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The zebrafish as a model organism for evaluation of endocrine disrupters

Örn, Stefan (2006). The zebrafish as a model organism for evaluation of endocrine disrupters. Diss. (sammanfattning/summary) Uppsala : Sveriges lantbruksuniv., Acta Universitatis agriculturae Sueciae, 1652-6880 ; 2006:28
ISBN 91-576-7077-3
[Doctoral thesis]

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Abstract

Many of the natural, pharmaceutical and industrial chemicals that are present in the aquatic environment can interfere with the endocrine system of fish. There is a demand for sensitive and robust test systems for risk assessment of the endocrine disrupting chemicals (EDC). The aim of this thesis was to develop a partial life-cycle test to be used for evaluation of EDC. The test was based on exposure of juvenile zebrafish to EDC during the period of gonad transformation and differentiation. The main endpoints studied were the induction of the estrogenic biomarker protein vitellogenin (Vtg) and gonad development. Zebrafish were exposed to single model substances to investigate if exposure during the period of gonad transformation and differentiation affects Vtg production and gonad development. Exposures to the synthetic estrogen 17α-ethinylestradiol (EE2) resulted in a dose-dependent increase in Vtg production, as well as female-biased sex ratios, including all-female stocks. Exposures to the androgens 17α-methyltestosterone (MT) and 17β-trenbolone (Tb) resulted in decreased Vtg concentrations, as well as male-biased sex ratios, including all-male stocks. In a comparative study with Japanese medaka a higher sensitivity of both Vtg and sex ratio of the zebrafish was shown after exposure to EE2 and Tb. Exposures to binary mixtures of the differently acting substances EE2 and Tb demonstrated that effects on both Vtg and gonad development can be detected. Application of this zebrafish partial life-cycle test on a chemically complex pulp mill effluent revealed both estrogenic and androgenic effects. In conclusion, the zebrafish respond to EDC at environmentally realistic concentrations. The results support that zebrafish is a suitable model species for evaluation of EDC.

Authors/Creators:Örn, Stefan
Title:The zebrafish as a model organism for evaluation of endocrine disrupters
Year of publishing :April 2006
Volume:2006:28
Number of Pages:39
Papers/manuscripts:
NumberReferences
ALLI. S. Örn, H. Holbech, T.H. Madsen, L. Norrgren, and G.I. Petersen (2003) Gonad development and vitellogenin production in zebrafish (Danio rerio) exposed to ethinylestradiol and methyltestosterone. Aquatic Toxicology 65:397-411 II. S. Örn, S. Yamani, and L. Norrgren (2006) Comparison of vitellogenin induction, sex ratio and gonad morphology between zebrafish and Japanese medaka after exposure to 17α-ethinylestradiol and 17β-trenbolone. Archives of Environmental Contamination and Toxicology, accepted for publication III. S. Örn, H. Holbech, and L. Norrgren (0000) Effects on vitellogenin production and gonad development in zebrafish (Danio rerio) exposed to mixtures of 17β-trenbolone and 17α-ethinylestradiol. Manuscript IV. S. Örn, A. Svenson, T. Viktor, H. Holbech, and L. Norrgren (2006) Male-biased sex ratios and vitellogenin induction in zebrafish (Danio rerio) exposed to pulp mill effluent. Archives of Environmental Contamination and Toxicology, accepted for publication
Place of Publication:Uppsala
ISBN for printed version:91-576-7077-3
ISSN:1652-6880
Language:English
Publication Type:Doctoral thesis
Full Text Status:Public
Agrovoc terms:fishes, animal models, chemicals, endocrinology, endocrine glands, sex ratio, vitellogenins, environmental impact
Keywords:zebrafish, Danio rerio, endocrine disrupters, gonad development, sex ratio, vitellogenin
URN:NBN:urn:nbn:se:slu:epsilon-1031
Permanent URL:
http://urn.kb.se/resolve?urn=urn:nbn:se:slu:epsilon-1031
ID Code:1089
Department:(VH) > Dept. of Biomedical Sciences and Veterinary Public Health
Deposited By: Stefan Örn
Deposited On:12 Apr 2006 00:00
Metadata Last Modified:02 Dec 2014 10:09

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