溶解氧水平对青海湖裸鲤体肾组织结构及抗氧化酶活性的影响

DISSOLVED OXYGEN LEVEL ON THE BODY KIDNEY STRUCTURE AND ANTIOXIDANT ENZYME ACTIVITIES OF QINGHAI LAKE SCALELESS CARP,GYMNOCYPRIS PRZEWALSKII

为研究溶解氧水平对青海湖裸鲤(Gymnocypris przewalskii)体肾组织结构及抗氧化酶活性的影响,选择平均体重为(97.68±0.12)g的青海湖裸鲤,随机分为三组:中度低氧组(3.0±0.1)mg/L、重度低氧组(0.7±0.1)mg/L和常氧组(8.4±0.1)mg/L,于低氧胁迫8h和24h,观察体肾显微结构和线粒体超微结构并检测线粒体膜电位及抗氧化酶活性。结果显示,中度和重度低氧胁迫对体肾显微结构和线粒体超微结构未造成损伤,但中度和重度低氧胁迫24h时体肾杆状线粒体比例增加(P<0.05),且中度和重度低氧胁迫使体肾线粒体膜电位降低(P<0.05)。中度低氧胁迫对体肾超氧化物歧化酶(SOD)活性和过氧化氢(H_(2)O_(2))含量无影响(P>0.05),但重度低氧胁迫使SOD活性和H_(2)O_(2)含量增加(P<0.05)。中度和重度低氧胁迫使体肾总抗氧化能力(T-AOC)、谷胱甘肽过氧化物酶(GPX)和丙二醛(MDA)含量增加(P<0.05)。推测为适应不同低氧环境,青海湖裸鲤体肾在线粒体形态和相关抗氧化酶活性方面做出适应性调整。研究结果为揭示青海湖裸鲤低氧适应机制提供了一定的理论依据。

To investigate the effect of dissolved oxygen(DO)on the tissue structure and activities of the antioxidant enzyme in the body kidney of the Qinghai Lake scaleless carp,Gymnocypris przewalskii,with an average weight of(97.68±0.12)g,were randomly divided into three groups with moderate hypoxia(3.0±0.1)mg/L),severe hypoxia(0.7±0.1)mg/L,and normal oxygen level(8.4±0.1)mg/L for 8h and 24h.The structure of the body kidney and the ultrastructure of the body kidney mitochondria were observed,and the membrane potential of mitochondria and the activities of antioxidant enzymes were assayed.The results showed that moderate and severe hypoxia did not damage the structure of the body kidney and ultrastructure of the mitochondria.However,moderate and severe hypoxia significantly increased the ratio of renal rod mitochondria at 24h with markedly decreased membrane potential of the mitochondria.Severe hypoxia but not moderate hypoxia significantly increased the activity of SOD and the concentration of H_(2)O_(2).Furthermore,both severe and moderate hypoxia markedly increased the concentrations of total antioxidant capacity(T-AOC),glutathione peroxidase(GPX),and malondialdehyde(MDA)in the body kidney of the scaleless carp.These results indicate that the body kidney of the scaleless carp adapt to environments via regulating mitochondrial morphology and antioxidant enzymes.This study provides a theoretical basis for understanding the hypoxia adaptation mechanism of Qinghai Lake scaleless carp.