低氧胁迫对西伯利亚鲟幼鱼生理状态的影响

Effects of Hypoxia on Physiological Status of Siberian Sturgeon Acipenser baeri Juveniles

为探究低氧胁迫对西伯利亚鲟幼鱼的血液基础指标、抗氧化和能量代谢相关酶活力的影响,以体质量为(19.46±4.9)g的西伯利亚鲟幼鱼为研究对象,开展了低氧(2.3mg/L)胁迫3h和自高氧(18.5mg/L)逐渐降至低氧(2.8mg/L)又恢复到正常溶氧(7mg/L),这两种不同情况下的低氧胁迫试验。检测了血液红细胞数、血红蛋白质量浓度,以及肝脏和肌肉的抗氧化酶活力和鳃组织三磷酸腺苷酶活力。结果显示,低氧胁迫下西伯利亚鲟幼鱼血红细胞数升高,血红蛋白质量浓度、血液pH、肝脏和肌肉的超氧化物歧化酶和过氧化氢酶活力以及碱性磷酸酶活力均低于正常溶氧组,而鳃组织钠/钾—三磷酸腺苷酶活力无明显变化。试验结果显示,急性低氧胁迫能较快使西伯利亚鲟幼鱼血液红细胞数目增加,并影响肝脏、肌肉的抗氧化应激及代谢相关酶活力,但是短时间内西伯利亚鲟幼鱼可能还未实现鳃部的能量调节。

Effects of acute hypoxia stress and drastic changes in dissolved oxygen levels from 18.5mg/L to2.8mg/L then recovery to 7mg/L on blood parameters,antioxidant and metabolism were studied in Siberian sturgeon Acipenser baeri with body weight of（19.46±4.9）g.Erythrocyte count,total hemoglobin concentration,activities of antioxidant enzymes in livers and muscle,and activities of Na＋/K＋-ATPase in gills were measured in the experiment.The results showed that erythrocytic number was elevated,while hemoglobin concentration and pH of whole blood under hypoxia stress were lower than those in the control group.Hypoxia stress also depressed the activities of superoxide dismutase（SOD）,catalase（CAT）and alkaline phosphatase（AKP）in juvenile sturgeon.Nevertheless,there were no obvious changes in the activities of Na＋/K＋-ATPase in gills of Siberian sturgeon juveniles.Based on the results above,it is suggested that hypoxia stress could easily lead to the enhancement of erythrocyte amount,also reduce the activities of antioxidant and metabolism enzymes in livers or muscle of the juveniles.However,sturgeon juveniles could not achieve energy adjustment in gills itself within a short time.