engleski

Observational Study of Hepatic Cytochrome P-450 Protein Expression and Activity in Summer Flounder (Paralichtys dentatus) after Combination Ormetoprim-Sulfadimethoxine Treatment

The metabolism of aquaculture antibiotics on the piscine, hepatic cytochrome P450 system has not been defined. Ormetoprim-sulfadimetoxine (Romet-30) was incorporated in the fish feed. Fifty summer flounder were fed at 1% body weight per day and randomly sampled before and on days 1, 6, 10, 21 post treatment. Hepatic microsomes were prepared, protein concentration determined, and Western blotting performed with goat anti-rat CYP1A1 and rabbit anti-human CYP3A4 serum. Catalytic activities were measured using: 3-cyano-7-ethoxycoumarin (CEC), 7-benzyloxy-4-trifluoromethylcoumarin (BFC), resorufin benzyl ether (BzRes). Treatment induced CYP1A1 and CYP3A4 protein expression. Male fish had stronger signals than females. Dealkylation of CEC (CYP1A2) was significantly increased immediately post treatment. Romet-30® ) inhibited CYP3A4 activity measured by BFC metabolism, but induced BzRes-mediated CYP3A4 activity. The usefulness of mammalian antibodies for piscine P450 Western blotting was demonstrated. Also, hepatic P450 1A2 and 3A4 metabolism was quantifiable by modifying kits developed for mammalian microsomes.

P450; Romet-30; summer flounder

nije evidentirano