喹乙醇对鲤肝胰脏抗氧化酶系统的影响

Effects of dietary olaquindox on antioxidant enzymes system in hepatopancreas of Cyprinus carpio

用含不同剂量喹乙醇(0～3200mg·kg-1)的饲料饲喂鲤,分别对鲤在摄食3、6、9和12周时肝胰脏中超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH px)等抗氧化酶活性、脂质过氧化物丙二醛(MDA)含量及总抗氧化能力(T AOC)进行了测定。结果表明,SOD活性随饲料喹乙醇剂量的升高总体上呈升高的趋势,试验时间对各个处理组的SOD酶活性影响不大。饲料中喹乙醇对GSH px活性的影响较小,其剂量达1600mg·kg-1以上时GSH-px酶活性变化明显,主要表现为诱导效应。饲料中喹乙醇剂量的改变大体上不对MDA含量产生影响,且随时间的延长,除3200mg·kg-1组外,其余各实验组的MDA含量都有所降低。随喹乙醇剂量的增加和实验时间的延长,T AOC均呈现降低的趋势,其中以1600和3200mg·kg-1组的下降幅度最大。结果提示,高剂量下喹乙醇对抗氧化酶活性影响较大,并伴随着机体抗氧化能力的减弱。

Mirror carp Cyprinus carpio were fed diets containing different concentrations of olaquindox (0-3200 mg·kg^(-1)) for 12 weeks. Activities of two antioxidant enzymes such as superoxide dismutase(SOD) and glutathion peroxidase(GSH-px), levels of malondialdehyde (MDA) and total antioxidative competence (T-AOC) in hepatopancreas were determined every 3 weeks. SOD activities roughly increased with increasing olaquindox concentration, but didn't change greatly as feeding period was prolonged. Activities of GSH-px were not affected markedly by increasing olaquindox concentration and feeding period until above the dose of 1600 mg·kg^(-1). Also were MDA contents influenced in general with the change of olaquindox concentration in feed, however, decreased gradually when the period was lengthened except for a dose of 3200 mg·kg^(-1). T-AOC values declined with increasing olaquindox concentration and feeding period, and did to a very low level at above 1600mg·kg^(-1). From these results, it can be concluded that antioxidant enzyme activities are induced more significantly at relatively higher concentration of olaquindox than at lower concentration. Elevation of concentration of olaquindox in feed is accompanied by weakened antioxidative ability of carp.