氨氮胁迫对拟穴青蟹组织器官中SOD及GPX活性的影响

Effects of ammonia-N stress on the activities of superoxide dismutase and glutathione peroxidase in different tissues and organs of Scylla paramamosain

采用实验生态学的方法,探讨海水中分别添加氨氮(以氯化铵作为氨氮源)0(对照组,C0组)、10(C10组)、20(C20组)、30(C30组)、40 mg/dm3(C40组),胁迫24、48、72、96 h对拟穴青蟹(Scylla paramamosain)各组织器官中SOD、GPX活性的影响.结果表明,拟穴青蟹鳃中SOD活性,除C40组外,其余各组在胁迫24、48 h随氨氮含量升高而升高,胁迫72、96 h则随氨氮含量升高而下降(p<0.05),C40组的则随胁迫时间延长而一直呈下降趋势;各组拟穴青蟹鳃、肝胰腺和肌肉的SOD活性变化趋势相同,鳃和肌肉SOD活性最高均出现在胁迫48 h,肝胰腺SOD活性最高则在胁迫72 h.各组拟穴青蟹鳃GPX活性在胁迫24、48和72 h随氨氮含量升高而下降,胁迫96 h随氨氮含量升高而增大;各组拟穴青蟹肝胰腺和肌肉GPX活性变化与肝胰腺SOD活性变化趋势相似,胁迫48 h,C40组拟穴青蟹肝胰腺GPX活性最高.氨氮胁迫显著影响拟穴青蟹生理效应.

In an intensive culture system,accumulation of ammonia-N,the principal end product of nitrogenous metabolism,has deleterious effects on the metabolism,growth,health and reproduction of aquatic animals.The aim of the present work was to study the physiological response of Scylla paramamosain（Estampador,1949） to ambient ammonia stress.An experimental ecology method was employed to investigate the effects of ammonia-N 0（control group）,10,20,30,40 mg/dm3 stress on the activities of superoxide dismutase（SOD） and glutathione peroxidase（GPX） in the gill,hepatopancreas and muscle of Scylla paramamosain weighing 108.15±14.47 g to ammonia-N exposure for 0,24,48,72 and 96 h.The results show the SOD activity in the gill of S.paramamosain,except for the C40 group,increased with ammonia-N concentration increasing at 24 and 48 h and decreased with the ammonia-N concentration at 72 and 96 h（p0.05）;in the case of the C40 group,the ammonia-N concentration decreased throughout the 96 h of ammonia-N stress.The changes in SOD activity in the hepatopancreas and muscle of crabs in all groups had the same trend,with the gill and muscle SOD activity peaking at 48 h and the hepatopancreas SOD activity peaking at 72 h.The GPX activity was initially related inversely with the ammonia-N concentration,increasing after 24,48 and 72 h,but had a positive relation after 96 h.The GPX activity in the hepatopancreas and muscle of crabs in all groups had the same change trend as SOD activity in the hepatopancreas of crabs.Thus,ammonia-N stress appreciably affected the physiological-biochemical parameter of Scylla paramamosain.The findings will provide theoretical guidance to water quality management for mud crab aquaculture and basic data on the environmental physiology of crustaceans.