鳗弧菌感染对脊尾白虾鳃组织抗氧化酶系统的影响

Antioxidant Enzyme System in Gills of Shrimp Exopalaemon carinicauda Challenged with Vibrio anguillarum

为研究鳗弧菌感染对脊尾白虾鳃组织抗氧化酶系统的影响,分别对脊尾白虾注射生理盐水和鳗弧菌,注射后分别于0、3、6、12、24、48、72h测定了鳃中总抗氧化能力活性和谷胱甘肽过氧化物酶、过氧化氢酶、超氧化物歧化酶、过氧化物还原酶、谷胱甘肽S-转移酶基因表达量的变化。试验结果显示,与对照组相比,感染鳗弧菌后,鳃中总抗氧化能力活性于6h达到最大值,48h显著低于对照组（P〈0.05）;谷胱甘肽过氧化物酶基因表达量于12h达到最大值（P〈0.05）,48h逐渐降低至对照组水平;过氧化氢酶基因表达量在感染初期无显著变化,12h开始显著上升,并于24h达到最大值（P〈0.05）;超氧化物歧化酶和过氧化物还原酶基因表达变化基本一致,均于3h显著上升至最大值（P〈0.05）,6~72h始终保持较低水平;谷胱甘肽S-转移酶基因表达量从3h开始上升,并于6h达到最大值。研究表明,鳗弧菌感染对脊尾白虾鳃组织抗氧化酶系统影响显著,有明显的破坏作用;本研究所用免疫指标均可作为弧菌病诱发的监测指标。

The total antioxidant capacity and the mRNA expression levels of glutathione peroxide reductase, catalase, superoxide dismutase, peroxiredoxin and glutathione S-transferase genes were investigated in gills of healthy shrimp Exopalaernon carinicauda with body weight of （1. 18 ±0.35） g injected with sterile 0.86% saline solution and bacteriumVibrio anguillarum 0, 3, 6, 12, 24, 48, and 72 h after injec- tion to study the effect of V. anguillarum challenge on the antioxidant enzyme defense system of the shrimp. The results showed that the total antioxidant capacity in gills were found to be increased significantly in the shrimp challenged with V. anguillarum, to the peak value 6 h after administration, and then decreased gradually to a lower level than in the shrimp in the control in 48 h challenge compared with the shrimp in the control group （P〈0.05）. The expression level of glutathione peroxidase gene in the gills of the shrimp challenged with V. anguillarum was up-regulated significantly to the peak 12 h after chal- lenged （P〈0.05）, then recovered to the level in the shrimp in the control group at 48 h. There was no significant changes in the expression level of catalase gene at first 6 h, then up-regulated at 12 h, with the maximal level at 24 h （P〈0.05）. The same change tendency of superoxide dismutase and peroxide reduc- tase gene expression were observed in the shrimp challenged with V. anguillarum, increased to the peak at 3 h, then kept a stable low level from 6 h to 72 h. The expression of glutathione S-transferase gene was increased significantly to the peak level at 6 h, and then decreased to the control group level gradually at 24 and 48 h. The findings indicated that V. anguillarum challenge had noticeable impact on antioxidant enzyme defense system in gills of the shrimp and the activities of antioxidant enzymes, and the parameters measured in the present study were regarded as a monitor indicator for Vibrio diseases.