Natural modulation of hepatic metallothionein and cytochrome P4501A in flounder, Platichthys flesus L.

Primary cultured cells as sensitive in vitro model for assessment of toxicants-comparison to hepatocytes and gill epithelia

“…It should be mentioned that the measured gill epithelia EROD activity in this study is much lower than those in cultured gill epithelia from seawater-adapted tilapia (Zhou et al, 2005). Hylland et al (1998) studied the natural modulation of hepatic EROD in flounder (Platichthys flesus L.) and found that season contributed significantly to the model for EROD. Jönsson et al (2003) showed that there was also a significant difference in the EROD activity that was induced by ␤-naphthoflavone (␤-NF) in Atlantic salmon smolts (Salmon salar) that were held in seawater or freshwater.…”

Metallothionein-2 gene from the mandarin fish Siniperca chuatsi: cDNA cloning, tissue expression, and immunohistochemical localization

“…The possible reason is that some other factors, including gender, age, heavy metal concentration, induction time, exposure route (injection or natural exposure) and accumulated metal concentrations in tissues after fish were induced also play important roles in determining Cd 2+ toxicity (Goksoyr et al, 1996;Hylland et al, 1998;Rotchell et al, 2001;Serafim and Bebianno, 2001;Vasconcelos et al, 2002;Knapen et al, 2007). More studies are required in order to acquire further evidence that explains the influence of all these factors.…”

“…Therefore, considerable efforts have been focused on the use of MT for monitoring metal contamination in water or in fish (Hermesz et al, 2001;Van Der Oost et al, 2003;Tom et al, 2004;Amado et al, 2006;Wu et al, 2007). However, tissue MT levels and metal contents in fish are influenced by age, season, sex, and species, e.g., in the flounder (Platichthys flesus), hepatic MT had the highest levels during the autumn in a year and increased significantly with age; in the mature female squirrelfish (Holocentrus adsencscionis), the MT mRNA and protein level increased at the onset of sexual maturation compared to immature females and males; the milkfish (Chanos chanos) had a higher tolerance to Cd exposure than either tilapia (Oreochromis mossambicus) or Acrossocheilus paradoxus (Goksoyr et al,1996;Hylland et al, 1998;Rotchell et al, 2001; Thompson et al, 2002;Wu et al, 2007). Even difference existed between isoforms and tissues, e.g.…”

Relationships Between Physiology, Tissue Contaminants, and Biomarker Responses in Atlantic Cod (Gadus morhuaL.)

“…The importance of such confounding factors differs for each biomarker; for cytochrome P-4501A (CYP4501A) activity in fish it is well known that there is a seasonal variation (Dewaide & Henderson, 1970;Hylland et al, 1998Hylland et al, , 2006aLarsen et al, 1992;Rotchell et al, 1999), that the response may differ for males and females (Förlin & Haux, 1990), with age (Sleiderink et al, 1995) or following starvation (Wall & Crivello, 1999). The response of other biomarkers such as metallothionein (MT) levels and δ-aminolevulinic acid dehydratase (ALA-D) activity were also found to be affected by sex or season in marine fish species (Hylland et al, 1998;Rotchell et al, 2001). Problems with some of the confounding factors just listed may be overcome by adhering to strict protocols, especially regarding the time of sampling, which need to be outside periods of high reproductive activity (including gonad buildup).…”