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bioRxiv · 10.1101/2020.04.20.051508

Tissue accumulation and the effects of long-term dietary copper contamination on osmoregulation in the mudflat fiddler crab Minuca rapax (Crustacea, Ocypodidae)

Capparelli, M. V.·McNamara, J. C.·Grosell, M.
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Abstract

We examined copper accumulation in the hemolymph, gills and hepatopancreas, and hemolymph osmolality, Na+ and Cl- concentrations, together with gill Na+/K+-ATPase and carbonic anhydrase activities, after dietary copper delivery (0, 100 or 500 {micro}g Cu/g) for 12 days in a fiddler crab, Minuca rapax. In contaminated crabs, copper concentration decreased in the hemolymph and hepatopancreas, but increased in the gills. Hemolymph osmolality and gill Na+/K+-ATPase activity increased while hemolymph [Na+] and [Cl-] and gill carbonic anhydrase activity decreased. Excretion likely accounts for the decreased hemolymph and hepatopancreas copper titers. Dietary copper clearly affects osmoregulatory ability and hemolymph Na+ and Cl- regulation in M. rapax. Gill copper accumulation decreased carbonic anhydrase activity, suggesting that dietary copper affects acid-base balance. Elevated gill Na+/K+-ATPase activity appears to compensate for the ion-regulatory disturbance. These effects of dietary copper illustrate likely impacts on semi-terrestrial species that feed on metal contaminated sediments.

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Capparelli, M. V., McNamara, J. C., Grosell, M.. 2020-04-23. Tissue accumulation and the effects of long-term dietary copper contamination on osmoregulation in the mudflat fiddler crab Minuca rapax (Crustacea, Ocypodidae). https://doi.org/10.1101/2020.04.20.051508

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