水生生物学报2025，Vol.49Issue(8)：53-63,11.DOI:10.3724/1000-3207.2025.2024.0355
氨氮和亚硝酸盐胁迫对大口黑鲈幼鱼抗氧化酶活性及相关基因表达的影响
EFFECTS OF AMMONIA-N AND NITRITE STRESS ON ANTIOXIDANT ENZYME ACTIVITY AND RELATED GENE EXPRESSION IN JUVENILE MICROPTERUS SALMOIDES
摘要
Abstract
To investigate the effects of ammonia-N(NH3-N)and nitrite(NO2-)on the antioxidant functions in large-mouth bass(Micropterus salmoides),acute stress experiments were carried out under controlled laboratory conditions in this study.The 96-hour lethal concentration(LC50)for NH3-N was determined to be 45.057 mg/L,with a safe concentration set at 4.506 mg/L.For NO2-,the LC50 was 1365.514 mg/L,and the corresponding safe concentration was established at 136.551 mg/L.These safe concentrations were used as the maximum thresholds to evaluate the short-term exposure effects of NH3-N and NO2-on the antioxidant enzyme activities and related gene expression levels in largemouth bass.The results showed that as the concentration of NH3-N and NO2-increased,the weight gain rate of largemouth bass decreased.Additionally,under NO2-stress in isolation,malondialdehyde(MDA),glutathione(GSH),and total antioxidant capacity(T-AOC)activities decreased significantly.The relative expression levels of glutathione S-transferase(gst)and glutathione peroxidase(gpx)were significantly increased in gills,while superoxide dismutase(sod)expression was significantly upregulated in low-and high-concentration groups in gills and in the spleen of the medium-concentration group.The relative expression of catalase(cat)was significantly elevated in the spleen of the low-and high-concentration groups and in the gills of the high-concentration group.Under NH3-N stress in isolation,the activity of total SOD(T-SOD)decreased in the high-concentration group,MDA activity decreased in the low-concentration group,and T-AOC and GSH activities decreased in the medium-concentration group.Under ammonia nitrogen stress alone,the relative expression levels of gst,gpx,sod and cat were significantly increased in the gills.Under dual stress conditions involving NH3-N and NO2-,MDA and T-SOD activities increased in the high-concentra-tion group,while T-SOD,MDA,GSH,and T-AOC activities significantly decreased in the medium-concentration group.MDA activity decreased in the low-concentration group.Additionally,the expression levels of gst,gpx,sod,and cat were significantly elevated in liver tissue across all groups,as well as in the gills of the medium-and high-concen-tration groups.Consequently,acute stress caused by NH3-N and NO2-induces oxidative stress in largemouth bass,and changes in antioxidant enzymes and antioxidant-related genes may play a role in scavenging reactive oxygen species,thereby mitigating potential damage caused by environmental fluctuations.关键词
氨氮/亚硝酸盐/抗氧化/大口黑鲈Key words
Ammonia-N/Nitrite/Antioxidant/Micropterus salmoides分类
农业科技引用本文复制引用
杨艳杰,陈静,黄雷,彭先启,焦锦彪,牛晨,易少奎,姚嘉赟..氨氮和亚硝酸盐胁迫对大口黑鲈幼鱼抗氧化酶活性及相关基因表达的影响[J].水生生物学报,2025,49(8):53-63,11.基金项目
湖州市公益性应用研究项目(2022GZ28) （2022GZ28）
浙江省"尖兵""领雁"研发攻关计划(2024C02005)资助[Supported by the Key Project Program of Huzhou City(2022GZ28) （2024C02005）
the Zhejiang Key Research and Development Project(2024C02005)] （2024C02005）
