Department of Structural and Functional Biology, University of Naples Federico II, via Cinthia, 80126 Naples, Italy.
Ecotoxicol Environ Saf. 2011 May;74(4):984-8. doi: 10.1016/j.ecoenv.2011.01.013. Epub 2011 Feb 5.
Accumulated metals in soils negatively affect dwelling organisms. Earthworms, which are widespread and perform various essential functions, are able to accumulate metals that can damage the coelomic cells. The aim of this work was to evaluate the effect on Eisenia fetida lysosomal membrane stability both during and after copper exposure, and finally to link this to internal concentrations. E. fetida specimens were exposed to a reference soil and two Cu-spiked soils (35 and 350 mg kg(-1) d.w.) for 14 days (uptake period) and then transferred into the reference soil for other 18 days (elimination period). After 3 days of uptake, internal Cu concentrations increased and were higher in the specimens exposed to soils spiked with 350 mg Cu kg(-1) d.w. After 2 days of elimination, a strong decrease of internal Cu concentrations was always observed. The lysosomal membrane stability, measured as neutral red retention-times, was approximately 50 min for the earthworms exposed to the reference soils, whereas it decreased, at the end of the uptake period, to 21 and 13 min, respectively, for the organisms exposed to soils spiked with 35 and 350 mg Cu kg(-1) d.w. A full recovery of the lysosomal membrane stability was reached after 14 and 18 days of the elimination period, respectively, for the organisms exposed to soils spiked with 35 and 350 mg Cu kg(-1) d.w. The neutral-red assay would seem a good biomarker since the lysosomal membrane stability of E. fetida appeared to respond rapidly and strongly to soil copper contamination.
土壤中积累的金属会对居住生物产生负面影响。蚯蚓分布广泛，执行各种重要功能，能够积累可能破坏体腔细胞的金属。本工作旨在评估铜暴露期间和暴露后对赤子爱胜蚓溶酶体膜稳定性的影响，并最终将其与体内浓度联系起来。赤子爱胜蚓标本分别暴露于参考土壤和两种加铜土壤（35 和 350 mg kg(-1) d.w.）中 14 天（吸收期），然后转移到参考土壤中 18 天（消除期）。吸收 3 天后，体内铜浓度增加，暴露于含 350 mg Cu kg(-1) d.w.土壤中的标本中浓度更高。消除 2 天后，体内铜浓度总是强烈下降。溶酶体膜稳定性，用中性红保留时间测量，对于暴露于参考土壤的蚯蚓约为 50 分钟，而在吸收期结束时，分别暴露于加 35 和 350 mg Cu kg(-1) d.w.土壤中的蚯蚓降低至 21 和 13 分钟。暴露于加 35 和 350 mg Cu kg(-1) d.w.土壤中的蚯蚓在消除期分别经过 14 天和 18 天后，溶酶体膜稳定性完全恢复。中性红测定似乎是一种很好的生物标志物，因为赤子爱胜蚓的溶酶体膜稳定性似乎对土壤铜污染反应迅速且强烈。
