INDUCTION OF HEME OXYGENASE IN FISH BY HEAVY-METALS, PHENYLHYDRAZINE AND HIGH LIPID DIETS

Heme oxygenase (HO) was measured in fish liver and spleen by a coupled catalytic assay and by immunochemical analysis using an anti-mouse HO -1 antibody. In Atlantic salmon (Salmo salar) treated i.p. with cadmiu m, arsenite and phenylhydrazine, increased levels of HO activity and H O-cross-reacting protein were observed in liver microsomes. In the spl een, although no HO activity could be detected, increased levels of HO -cross-reacting protein Mere detected bit western blotting. The cross- reacting protein in liver and spleen had a relative molecular weight o f approx. 30 kDa, slightly lower than the mammalian counterpart. Pn ma ckerel (Scomber scombrus) fed a high lipid diet, increased levels of H O activity were observed in a continuously fed group compared with fis h starved for 2 months and wild mackerel. The results indicate that HO may be developed into a diagnostic biomarker for certain heavy metals and oxidative stress in fish. This application relies on the producti on of fish-specific antibodies for this enzyme. (C) 1998 Elsevier Scie nce Ltd. All rights reserved.