达氏鳇、施氏鲟及其杂交子代胚胎发育期的抗氧化酶活性

摘要

Fertilization rate and hatching rate of fertilized eggs and mortality of post-larvae were monitored and activities of antioxidant enzymes including acid phosphatase (ACP),alkaline phosphatase (AKP),superoxide dismutase (SOD) and catalase (CAT) were determined during embryonic development in Acipenser schrenckii,Huso dauricus and their hybrids by biochemical methods to evaluate the mechanism of heterosis.It was found that hybridization between Acipenser schrenckii and Huso dauricus showed high cross-compatibility with natural crossing progenies,indicating that the fertilization rate,hatchability and mortality of post-larvae were not affected by hybridization.Antioxidant enzyme activities were shown to be different patterns during embryonic development in A cipenser schrenekii and Huso dauricus and their hybrids.There were similar or higher antioxidant enzyme activities in the hybrid between Huso dauricus (9) × A cipenser schrenkii (♂) than those in their parents with higher antioxidant enzyme activity in some particular embryonic development stage.The hybrid between A cipenser schrenkii (♀) × Huso dauricus (♂) had significant lower SOD activity and glutathione (GSH) and malondialdehyde (MDA) contents than their parents did (P ＜ 0.05).The maximal SOD activity was observed at heart beating phase in A cipenser schrenkii and at yolk plug phase in Huso dauricus.The maximal SOD activity,however,was found at blastula phase in the hybrids.The findings indicate that the heterosis between Huso dauricus and Acipenser schrenkii can partially be explained by the differences in antioxidant enzyme activities among the sturgeons.%利用形态学和生物化学的方法测定达氏鳇Huso dauricus、施氏鲟Acipenser schrenckii及其正反杂交子代的受精率、孵化率、出苗率与胚胎发育期间超氧化物歧化酶(SOD)、过氧化氢酶(CAT)等抗氧化酶活性,分析胚胎发育与抗氧化酶含量的关系.结果表明,达氏鳇与施氏鲟为杂交亲和,可获得正常发育的正反交后代,不影响受精率、孵化率及出苗率.不同胚胎发育期鲟的4种主导抗氧化酶类型及变化规律各不相同.在特定发育时期,达氏鳇(♀)与施氏鲟(♂)正交子代(大杂交鲟)的CAT等抗氧化酶活性和丙二醛(MDA)含量均接近或高于两亲本中较高的一方;而达氏鳇(♂)与施氏鲟(♀)反交子代(小杂交鲟)介于两亲本之间,特别是SOD、还原型谷胱甘肽(GSH)活性和MDA含量显著低于其父母本.施氏鲟胚胎心脏搏动期SOD的活性最高,达氏鳇胚胎在卵黄栓期SOD的活性最高,而杂交子代的SOD活性均在囊胚期达最大值.综上所述,4种鲟胚胎发育时期内源性抗氧化酶活性的表达差异在一定程度上可解释物种间表型性状的差异.