Metallothionein induction by Cu, Cd and Hg in Dicentrarchus labrax liver: Assessment by RP-HPLC with fluorescence detection and spectrophotometry

Laboratoire de Biochimie et de Toxicologie Environmentale, Institut Supérieur d'Agronomie de Chott-Mariem, 4042 Sousse, Tunisia.
Marine Environmental Research (Impact Factor: 2.33). 06/2008; 65(4):358-63. DOI: 10.1016/j.marenvres.2008.01.002
Source: PubMed

ABSTRACT Metallothionein was quantified in sea bass Dicentrarchus labrax intraperitoneally (i.p.) injected with different Cu, Cd and Hg doses (50-250 microg kg(-1) wet wt) after 48 h exposure. A distinct peak with 16.8 min retention time was obtained by reversed-phase high performance liquid chromatography coupled to fluorescence detection (RP-HPLC-FD) with the three metals. Total metallothionein levels assayed in unheated liver extracts by RP-HPLC-FD were significantly higher (1.3-1.95-fold) than those obtained by the well-established spectrophotometric method. In the RP-HPLC-FD method, metallothionein increased linearly with Cu and Hg doses, being saturated beyond 100 mug kg(-1) Cd. Maximum induction was obtained at 100 microg kg(-1) Cd (5.3-fold), and 250 microg kg(-1) Cu or Hg (8- and 5.1-fold, respectively). At low doses no metallothionein induction was shown by the less sensitive spectrophotometric assay.

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