Capparelli Mariana V, McNamara John C, Grosell Martin
Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto 14040-901 SP, Brasil.
Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto 14040-901 SP, Brasil; Centro de Biologia Marinha, Universidade de São Paulo, São Sebastião 11600-000 SP, Brasil.
Ecotoxicol Environ Saf. 2017 Sep;143:201-209. doi: 10.1016/j.ecoenv.2017.05.042. Epub 2017 May 24.
The effects of exposure to copper (Cu) on tissue Cu accumulation, on hemolymph osmotic, Na and Cl regulation, and on gill Na/K-ATPase (NKA) and carbonic anhydrase (CA) activities were evaluated in the fiddler crab Minuca rapax. Waterborne copper was delivered to the crabs at one of three salinities (seawater at 25‰ salinity [S] = isosmotic control; distilled water [<0.1‰ S] = hypo-osmotic medium; or 60‰ S = hyper-osmotic seawater) either for 5 days in a 0.5-cm water film containing 0, 50, 150, 250 or 500µg Cu/L with free access to a dry surface, or in crabs fully submerged for 5h at 0, 250 or 500µg Cu/L. In the crabs with free access to a dry surface, the highest Cu concentrations were found in the hemolymph and hepatopancreas with some accumulation in the gills; accumulation in the hemolymph and gills was enhanced in low salinity but was salinity independent in the hepatopancreas. Osmotic regulation was unaffected by Cu exposure; however Na and Cl hypo- regulation was impaired by Cu in 25 and 60‰ S. Gill NKA activity was stimulated 2-fold at 50µg Cu/L and markedly inhibited at 150µg Cu/L and above in 0 and 25‰ S. Gill CA was inhibited in <0.1‰ S but stimulated in 25 and 60‰ S; an inverse concentration-CA activity response was seen above 150µg Cu/L for all salinities. In the submerged crabs, Cu accumulated in all tissues in 60‰ S; however, there was no clear-cut Cu concentration-accumulation relationship evident in any tissue for either exposure regime, likely owing to the crabs' ability to regulate Cu. Copper exposure diminished osmotic, [Na] and [Cl] hypo-regulatory ability, especially in higher salinities. Gill NKA activity was markedly inhibited by Cu overall, and particularly above 250µg Cu/L in <0.1‰ S. Gill CA activity was inhibited in 25‰ S but inconsistently affected in 0 and 60‰ S. These findings show that Minuca rapax is affected both physiologically and biochemically by Cu contamination, although to different degrees, depending on the delivery regime, salinity, copper concentration and target tissue.
在招潮蟹敏捷招潮蟹（Minuca rapax）中评估了暴露于铜（Cu）对组织铜积累、血淋巴渗透压、钠和氯调节以及鳃钠/钾 - ATP酶（NKA）和碳酸酐酶（CA）活性的影响。在三种盐度之一（盐度为25‰的海水[S] = 等渗对照；蒸馏水[<0.1‰ S] = 低渗介质；或60‰ S = 高渗海水）下，将水中的铜以以下两种方式给予螃蟹：一种是在含有0、50、150、250或500μg Cu/L的0.5厘米水膜中暴露5天，螃蟹可自由接触干燥表面；另一种是将螃蟹完全浸没在0、250或500μg Cu/L的溶液中5小时。在可自由接触干燥表面的螃蟹中，血淋巴和肝胰腺中发现的铜浓度最高，鳃中有一定积累；血淋巴和鳃中的积累在低盐度下增强，但在肝胰腺中与盐度无关。渗透调节不受铜暴露的影响；然而，在25‰和60‰ S的盐度下，铜会损害钠和氯的低调节能力。在0和25‰ S的盐度下，鳃NKA活性在50μg Cu/L时被刺激2倍，在150μg Cu/L及以上时受到显著抑制。在<0.1‰ S的盐度下鳃CA受到抑制，但在25‰和60‰ S的盐度下受到刺激；在所有盐度下，150μg Cu/L以上均出现浓度 - CA活性的反向响应。在浸没的螃蟹中，在60‰ S的盐度下所有组织中都积累了铜；然而，对于任何一种暴露方式，在任何组织中都没有明显的铜浓度 - 积累关系，这可能是由于螃蟹调节铜的能力所致。铜暴露降低了渗透、[Na]和[Cl]的低调节能力，尤其是在较高盐度下。总体而言，鳃NKA活性受到铜的显著抑制，在<0.1‰ S的盐度下，特别是在250μg Cu/L以上时。在25‰ S的盐度下鳃CA活性受到抑制，但在0和60‰ S的盐度下影响不一致。这些发现表明，敏捷招潮蟹在生理和生化方面都受到铜污染的影响，尽管程度不同，这取决于给药方式、盐度、铜浓度和靶组织。
