急性升温胁迫与恢复对葛氏鲈塘鳢抗氧化酶活性的影响

Effects of Acute Raising Temperature Stress and Recovery on Antioxidant Enzyme Activities of Amur Sleeper Perccottus glenii

将体质量(13.41±6.31)g的葛氏鲈塘鳢分为3组,饲养在80 cm×60 cm×40 cm的玻璃水族箱中。对照组水温为17℃;渐变升温组的升温速率为1℃/d;急性升温组试验鱼直接由17℃水族箱转至31℃水族箱中。两个试验组水温恒定在31℃后,测定各组葛氏鲈塘鳢的死亡率,肝脏、脑和肌肉中抗氧化酶(超氧化物歧化酶、过氧化氢酶、谷胱甘肽过氧化物酶)的活性及丙二醛的浓度,以深入了解急性升温胁迫对葛氏鲈塘鳢抗氧化能力的影响,为葛氏鲈塘鳢的人工养殖提供参考。试验结果显示,急性升温组葛氏鲈塘鳢的死亡率显著高于渐变升温组(P<0.05);肝脏和脑的抗氧化酶活性升高,6 h后脑中的超氧化物歧化酶和谷胱甘肽过氧化物酶活性显著高于渐变升温组(P<0.05),恢复至17℃过程中,超氧化物歧化酶和谷胱甘肽过氧化物酶活性显著低于对照组(P<0.05);肌肉中超氧化物歧化酶活性升高,在12 h时显著高于渐变升温组(P<0.05);1 h内肝脏中丙二醛浓度显著高于对照组(P<0.05),脑中丙二醛浓度显著高于对照组和渐变升温组(P<0.05),肌肉中丙二醛浓度显著高于渐变升温组(P<0.05),而恢复过程中脑丙二醛浓度显著高于对照组(P<0.05)。试验结果表明,长时间的高温胁迫后,肝脏和脑组织受损伤无法恢复,而肌肉比肝脏和脑组织更能适应急性升温变化。脑中谷胱甘肽过氧化物酶最先响应急性升温的氧化损伤,随后超氧化物歧化酶和过氧化氢酶的活性升高抑制谷胱甘肽过氧化物酶活性。渐变升温下葛氏鲈塘鳢的存活时间更长。

Amur sleeper Perccottus glenii with body weight of(13.41±6.31)g was divided into three groups and reared in a glass aquarium of 80 cm×60 cm×40 cm at water temperature of 17℃(control group),gradual warming at a rate of 1℃/d(gradual warming group),and in acute warming group,the test fish being transferred directly from 17℃aquarium to 31℃aquarium.In the two groups the water temperature was kept at constant 31℃and the activities of antioxidant enzymes including superoxide dismutase(SOD),catalase(CAT),and glutathione peroxidase(GPX)and malondialdehyde(MDA)content were determined in liver,brain and muscle of Amur sleeper to understand the effects of acute warming stress on the antioxidant capacity and mortality rate of Amur sleeper and to provide references with industrial aquaculture of Amur sleeper.The results showed that there were significantly higher mortality rate and activities of antioxidant enzymes in liver and brain in the Amur sleeper in the acute warming group than those in the gradual warming group(P<0.05).The activities of SOD and GPX in brain were found to be significantly higher in the Amur sleeper in the acute warming group than those in gradually warming group after 6 hours(P<0.05).The activities of SOD and GPX,however,were significantly lower than those in the control group during the recovery to 17℃(P<0.05),and the activities of SOD in muscle were significantly higher than those in gradually warming group at 12 hours(P<0.05).The content of MDA in liver was significantly higher in the Amur sleeper in the acute warming group than that in control group within 1 hour(P<0.05).The content of MDA in the brain was significantly higher than that in the control group and the gradually warming group(P<0.05),and in the muscle was significantly higher than that in the gradually warming group(P<0.05),while the content of MDA in the brain during recovery was significantly higher than that in the control group(P<0.05).The findings indicated that liver and brain injury was not recovered under long-term high temperature stress,and muscle was more adaptable to acute warming than liver and brain.GPX in the brain first responded to oxidative damage caused by acute warming,and then increases in SOD and CAT activities inhibitting GPX activity.Amur sleeper can survive longer under the condition of gradual warming than under acute warming.