低氧胁迫对珍珠龙胆石斑鱼氧化应激及能量代谢的影响

Effects of Hypoxic Stress on Antioxidant and Energy Metabolism of Hybrid Grouper(Epinephelus fuscoguttatus♀×Epinephelus lanceolatus♂)

【目的】探究保活运输中低氧胁迫对珍珠龙胆石斑鱼(Epinephelus fuscoguttatus♀×Epinephelus lanceolatus♂)氧化应激的影响。【方法】诱导体质量为(498.2±27.3)g的杂交石斑鱼进入休眠状态,并放置在溶解氧为(1.74±0.21)mg·L^(−1)的低氧环境下,低氧胁迫0、6、12、24、48、72 h后,取样测定血清应激指标,肌肉、肝脏、鳃组织氧化应激指标及肌肉、肝脏能量利用指标。【结果】低氧胁迫过程中,杂交石斑鱼血糖含量在胁迫6 h时最大,72 h时恢复胁迫前水平;皮质醇含量在胁迫过程均显著高于胁迫前;肌肉超氧化物歧化酶(SOD)活性随胁迫时间的增加而上升,肝脏、鳃SOD活性先上升后下降;肌肉、肝脏过氧化氢酶(CAT)活性呈先升后降的趋势,鳃CAT活性在胁迫12、72 h显著低于胁迫前;肌肉、肝脏丙二醛(MDA)含量在胁迫过程中均增加,鳃MDA含量先降后升;肌肉谷胱甘肽还原酶(GSH)含量在胁迫12 h达到最大值,肝脏GSH含量呈先上升后下降的趋势,鳃中GSH含量在12 h时显著高于胁迫前,之后逐渐升高;总抗氧化能力(T-AOC)在肌肉、肝脏、鳃中均呈上升的趋势;肌肉和肝脏中糖原的含量显著减少,肌肉乳酸脱氢酶(LDH)活性显著增加,肝脏LDH先降后升。显著性水平均为0.05。【结论】低氧胁迫会刺激珍珠龙胆石斑鱼产生应激反应,影响体内正常的氧化应激系统,并对不同组织造成不同程度的氧化损伤。

【Objective】To explore the effects of hypoxia stress on oxidative stress of hybrid grouper(Epinephelus fuscoguttatus♀×Epinephelus lanceolatus♂)during actual survival transportation.【Methods】Hybrid groupers[(498.2±27.3)g]were induced to enter a dormancy state and placed in hypoxic environment with the dissolved oxygen content of(1.74±0.21)mg·L^(−1).After 0,6,12,24,48 and 72 h of hypoxic stress,serum stress index,oxidative stress index of muscle,liver and gill and energy utilization index of the muscle and liver were measured.【Result】Under hypoxia stress,the serum blood glucose content reached the maximum at 6 h and recovered to the pre-stressed level at 72 h.The cortisol level during stress was significantly higher than that of the before stress.Superoxide dismutase(SOD)activity in the muscle increased with stress time,while SOD activity in the liver and gill increased initially and then decreased.Catalase(CAT)activity in the muscle and liver increased firstly and then decreased,and CAT activity in gill was significantly lower than before stress for 12 and 72 h.Malondialdehyde(MDA)content increased in muscle and liver,but decreased first and then increased in the gill.The content of glutathione reductase(GSH)in muscle reached the maximum value at 12 h,the content of GSH in liver increased firstly and then decreased,and the content of GSH in gills was significantly higher than before stress at 72 h.The total antioxidant capacity(T-AOC)increased in the muscle,liver and gill.Glycogen content in the muscle and liver was significantly reduced and lactate dehydrogenase activity significantly increased.The significance levels used in all tests were P<0.05.【Conclusion】The results showed that hypoxic stress can stimulate the stress response of hybrid grouper(E.fuscoguttatus♀×E.lanceolatus♂),affect the normal oxidative stress system in vivo,and cause different degrees of oxidative damage to different tissues.