蚯蚓（Eiseniafetida）细胞色素P450及抗氧化酶系对环境浓度苯并（a）芘的响应

以赤子爱胜蚓（Eiseniafetida）为供试生物，草甸棕壤为供试土壤，以蚯蚓微粒体细胞色素P450含量、抗氧化酶系以及谷胱甘肽转移酶活性为指标，进行了土壤中苯并（a）芘B（a）P]暴露与酶活性的量-效关系研究。结果表明，在接近沈抚灌区实地污染状况B（a）P（0．1～2．0mg·kg-1）暴露下，第1、3、7以及第14d取样时，P450和SOD有较好的响应：SOD在第1、3d显著升高，而在第7、14d时降低；P450总体表现为低浓度B（a）P诱导下降低，高浓度下升高的趋势。CAT、POD以及GST的敏感性相对较差。比照其他4个指标，蚯蚓P450的敏感性更为优异，具有较好的应用前景。指标敏感性总体表现为：P450〉SOD〉CAT／POD〉GST。

Influence of Benzo（a） Pyrene on Cytochrome P450 and Antioxidant Enzymes in Earthworms（Eiseniafetida）

Earthworms are common in a wide range of soils and are one of the most suitable bioindicator organisms for identifying the presence of chemical pollutants in soils. Analyzing P450 enzyme activities in earthworms is a newly developed practice for soil pollution risk assess- ment. We investigated the effects of benzo（ a ）pyrene （B （a）P） at different concentrations and exposure times on the biochemical responses of the Cytoehrome P450, superoxide dismutases （ SOD ）, gnaiacol peroxidases （ POD ）, eatalase （ CAT ）and Glutathione -S-transferases （ GST）in the earthworm（Eiseniafetida）. Results showed that low concentration of B （a）P（0.1-2.0 mg·kg-1 ）, similar to the real contamination condition of Sbenfu irrigation area in Shenyang, caused P450 and SOD to change significantly. SOD increased after the 1st and 3rd day of treatment and decreased after one and two weeks of treatment. P450 generally exhibited a decrease in activity when treated with O. 1 mg· kg-1 B （ a）P and in- creased with higher doses of the pollutant. P450 exhibited a positive dose-response relationship to B（ a ）P, making it a useful tool for risk as- sessment work. Change to SOD activities indicated superoxide damage in earthworms. B（ a ）P caused CAT to change only after 7th days of treatment, indicating a delayed response of CAT. POD also had significant response in the 7th day and this indicated that B（a）P might dam- age the antioxidase system. In summary, P450 was more sensitive than the other four indicators and more suitable for the diagnosis of soil pol- lutants. The sensitivity of the indicators could be ranked in order of most to least effective as follows： P450〉SOD〉CAT/POD〉GST.