title: Responses of free radical metabolism to air exposure or salinity stress, in crabs (Callinectes danae and C. ornatus) with different estuarine distributions.
abstract: The swimming crabs Callinectes danae and C. ornatus are found in bays and estuaries, but C. danae is more abundant in lower salinities, while C. ornatus remains restricted to areas of higher salinity. Experimental crabs of both species were submitted to: air exposure (Ae, 3h), reimmersion in 33‰ (control) sea water (SW) (Ri, 1h) following air exposure; hyposaline (Ho, 10‰ for 2h) or hypersaline (He, 40‰ for 2h) SW, then return to control 33‰ SW (RHo and RHe, for 1h). Hemolymph was sampled for osmolality and chloride determinations. Activity of antioxidant enzymes [glutathione peroxidase (GPX), catalase, glutathione-S-transferase] and levels of carbonyl proteins and lipid peroxidation (TBARS) were evaluated in hepatopancreas, muscle, anterior and posterior gills. In Ho groups, hemolymph concentrations were lower in both species, compared to He groups. C. danae displayed higher control activities of GPX (hepatopancreas and muscle) and catalase (all four tissues) than C. ornatus. C. ornatus presented increased activities of catalase and GPX in Ae, Ri, and He groups. Increased TBARS was seen in C. ornatus tissues (He group). The more euryhaline species displayed higher constitutive activities of antioxidant enzymes, and the less euryhaline species exhibited activation of these enzymes when exposed to air or hyper-salinity.
authors: Departamento de Fisiologia, Setor de Ciências Biológicas, Universidade Federal do Paraná, Curitiba, PR, 81531-980, Brazil. osmolab98@gmail.com
authors: Carolina A
authors: CA
authors: Freire
authors: Valéria G
authors: VG
authors: Togni
authors: Marcelo
authors: M
authors: Hermes-Lima
mesh_terms: D000818:Animals; D003386:Brachyura / Q000378:metabolism / Q000502:physiology*; D002374:Catalase / Q000378:metabolism; D002712:Chlorides / Q000097:blood; D017753:Ecosystem; D057075:Enzyme Assays; D005260:Female; D005609:Free Radicals / Q000378:metabolism*; D005880:Gills / Q000201:enzymology; D005979:Glutathione Peroxidase / Q000378:metabolism; D005982:Glutathione Transferase / Q000378:metabolism; D006458:Hemolymph / Q000737:chemistry; D043143:Hepatopancreas / Q000201:enzymology; D015227:Lipid Peroxidation; D008297:Male; D009132:Muscles / Q000201:enzymology; D009928:Organ Specificity; D009994:Osmolar Concentration; D010084:Oxidation-Reduction; D010100:Oxygen / Q000378:metabolism; D050050:Protein Carbonylation; D045483:Rivers; D054712:Salinity; D013312:Stress, Physiological; D014882:Water-Electrolyte Balance
chemical_list: D002712:Chlorides; D005609:Free Radicals; D002374:Catalase; D005979:Glutathione Peroxidase; D005982:Glutathione Transferase; D010100:Oxygen