急性盐度胁迫对军曹鱼稚鱼渗透压调节的影响

急性盐度胁迫对军曹鱼稚鱼渗透压调节的影响

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徐力文　刘广锋　王瑞旋　苏友禄　郭志勋　冯　娟

33

(中国水产科学研究院南海水产研究所,广州510300)

摘　要　研究了环境盐度急性胁迫对军曹鱼(R achycentron canadum )稚鱼鳃Na +2K +

ATPase

(NK A )活性及血清渗透压、Na +、K +和Cl -离子调节的影响.结果表明:将稚鱼从盐度37中直

接转移至盐度0、5、15、25、37(对照)和45的水体中,12h 后仅盐度0处理出现死亡(死亡率100%).各处理鳃NK A 活性和血清渗透压在最初3h 内出现一定波动,随后变化平稳.试验结束时(12h ),NK A 活性与盐度梯度呈“U ”型分布,盐度5处理酶活性显著高于其它处理(P <

0105),盐度15处理活性最低,而各处理的血清渗透压大小(293～399mO s mol ・kg -1

)与盐度

呈正相关;在3～12h 内稚鱼血清Na +和Cl -浓度随盐度升高而升高,但增幅较小,血清K +

浓

度则与盐度呈负相关;12h 稚鱼的等渗点为32812mO s m ・kg -1,相当于盐度11148,而Na +

、K +和Cl -等离子点分别为15512、6116和13711mmol ・L -1,分别相当于盐度10168、20144及8141.军曹鱼在生理上具有广盐性鱼类的“低渗环境高NK A 活性”特征,有较强及迅速的渗透压和离子调节与平衡能力.

关键词　盐度　胁迫　军曹鱼　Na +

2K +

ATP 酶　离子和渗透压调节文章编号　1001-9332(2007)07-1596-05　中图分类号　S962　文献标识码　A Effects of abrupt s a li n ity stress on os m oregul a ti on of juven ile R achycen tron canadum .XU L i 2wen,L I U Guang 2feng,WANG Rui 2xuan,S U You 2lu,G UO Zhi 2xun,FENG Juan (South China S ea F isheries R esearch Institute,Chinese A cade m y of F ishery S ciences,Guangzhou 510300,Chi 2na ).2Ch in .J.A ppl .Ecol .,2007,18(7):1596-1600.

Abstract:R achycentron canadum is a thriving mariculture s pecies f or offshore cage in s outhern Ma 2inland and Tai w an of China,due t o its rap id gr owth rate and high quality flesh .I n this paper,the

gill Na +2K +

ATPase (NK A )activity and i ono 2and os moregulati on of juvenile R.canadum were in 2vestigated in a 12h stress of a mbient salinities (0-45),and the results showed that after an abrup t transfer t o the salinities of 0,5,15,25,37(contr ol )and 45,the death of juvenile R.canadum only occurred in salinity 0,with a mortality of 100%by the end of the experi m ent .I n all treat 2ments,the gill NK A activity and seru m os molality fluctuated in first 3h,and then changed s mooth 2ly .The NK A activity varied with salinity grade in U shape,being significantly (P <0105)higher in salinity 5and the l owest in salinity 15in 12h,while the seru m os molality (ranged 293-399

mO s mol ・kg -1)p resented a positive correlati on with salinity .Serum [Na +]and [Cl -]concen 2

trati on slightly increased with salinity within the peri od of 3-12h,while serum [K +

]dis p layed a

reverse pattern .The is os motic point was esti m ated as 32812mO s m ・kg -1

and corres ponded t o sa 2

linity 11148.The is oi onic points f or serum [Na +],[K +]and [Cl -]were esti m ated as 15512,

6116,and 13711mmol ・L -1

,which corres ponded t o the salinities of 10168,20144and 8141,re 2s pectively .It was concluded that R.canadum could be characterized physi ol ogically as a “higher 2NK A 2in 2hypos motic media ”marine euryhaline teleost with the capability of rap id and effective hy 2per/hypo i ono 2and os moregulati on .

Key words:salinity;stress;R achycen tron canadum ;Na +

2K +

ATPase;i ono 2and os moregulati on .

3广东省科技计划项目(2003B21502;2005A30502001)和广东省重大科技招标资助项目(2004A20401001).

33通讯作者.E 2mail:juanf@21cn .com 2006206205收稿,2007204205接受.

应用生态学报　2007年7月　第18卷　第7期

Chinese Journal of App lied Ecol ogy,Jul .2007,18(7):1596-1600