中文摘要：

把铜锈环棱螺（Bellamya aeruginosa）暴露于3组不同成分的微藻悬浮液中[蓝藻组：只投喂产毒铜绿微囊藻（Microcystis aeruginosa）;混合藻组：50%四尾柵藻（Scenedesmus quadricanda）＋50%产毒铜绿微囊藻;对照组：只投喂四尾柵藻],用酶联免疫检测法（Enzyme-linked immuno sorbent assay,ELISA）检测藻液和螺肝组织中的藻毒素浓度。结果表明,藻液中包括藻相和水相的总微囊藻毒素（MCs）浓度分别为：蓝藻组（36.34±4.12）μg·L-1;混合藻组（18.69±2.12）μg·L-1;对照组未检出。在喂食暴露的前6h内,混合藻组和蓝藻组螺肝组织中微囊藻毒素含量持续增长,而后出现下降趋势;第12h更换藻液并将微藻浓度调整至初始值后,肝组织中MCs含量又迅速回升。同期螺肝细胞DNA损伤指标彗星尾长（TL）、彗星尾距（TM）和彗星尾部DNA百分含量（Tail DNA%）也随螺肝组织中MCs含量发生相应变化,各项DNA损伤指标均在产毒微囊藻喂食暴露6h时达到最大值,之后,各项指标值有所回落,但第12h更换藻液后,DNA损伤再次加剧。整个实验期间（24h）,混合藻组和蓝藻组的DNA损伤指标均显著高于对照组,混合藻组均显著高于蓝藻组。说明铜锈环棱螺经产毒微囊藻喂食暴露后,其肝组织细胞的DNA受到损伤,且螺肝组织MCs积累越多,DNA损伤越严重。

英文摘要：

Bellamya aeruginosa is one of the most common freshwater snails in China.It not only can ingest and digest bloom-forming cyanobacteria,but also enrich microcystins（MCs）from the cyanobacteria.Therefore it can be used as a potential indicator organism for monitoring MCs pollution.In this study,comet assay was used to detect the short-term toxic effects on the liver cell of B.aeruginosa under different levels of MCs exposure.B.aeruginosa was exposed to three different concentrations of MCs,respectively,presented in three different components of the microalgae suspension（Cyanobacteria group：MC-producing Microcystis aeruginosa only;mixed algal group：50% Scenedesmus quadricanda ＋50% MC-producing M.aeruginosa;and control group：S.quadricauda only）.Concentration of MCs in the microalgae suspension and the hepatic tissue of the snails was measured using the enzyme-linked immuno-sorbent assay（ELISA）.The average MCs concentrations of the microalgae suspension were（36.34±4.12）μg·L-1 for the cyanobacteria group,（18.69±2.12）μg·L-1 for the mixed algal group,and undetectable for the control group.The MCs concentration in the liver of B.aeruginosa continued to increase both in the cyanobacteria and the mixed algal groups,and reached the maxima at 6 h post-exposure,followed by a decline,however,it increased rapidly after the density of the algae was adjusted to the initial value at the 12th hour.The MCs concentration in the hepatic tissue of the mixed algae group was significantly higher than that of the cyanobacteria group,whereas the MCs was either below detection or in trace concentrations in the control group.Over the same period,the DNA damage indices [comet tail length（TL）,tail momen（tTM）and the percentage of comet tail DNA conten（tTail DNA%）] in the liver cells of B.aeruginosa changed correspondingly to the MCs concentrations in the hepatic tissue,and reached the maxima at 6 h post-exposure,followed by slight decline.However,the indices values increased again after the replacemen