镉在鲤鱼组织内的蓄积及对血浆指标的影响

随着工业的迅速发展,水环境中的镉污染日趋严重,镉的蓄积性强,毒性高。为了进一步研究镉在鱼类不同组织内的蓄积及其对血浆指标的影响,以鲤鱼(Cyprinus carpio)为受试生物,设置3个浓度梯度,镉浓度分别为0(对照组)、5和50μg·L-1,试验周期为30d。结果显示,随着暴露时间的延长,染毒组鲤鱼鳃、肝胰脏和肾脏中镉蓄积量与对照组相比均显著升高(p<0.05),其中肾脏蓄积量最大,其次为肝胰脏和鳃,且50 μg·L-1染毒组各组织镉蓄积量显著高于5 μg·L-1染毒组(p<0.05);30d时,5和50 μg·L-1染毒组鳃、肝胰脏和肾脏中镉蓄积量分别为对照组的12.3和43.5倍、5.1和27.3倍、11.9和70.8倍;鲤鱼肌肉中仅检测到微量镉(0.02～0.04mg·kg-1),且暴露时间和镉暴露浓度不影响肌肉中镉的蓄积量。整个试验期间,各染毒组血浆中钙和磷含量、超氧化物歧化酶(SOD)活性、丙二醛(MDA)含量和谷草转氨酶(GOT)活性与对照组相比无显著差异(p>0.05)。研究表明,不同程度的水体镉污染均能造成鲤鱼各组织(肌肉除外)内较高浓度的镉蓄积,但对血浆指标无显著影响。

Cadmium Accumulation in Different Carp Tissues and Its Effect on Blood Plasma Indicators of Carps

With the rapid development of industry,cadmium(Cd) pollution is increasingly serious.Cadmium is highly toxic and readily accumulates in organisms.To investigate the cadmium accumulation in different fish tissues and its effect on blood plasma indicators,carps(Cyprinus carpio) were exposed to 0(control group),5 and 50 μg·L-1 Cd2+ for 30 days.Results showed that compared with the control group,the cadmium accumulation levels increased significantly in the gills,hepatopancreas and kidney with the extension of exposure time(p<0.05);the accumulation amount was maximum in kidney,followed by those in gills and hepatopancreas;the accumulation amount in 50 μg·L-1 Cd2+ treatment group was significantly higher than that in 5 μg·L-1 Cd2+ treatment group(p<0.05).At the end of 30 days,the accumulation amounts in the gills,hepatopancreas and kidney of carps exposed to 5 and 50 μg·L-1 Cd2+ were 12.3 and 43.5,5.1 and 27.3,11.9 and 70.8 folds of those in the control group.Only trace amount of cadmium(0.02-0.04 mg·kg-1) was detected in the muscles of carps,and the exposure time and cadmium concentration had no significant effect on the accumulation amount of cadmium in the muscles.During the exposure to cadmium,the blood plasma indicators,including calcium and phosphorus contents,superoxide dismutase(SOD) activity,malondialdehyde(MDA) content and glutamic oxalacetic transaminase(GOT) activity,had no significant differences compared with the control group(p>0.05).It was demonstrated that exposure to cadmium at different levels would cause high cadmium accumulation in different tissues(except muscles) of carps,but had little significant effect on the blood plasma parameters.