镉污染对养殖刺参的毒性效应研究

Evaluation of Aquatic Cadmium on the Toxicological Effects of Cultured Holothurian （ Apostichopus japonicus ）

为探讨水体中镉污染对水产养殖造成的影响和机制，以刺参作为受试生物，研究重金属镉在不同暴露浓度和不周暴露时间条件下若干生化指标的变化。结果表明：随着镉暴露浓度增加，刺参组织和体腔液中超氧化物歧化酶（SOD）活性增加，乳酸脱氢酶（LDH）和碱性磷酸酶（AKP）活性降低，丙二醛（MDA）质量摩尔浓度升高，其中0．5mg／L处理组SOD诱导活性最高；随着暴露时间延长，镉对刺参体腔液中SOD，LDH和AKP活性下降的趋势更加明显，其中AKP活性动态变化最显著。AKP可作为重金属镉对刺参毒性效应的最佳酶学评价指标，在镉浓度低于0．5mg／L时可用于对刺参的拮抗调节。

In order to study the effects and mechanism of aquatic cadmium on aquaculture, some metabolic change was researched when the holothuria were exposed to cadmium chloride solution with different con centration and subjected to certain days respectively. The results indicate that, under the conditions of increased cadmium exposure, the SOD activity was enhanced, but both LDH activity and AKP activity reduced, and MDA contents rose in the coelomic fluid and body of holothuria, and the SOD activity was greatly induced by 0.5 mg/L cadmium treatment. The SOD,LDH and AKP activity in the coelomic fluid declined more apparently after holothuria were continuously exposed to cadmium solution, and also AKP activity showed continuous change most obviously. Therefore, AKP is the best enzyme for estimating toxicological effect of holothuria polluted by cadmium chloride, and holothuria can be regulated by anta nism as the cadmium concentration is lower to 0.5 mg/L.