十二烷基硫酸钠(SDS)对克氏原螯虾抗氧化功能和酸性磷酸酶活性的影响

Effects of Sodium Dodecyl Sulfate on Antioxidation Function and Acid Phosphatase Activity of Procambarus clarkii

研究了不同浓度(0、35、70、140和280 mg·L-1)十二烷基硫酸钠(SDS)对克氏原螯虾(Procambarus clarkii)肝胰腺和鳃的毒性效应。结果表明,肝胰腺和鳃超氧化物歧化酶(SOD)活性与SDS浓度及暴露时间密切相关,总体表现为低浓度(≤70 mg·L-1)下受诱导而高浓度(≥140 mg·L-1)下受抑制、暴露时间延长则活性下降的趋势,肝胰腺SOD对高浓度SDS(≥140 mg·L-1)胁迫比鳃SOD更为敏感。2种组织过氧化氢酶(CAT)活性变化趋势总体相似,表现为先升高后下降,鳃CAT活性受诱导或受抑制程度均低于肝胰腺。肝胰腺和鳃酸性磷酸酶(ACP)活性变化大体分别表现为上升—下降和下降—上升—下降,肝胰腺ACP对SDS胁迫高度敏感,暴露24 h时即出现显著受诱导现象(P<0.05或P<0.01),对SDS胁迫具有指示作用。肝胰腺和鳃还原型谷胱甘肽(GSH)含量均表现出先升高后下降趋势,两者分别在48和24 h时达最大值,肝胰腺GSH主要在抵御较低浓度SDS(≤140 mg·L-1)胁迫中发挥重要作用,而鳃GSH含量在24 h内极显著升高(P<0.01),鳃GSH比肝胰腺更容易受诱导。由此可见,克氏原螯虾可通过调节抗氧化系统及物质代谢来抵御SDS胁迫,且多数酶表现出明显的时间-剂量效应,而肝胰腺ACP和鳃GSH对SDS胁迫敏感,可作为SDS污染的潜在生物指示物。

Toxic effects of SDS on hepatopancreas and gill of freshwater crayfish, Procambarus clarkii, relative to concentration （0, 35, 70, 140 and 280 mg·L-1） were studied. Results show that SOD activities in the hepatopancreas and gill were closely related to concentration of and duration of the exposure to SDS. On the whole, SOD activity was induced by SDS low in concentration （≤70 mg·L-1）, and inhibited by SDS high in concentration （≥140 mg·L-1）, and tended to decline when exposure to SDS continued. SOD in hepatopancreas was more sensitive to high concentrations of SDS （≥140 mg·L-1） than those in gill. CAT activities in the two organs were generally similar in variation trend, that is, rising first and declining later on,but degree of the variation was lower in gill than in hepatopancreas. Acid phosphatase （ACP） activity increased and then decreased in hepatopancreas, while it went down-up-down in gill. ACP in hepatopancreas was highly sensitive to SDS and induced in activity significantly after 24h of exposure. So ACP can be used as indicator of SDS stress. Reduced glutathione （GSH） in hepatopancreas and gill displayed a similar variation trend in content, that is, rising first and declining later on. Its content peaked at 48h and 24h in hepatopancreas and gill, respectively. GSH in hepatopancreas plays an important role in resisting SDS stress relatively low in concentration （≤140 mg·L-1）, while GSH in gill increased significantly within 24h of exposure （P〈0.01）, demonstrating that GSH in gill is more likely to be induced than that in hepatopancreas. It is quite obvious that crayfish can resist SDS stress by regulating its antioxidation system and metabolism, that most enmzymes in crayfish display apparent time/dose-dependent response, and that ACP in hepatopancreas and GSH in gill is very sensitive to SDS stress, and hence can be used as the potential bioindicator of SDS pollution in water.