盐度驯化过程中虹鳟血清渗透压、激素水平及离子组成的变化  

The changes in osmotic pressure,concentrations of hormones,and ion composition in serum of rainbow trout during salinity acclimation

作　　者：班红琴[1] 吴垠[1] 李阳[1] 付鑫[1] 宋晶[1] 

机构地区：[1]大连海洋大学辽宁省水生生物学重点实验室,辽宁大连116023

出　　处：《大连水产学院学报》2010年第6期551-555,共5页Journal of Dalian Fisheries University

基　　金：辽宁省科技厅攻关项目(990368)

摘　　要：在0、8、16、24、32 5个盐度梯度下对虹鳟Oncorhynchus mykiss进行驯化,研究了盐度对虹鳟血清中3种激素含量、渗透压以及离子浓度的影响。结果表明:淡水中虹鳟的血清渗透压最低,但进入盐度为8、16的水体中时,其渗透压迅速升高,之后随着驯化时间的延长明显下降,盐度为24时其渗透压变化较小,盐度为32时其渗透压稍有下降并稳定在(327.0±2.7)mOsm/kg;随着盐度的升高,虹鳟血清中的皮质醇(COR)含量明显增加,在盐度为24时又开始下降;血清中三碘甲状腺原氨酸(T3)含量整体上随盐度的升高呈下降趋势,而四碘甲状腺原氨酸(T4)含量在盐度为16时最低,之后随盐度的升高而增加;随着盐度的提高,虹鳟血清中Na+、Cl-浓度均呈现出明显上升趋势;血清中K+浓度在盐度升至8时的第4 h出现急剧下降,之后在第96 h又有所回升,在盐度为24的第96 h上升到最高(3.76 mmol/L±0.05mmol/L),在盐度为32的第4 h又下降至最低(1.14 mmol/L±0.15 mmol/L);血清中Ca2+浓度在盐度为0～16时的变化趋势与K+相似,从盐度为24时开始显著上升,到盐度为32时的第96 h上升至最高值(3.39 mmol/L±0.01 mmol/L);除盐度为32时的Ca2+>K+之外,各盐度条件下虹鳟血清中Na+、K+、Cl-、Ca2+4种离子浓度的高低顺序均为Na+>Cl->K+>Ca2+。本研究结果表明:虹鳟在高渗环境下,能迅速启动海水中渗透压的调节机制,在皮质醇、T3、T4等几种激素共同作用下增强对高盐度的适应能力。Concentrations of three hormones,and ions and osmotic pressure were measured in serum of rainbow trout Oncorhynchus mykiss during seawater acclimation in different salinities（0,8,16,24,and 32） for 4 hours and 96 hours.The fish had the minimum serum osmotic pressure when exposed to freshwater,but significant increase just when exposed to a salinity of 8 and 16,decrease appreciably later on.There was decline in osmotic pressure in the fish exposed to a salinity of 24,and then in a same case in the fish exposed to a salinity of 32,finally stabilized at（327.0±2.7） mOsm/kg.Rainbow trout transferred from freshwater into seawater showed increase in serum cortisol levels,but decrease at a salinity of 24.Serum T3 concentration was found decrease in the rainbow trout exposed to high salinity.On the contrary,the fish exposed to a salinity of 16 had the minimum T4 content,and then had increase all the time.The Na＋ and Cl-concentrations in serum was found to be increased significantly with the ascending salinity.K＋ concentration was found to be sharply reduced in the 4th hour in salinity 8,and then rose in 96th hours in the fish exposed to the same salinity.Afterward K＋ concentration rose to the maximum value in salinity 24,followed by dropping to the minimum（1.14± 0.15） mmol/L in salinity 32.The Ca2＋ was same as K＋ in salinity from 0 to 16,but after salinity 24 exposure,Ca2＋ concentrations ascended right until the maximum values（3.39±0.01） mmol/L was observed in the 96th hours in a salinity of 32.Except that Ca2＋K＋ in salinity 32,the concentrations of four kinds of ions in rainbow trout serum in different salinities were in sequence as： Na＋Cl-K＋ Ca2＋.It can be concluded that rainbow trout can rapidly activate the adjustment mechanism of osmotic pressure to change the osmolarity in serum in the hypertonic environment,and enhance high-salinity adaptation capacity under the combined effects of several hormones（cortisol,T3,and T4）.

关 键 词：虹鳟 盐度驯化 激素 渗透压 血清离子 

分 类 号：S917[农业科学—水产科学]