镉对瓯江彩鲤脏器组织蛋白质的氧化损伤作用

Oxidative Damage of Cadmium to Protein in the Viscera Tissues of Cyprinus carpio var color

瓯江彩鲤(Cyprinus carpio var color)是浙江省大力推广的主要稻田养鱼鱼种,重金属污染对其生态毒理效应研究具有重要意义。针对镉胁迫瓯江彩鲤蛋白质氧化损伤效应,采用静态置换法,研究了0.412～2.059mg·L-1浓度范围内的镉对瓯江彩鲤鳃、脑和肝脏组织蛋白质的氧化损伤作用。结果表明,瓯江彩鲤鳃、脑和肝组织蛋白质羰基(PCO)含量随着镉暴露浓度的增加而升高,且均表现出明显的浓度-效应关系,线性拟和确定系数分别为0.9660,0.9630和0.9723;在0.686～2.059mg·L-1浓度组,各脏器组织PCO含量均明显高于对照组(p<0.05或p<0.01)。在胁迫剂量为0.686mg·L-1不同暴露时间条件下,鳃、脑和肝组织蛋白质羰基含量随暴露时间的延长而升高,3种组织中PCO含量在暴露7d后均显著高于对照组(p<0.05)。3种组织蛋白质羰基含量变化对镉暴露敏感性大小的次序为:肝>鳃>脑。结果显示,镉可引起细胞蛋白质产生氧化损伤,镉对不同组织器官的蛋白质氧化损伤程度不同;PCO可以做为评价重金属污染对鱼体生态毒效应的有效生物标志物。

Cyprinus carpio vat color are the major species bred in rice paddy in Zhejiang Province. The study concerning ecotoxicological effects of heavy metal contamination on Cyprinus carpio vat color was significant. In this paper, accord- ing to the effect of protein oxidative damage induced by cadmium stress, static displacement method was conducted to explore the degree of protein oxidative damage in gill, brian and liver of Cyprinus carpio var color by cadmium. The fishes were exposed to 0.412, 0.515, 0.686, 1.029, 2.059 mg＇L 1 cadI＇Niu, nl, respectively for 7 days under experimental condi- tions. The results showed that protein carbonyl （PCO） content in gill, brian and liver increased significantly with the in- crease of cadmium concentration, displaying obvious concentration effect relationship, which the correlation coefficient was 0.9660, 0.9630 and 0.9723, respectively. PCO content in various organs and tissues was distinctly higher than that of control group when exposure concentration varied between 0.686 and 2.059 mg＂ L- 1 cadmium. In the treatment of same concentration （0.686 mg＇L-l）, PCO content in gill, brian and liver tissues tended to raise with increasing exposure time. The sensitive order on cadmium in PCO content was liver 〉 gill 〉 brian. In conclusion, cadmium could cause protein oxi- dative damage in the viscera tissues, however, the extent of protein oxidative damage is different in organs; PCO content could be used as an effective biomarker for assessing the ecotoxicolo^ical effect of heavv metal nolh^tinn nn fi^h,~