亚硝酸盐急性胁迫对拟穴青蟹相关免疫指标的影响

Effects of Acute Nitrite Exposure on Immunity Indicators in Scylla paramamosain

关键词:  拟穴青蟹  亚硝酸盐胁迫  碱性磷酸酶  过氧化氢酶  丙二醛

Key words:  Scylla paramamosain  nitrite stress  alkaline phosphatase  catalase  malodiadehyde

摘要:

[目的]探讨亚硝酸盐急性胁迫对拟穴青蟹(Scylla paramamosain)机体免疫力的影响,为拟穴青蟹养殖模式调整与产业化升级提供基础资料。[方法]测定拟穴青蟹在不同浓度亚硝酸盐(0 mg/L、20 mg/L、60 mg/L、100 mg/L、140 mg/L)胁迫下其组织中碱性磷酸酶(AKP)活力、过氧化氢酶(CAT)活力、丙二醛(MDA)含量在受胁迫48 h内的动态变化。[结果]亚硝酸盐胁迫浓度达60 mg/L以上时,青蟹肝胰腺及肌肉中AKP活力变化显著,肌肉中AKP活力随时间增加呈先升高后降低趋势,各组织中CAT活力变化也呈先升高后降低趋势,表现出一定的"毒兴奋效应",肝胰腺及鳃中MDA含量则随胁迫时间与胁迫浓度变化呈递增趋势。[结论]亚硝酸盐胁迫可通过破坏组织中非特异性免疫酶类体系运转,加剧组织中脂质过氧化方式导致机体免疫力下降。在拟穴青蟹人工养殖中,将亚硝酸盐浓度控制在20 mg/L以下,有助于青蟹养殖模式调整与产业化升级。

Abstract:

[Objective] To investigate the effect of ambient nitrite on the immunity response, and to provide the basic data for the adjustment and industrialization of Scylla paramamosain, this nitrite stress experiment was designed.[Methods] In this experiment, mud crabs were divided into four nitrite exposed groups(20 mg/L, 60 mg/L, 100 mg/L and 140 mg/L ambient nitrite concentrations)and control group. Alkaline phosphatase(AKP) activity, catalase(CAT) activity and malodiadehyde(MDA) content were measured after 3 h, 6 h, 12 h, 24 h and 48 h stress.[Results] The results showed that after treated in high concentration (above 60 mg/L) nitrite exposure, AKP activity varied significantly in hepatopancreas and muscle. With the increase of time, AKP activity in muscle increased first and then decreased, which was similar with the variation tendency of CAT activity in three organizations, indicating a poison-intoxication effect. The content of MDA in hepatopancreas and gills increased with the stress time and stress concentration.[Conclusion] Therefore, nitrite stress could decrease the immunity of mud crab by damaging enzymes system related to non-specific immunity and accelerating lipid peroxidation. In the artificial breeding of mud crabs, it would contribute to breeding pattern adjustment and industrial upgrading if the concentration of nitrite was controlled below 20 mg/L.