Test No. 250: EASZY assay - Detection of Endocrine Active Substances, acting through
estrogen receptors, using transgenic tg(cyp19a1b:GFP) Zebrafish embrYos
The EASZY assay is a mechanism-based in vivo screening assay designed to detect endocrine
active chemicals acting as agonist through estrogen receptors (ERs), by inducing the
expression of the green fluorescent protein (GFP) driven by the cyp19a1b promoter.
The EASZY assay allows for the detection of estrogenic activity of chemicals on transgenic
tg(cyp19a1b:GFP) Zebrafish embryos exposed for 96 hours during the embryonic stages
of development. At the end of the experiment, the fluorescence of each newly hatched
eleutheroembryo is measured using fluorescence microscope. Because the skull of early
developmental stages of zebrafish is transparent, GFP is observed, imaged and quantified
in vivo. The intensity of fluorescence is then quantified using image analysis software.
Published on June 17, 2021Also available in: French
In series:OECD Guidelines for the Testing of Chemicals, Section 2: Effects on Biotic Systemsview more titles