苯并(a)芘对蚯蚓细胞色素P450和抗氧化酶影响  

Effects of Benzo (a) pyrene on Cytochrome P450and antioxidant enzymes in Earthworms

作　　者：张薇[1,2] 宋玉芳[1] 刘淼[1] 孙铁珩[1] 

机构地区：[1]中国科学院沈阳应用生态研究所陆地生态过程重点实验室,辽宁沈阳110016 [2]沈阳农业大学土地与环境学院,辽宁沈阳110161

出　　处：《辽宁工程技术大学学报（自然科学版）》2009年第5期846-848,共3页Journal of Liaoning Technical University (Natural Science)

基　　金：财政部社会公益科研项目"绿色农业科学研究与示范(2007-10)"资助项目;国家科技支撑计划"农田有害物质循环阻控与消减关键技术研究(2007BAD89B03)"资助项目;沈阳农业大学青年教师科研基金资助

摘　　要：研究了苯并(a)芘(BaP)低剂量污染胁迫下对蚯蚓(Eisenia fetida)体内细胞色素P450酶系和抗氧化酶系的影响。通过滤纸接触染毒法,按指数递增设计暴露质量浓度为10-6到10-2mg·mL-1,染毒时间48h,检测指标分别为蚯蚓细胞色素P450含量、超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)活性。结果表明,在供试质量浓度范围内,蚯蚓体内P450含量和SOD活性与苯并(a)芘污染胁迫存在明显的响应关系,POD活性在BaP的最大暴露质量浓度下(10-2mg·mL-1)被显著诱导,而CAT活性对BaP暴露无明显的指示作用。这表明,BaP的代谢过程诱发了蚯蚓体内P450含量的增加,同时又抑制了SOD酶活性,从而使生物体对活性氧自由基的防御能力下降而更易受到毒害,这可能是BaP对生物体毒性作用的机制之一。The effects of Benzo（a） pyrene on cytochrome P450 and antioxidant enzymes of earthworms（Eisenia fetida） were studied to use these responses as biomarkers for monitoring PAH-contaminated soil in sublethal concentrations and to elucidate the possible metabolic mechanisms of BaP in earthworms.By contacting with contaminated filter paper,earthworms were exposed to the pollutant.The concentrations of pollutant were ranged from 10-6 to 10-2 mg/mL.After 48 hours’ exposure,the whole body of earthworm was used to detect total cytochrome P450 content,the activities of superoxide dismutase（SOD）,peroxidase（POD） and catalase（CAT）.Results showed that,within the test concentrations limits,total P450 content and SOD activity were very sensitive to the toxicity of Benzo（a） pyrene.POD activity was elevated only when earthworms exposed to the maximum BaP concentration（10-2mg.mL-1）.CAT activity did not show any response to BaP exposure.The results revealed that BaP metabolism in earthworm induced the increase of P450 content and also at the same time inhibited SOD activity.The decrease of SOD activity weakened the protection organism from the oxidative stress.This may be one of the mechanisms for BaP toxicity to organism.

关 键 词：苯并(A)芘 蚯蚓(Eisenia fetida) 细胞色素P450 抗氧化酶 生物标记物 

分 类 号：S154[农业科学—土壤学]