Influence of dioxin and metal-contaminated sediment on phase I and II biotransformation enzymes in silver crucian carp.
Several biochemical responses were measured in silver crucian carp (Carassius auratus gibelio) after exposure to sediments obtained from contaminated Ya-Er Lake, No. 1 pond, and an unpolluted reference site, Honglian Lake. After 1 week of exposure, a significant induction of the phase I biotransformation enzyme (ethoxylresorufin-o-deethylase, EROD) was found (83-fold of control), whereas the phase II biotransformation enzyme (glutathione S-transferase, GST) exhibited a slight, but significant induction (1.4-fold of control) after 4 weeks of exposure. The level of cellular glutathione in the liver was also slightly elevated after 4 weeks of exposure. The delayed response of GST to the contaminants indicates that the phase I and phase II biotransformation enzymes are regulated differently in fish. The results suggest that EROD is a sensitive bioindicator to assess the toxicity of dioxin-contamined sediment in the laboratory.
State Key Laboratory of Freshwater Ecology and Biotechnology, Chinese Academy of Sciences, Wuhan, Peoples Republic of China.
G
G
Chen
Y
Y
Xu
L
L
Xu
Y
Y
Zheng
K W
KW
Schramm
A
A
Kettrup
D000818:Animals; D001711:Biotransformation; D002347:Carps / Q000378:metabolism*; D019363:Cytochrome P-450 CYP1A1 / Q000096:biosynthesis* / Q000187:drug effects / Q000378:metabolism; D004147:Dioxins / Q000494:pharmacology / Q000633:toxicity*; D004781:Environmental Exposure; D004790:Enzyme Induction; D019015:Geologic Sediments; D005982:Glutathione Transferase / Q000096:biosynthesis* / Q000187:drug effects / Q000378:metabolism; D008099:Liver / Q000187:drug effects / Q000201:enzymology; D014874:Water Pollutants, Chemical / Q000494:pharmacology / Q000633:toxicity*
D004147:Dioxins; D014874:Water Pollutants, Chemical; D019363:Cytochrome P-450 CYP1A1; D005982:Glutathione Transferase