Main features of the oxidative metabolism in gills and liver of Odontesthes nigricans Richardson (Pisces, Atherinopsidae)

M.E. LATTUCA; G.F. MALANGA; C. AGUILAR HURTADO; A.F. PÉREZ; J. CALVO; S. PUNTARULO

COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. PART B, BIOCHEMISTRY & MOLECULAR BIOLOGY.

Elsevier

Año: 2009 vol. 154 p. 406 - 411

1096-4959

The aim of this work was to study comparatively oxidative metabolism in the gills and the liver of a silverside, Odontesthes nigricans, in their natural environment, the Beagle Channel. Fish were collected with seine net at Cambaceres Bay (54°52´S, 67°16´W) in October 2007. Oxidative damage to lipids was evaluated by assessing TBARS and lipid radical content, in the gills and the liver. Gills showed a significantly higher damage than liver. The content of lipid soluble antioxidants, a-tocopherol and b-carotene, and catalase activity showed significantly higher values in the liver than in the gills. The A· content, measured by EPR, showed no significant differences between the gills and the liver of fish. AH- content, assessed by HPLC, were 12±2 nmol/mg FW in the gills, and 159±28 nmol/mg FW in the liver. Oxidative metabolism at the hydrophilic level was assessed as the ratio ascorbyl radical content (A·)/ascorbate content (AH-). The ratio A·/AH- was significantly different between organs, (6±2)10-5 and (5±2)10-6, for the gills and the liver, respectively. The ratio lipid radical content/lipid soluble antioxidants was significantly higher in gills as compared to the value recorded for the liver, suggesting an increased situation of oxidative stress in the lipid phase of the gills. Taken as a whole, O. nigricans liver exhibited a better control of oxidative damage than the gills, allowing minimization of intracellular damage when exposed to environmental stressing conditions.