Test No. 250: EASZY assay - Detection of Endocrine Active Substances, acting through estrogen receptors, using transgenic tg(cyp19a1b:GFP) Zebrafish embrYos
OECD
Abstract
Agonist: A chemical/ligand that binds to and activates a specific nuclear receptor leading to the transcriptional activity of gene(s) regulated by the nuclear receptor.Antagonist: A chemical/ligand that binds to and blocks or inhibits the response mediated by agonist ligand.Anti-estrogenic activity: the capability of a chemical to suppress the action of 17β-estradiol mediated through estrogen receptors.Active test chemical: any test chemical that significantly induces the GFP expression with a minimum mean measured fold induction of GFP > 2 as compared to control. Bp: base pairBrain aromatase: the enzyme encoded by the cyp19a1b gene.The enzyme is responsible for the endogenous synthesis of estrogens.Cyp19a1b: the name of the gene that codes for the brain form of aromatase. tg(cyp19ab:GFP):it refers to the transgenic Zebrafish stably expressing a reporter gene (the Green Fluorescent Protein, GFP) under the control of the Zebrafish cyp19a1b promoter.DMSO: Dimethyl sulfoxide. Dpf: days post fertilizationEstrogenic activity: The capability of a test substance to mimic the action of 17β-estradiol in its ability to activate, in an ER-specific manner, the endogenous cyp19a1b and/or the GFP driven by the cyp19a1b promoter.EE2: 17α-ethinylestradiol. E2: 17β