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A field study was conducted to assess the potential use of metallothionein (MT) and stress proteins as biomarkers of trace metal exposure. Shore crabs (Carcinus maenas) were collected from five sites: three located in the metal-contaminated Fal estuary (Southwest England) and two control sites located on the south coast of England. Two methods for determining MT levels in crab midgut gland were compared. A direct method in which MT was quantified by spectrophotometric measurement of SH content, and an indirect method in which the metal content (Cu and Zn) of partially purified MT was measured. Stress protein levels (stress-70) were quantified in crab gills using an improved western blotting technique. Elevated Cu and Cd concentrations compared to values in control crabs were found in the midgut glands of crabs from the Fal estuary. No significant variation was seen in Zn concentrations among the five sites. The two techniques used for MT analysis yielded similar results. Metallothionein concentrations were slightly higher in crabs from Restronguet Creek (the most metal-contaminated site) than in crabs from the other four sites, however this difference was not significant (p > 0.05). Stress protein levels did not reflect the metal gradient. 相似文献
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A. -K. Lundebye M. H. G. Berntssen S. E. Wendelaar Bonga A. Maage 《Marine pollution bulletin》1999,39(1-12):137-144
Three experiments were conducted with Atlantic salmon (Salmo salar) to assess the effects of dietary exposure to copper and cadmium. The results presented here provide an overview, details of each experiment will be published in full elsewhere. In the first experiment, salmon parr exposed for four weeks to 35 and 700 mg Cu kg−1 diet had significantly elevated intestinal copper concentrations, cell proliferation (PCNA) and apoptosis rates compared to control fish. No differences were observed in gill or plasma copper concentrations among the groups. In contrast to the controls, the Cu exposed groups did not grow significantly during the exposure period. The second experiment (three months exposure) was conducted to assess the effects of dietary copper (control, 35, 500, 700, 900 or 1750 mg Cu kg−1 diet) on growth and feed utilization in salmon fingerlings. Growth was significantly reduced after three months exposure to dietary Cu concentrations above 500 mg kg−1. Similarly, copper body burdens were significantly higher in fish exposed to elevated dietary copper concentrations (above 35 mg Cu kg−1 diet). In the third experiment, salmon parr were exposed to one of six dietary cadmium concentrations (0, 0.5, 5, 25, 125 or 250 mg Cd kg−1 diet) for four months. Cadmium accumulated in the liver>intestine>gills of exposed fish. Rates of apoptosis and cell proliferation in the intestine increased following exposure to dietary cadmium. Exposure to elevated concentrations of dietary cadmium had no effect on growth in salmon parr. Results from these studies indicate that cellular biomarkers have potential as early warning signs of negative effects on the overall fitness of an organism. 相似文献
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