Neurodevelopmental Defects in Zebrafish (Danio rerio) at Environmentally Relevant Dioxin (TCDD) Concentrations

• DOI: 10.1093/toxsci/kfg241
• Publication Date: 2003-11-10T20:12:51Z
• Authors: A. Hill
• Keywords: Danio; Neurotoxicity

Persistent ecotoxicants, such as dioxin and PCBs, are thought to pose one of the greatest threats public ecological health in industrial world. These compounds cause a range macroscopic malformations, particularly craniofacial apparatus cardiovascular system during vertebrate development. However, little is known about microscopic effects, especially on sensitive early life stages or molecular basis developmental neurotoxicity. Using zebrafish (Danio rerio), we have explored neurological deficits caused by early-life exposure environmentally relevant concentrations dioxin. We show, using quantitative stereological technique, that 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) substantially reduces capacity for embryonic brain development, causing 30% reduction total neuronal number 168-h larval brain. transgenic GFP-expressing lines, link this decreased expression key developmentally regulated genes, namely neurogenin sonic hedgehog. This disruption development provides understanding neurotoxic effects these compounds.