镉对河南华溪蟹肝胰腺线粒体自由基代谢的影响

Effects of cadmium on hepatopancreas mitochondrial free radical metabolism in freshwater crab Sinopotamon henanense

为了探明镉对线粒体自由基代谢的毒性机理,采用急性毒性实验方法,研究了不同浓度镉(Cd2+)对河南华溪蟹(Sinopotamon henanen肝胰腺组织线粒体抗超氧阴离子(O2.-)能力、抑制羟自由基(.OH)产生能力、过氧化氢(H2O2)和一氧化氮(NO)含量及一氧化氮合成(NOS)活力的影响.具体实验设置5个Cd2+浓度组(7.25、14.50、29.00、58.00和116.00mg.L-1),分别在24、48、72和96h时对自由基代的相关指标进行测定.结果显示,Cd2+对线粒体自由基代谢的影响表现出时间和浓度效应关系.随着Cd2+浓度的增加和处理时间的延长O2.-能力、抑制.OH产生能力逐渐降低,但H2O2含量逐渐增高,NO含量和NOS活力的变化基本趋于一致,即随着Cd2+浓度的增加和处理间的延长先上升后下降.因此,线粒体中抗O2.-和抑制.OH产生能力、H2O2和NO含量及NOS活力可以作为重金属污染水生生物毒性效应指示物.

In order to study the effects of cadmium on the free radical metabolism of hepatopancreas mitochondria,freshwater crab Sinopotamon henanense was exposed to cadmium with various concentration（7.25,14.50,29.00,58.00 and 116.00 mg · L-1） for 24,48,72 and 96 h.The indices were investigated including the capabilities of anti—O·-2 and inhibit—· OH,the contents of H2O2 and NO,as well as the activity of NOS in hepatopancreas mitochondria.The results showed that the effects of cadmium on mitochondrial free radical metabolism displayed in a time-and concentration-dependent manner.With the increase of Cd2＋ concentration and duration of treatment,the capabilities of anti-O·-2 and inhibit-· OH decreased.In contrast,H2O2 content increased gradually;NO content and NOS activity changed in a same trend.They increased initially and decreased subsequently following the increase of Cd2＋ concentration and duration of treatment.Therefore,the capabilities of anti—O·-2 and inhibit—· OH,the contents of H2O2 and NO,as well as the activity of NOS in mitochondria could be considered as biomarkers of the heavy metal pollution in aquatic ecosystems.