中文摘要：

研究采用染毒→清除→二次染毒实验,研究了B[a]P对栉孔扇贝组织解毒代谢酶活力和DNA损伤的影响,筛选了栉孔扇贝在B[a]P胁迫下的生物标志物。结果表明：B[a]P对栉孔扇贝鳃丝、消化盲囊芳烃羟化酶（AHH）、谷胱甘肽硫转移酶（GST）活力和还原型谷胱甘肽含量（GSH）及DNA损伤影响显著（P〈0.05）,而对照组无明显变化。在一次染毒（0—15d）期间,除0.05μg/L B[a]P处理组鳃丝AHH活力与对照组无明显差异外,其他处理组组织AHH活力均被显著诱导,于15d时达到最大值,GST活力和GSH含量则呈逐渐下降趋势,5d时达到最小值,之后趋于稳定;而组织DNA链断裂（F值）基本呈下降趋势,DNA-蛋白质交联（DPC值）呈逐渐升高,至15d时分别达到最小值和最大值。在清除（15—45d）阶段,各处理组组织AHH活力逐渐下降,GST活力和GSH含量则逐渐升高,在25—40d时均恢复至对照组水平;各处理组组织F值和低浓度处理组（0.05、0.5μg/L）DPC值分别呈逐渐升高和下降趋势,于35—40d时恢复至对照组水平,而高浓度处理组（5、10μg/L）DPC值仍显著高于对照组水平。在二次染毒（45—60d）期间,除鳃丝AHH活力在50d时达到最大值外,其他指标变化趋势与一次染毒基本一致。由此可见,栉孔扇贝在B[a]P胁迫下组织解毒代谢酶活力和DNA损伤表现出明显的时间剂量效应性和稳定性,依据相关性分析,提出以鳃丝AHH活力和消化盲囊GST活力为防御型生物标志物,鳃丝、消化盲囊DPC值为损伤型生物标志物,并将AHH、GST活力和DPC值整合作为B[a]P毒性评定的组合型生物标志物,全面评价PAHs的污染毒性。

英文摘要：

Polycyclic aromatic hydrocarbons（PAHs） are ubiquitous environmental contaminants derived from incomplete combustion of carbon.As a pollutant,they are of concern because some compounds have been identified as carcinogenic,mutagenic and teratogenic.Benzopyrene（B[a]P） is a five-ring polycyclic aromatic hydrocarbon whose metabolites are mutagenic and highly carcinogenic.It is listed as a Group 1 carcinogen by the International Agency for Research on Cancer（IARC）.B[a]P is the most studied high molecular mass PAH and usually used as the model of PAHs.In China,environmental PAHs concentrations have been increasing day after day,particularly in aquatic environment.Therefore,more and more researchers pay attention to the toxic effects of PAHs/B[a]P on organisms and human health.Biomarkers are important tools for measuring of exposure to and effects of stressors that may arise at the molecular,cellular,physiological or behavioral level of an individual organism.Recently,they have been widely used to assess the effects of pollutants on aquatic animals.In present study,the effects of B[a]P on activities of detoxification metabolism parameters in gills and digestive glands of scallop Chlamys farreri were studied.At first,the clams were exposed to different concentrations of B[a]P（0.05,0.5,5 and 10 μg/L） for 15 days,and then they were cultured in normal seawater without B[a]P for 30 days.At last,the clams were treated with B[a]P for 15 days again.The experiment lasted for 60 days and the gills and digestive glands of the clams in control and different treatments were sampled at 0,5,10,15,20,25,30,35,40,45,50,55 and 60 day respectively.The activities of aryl hydrocarbon hydroxylase（AHH） and Glutathione S-transferase（GST）,the content of Glutathione（GSH）,DNA damaged and DNA-protein crosslinks（DPC） were tested by Spectrophotometry.The results indicated that the activity of AHH was significantly induced（P0 05） by B[a]P,while GST activity and GSH content decreased with the increase of B[a]P conce