilization to 12 d posthatching, was significantly larger than that of control larvae after 8 d of treatment, suggesting that inhibition on larval growth occurred only after a long-term treatment with cortisol. Tilapia embryos or larvae treated with 1-10 mg L-1 cortisol for 1-2 d and then transferred to 20-30 g L-1 seawater (SW) showed reduced cumulative larval mortality in SW compared with controls. Moreover, 4-5 d of cortisol treatments significantly diminished the degree of increase in larval body Na content after the transfer to SW. Significant effect of cortisol on body Na content of larvae occurred as early as 4-8 h after the transfer to SW, while no significant difference was found in the ouabain binding of yolk-sac epithelia between control and cortisol-treated larvae even 12 h after the transfer. Cortisol may be involved in the early phase of SW adaptation in developing larvae, and this mechanism may be achieved by other means than increasing the Na-K-ATPase of yolk-sac epithelia.
将受精后48小时至孵化后12天的罗非鱼（莫桑比克罗非鱼）幼鱼浸泡在含有10毫克/升皮质醇的淡水中，经皮质醇处理的幼鱼卵黄直径在处理8天后显著大于对照幼鱼，这表明只有在长期用皮质醇处理后才会对幼鱼生长产生抑制作用。用1-10毫克/升皮质醇处理1-2天，然后转移到20-30克/升海水中的罗非鱼胚胎或幼鱼，与对照组相比，在海水中幼鱼的累积死亡率降低。此外，4-5天的皮质醇处理显著降低了转移到海水后幼鱼体内钠含量的增加程度。皮质醇对幼鱼体内钠含量的显著影响早在转移到海水后4-8小时就出现了，而即使在转移12小时后，对照幼鱼和经皮质醇处理的幼鱼卵黄囊上皮的哇巴因结合也没有显著差异。皮质醇可能参与了发育中幼鱼对海水适应的早期阶段，并且这种机制可能通过增加卵黄囊上皮钠钾ATP酶以外的其他方式实现。
