Sensitivity to Dioxin Decreases as Zebrafish Mature
- Authors
- Lanham, K.A., Peterson, R.E., and Heideman, W.
- ID
- ZDB-PUB-120314-16
- Date
- 2012
- Source
- Toxicological sciences : an official journal of the Society of Toxicology 127(2): 360-370 (Journal)
- Registered Authors
- Heideman, Warren, Peterson, Richard E.
- Keywords
- persistent organic chemicals agents, polycyclic aromatic hydrocarbons agents, aquatic toxicology environmental toxicology, transciption factors gene expression/regulation, aging reproductive & developmental toxicology, developmental toxicity, post-natal reproductive & developmental toxicology
- MeSH Terms
-
- Lethal Dose 50
- Myosin Light Chains/genetics
- Zebrafish/embryology
- Zebrafish/genetics
- Zebrafish/growth & development*
- PubMed
- 22403156 Full text @ Toxicol. Sci.
- CTD
- 22403156
The embryos of teleost fish are exquisitely sensitive to the toxic effects of exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). However, several lines of evidence suggest that adults are less sensitive to TCDD. To better understand and characterize this difference between early life stage and adults, we exposed zebrafish (Danio rerio) to graded TCDD concentrations at different ages. The LD50 for embryos exposed at 1 day post fertilization (dpf) was more than an order of magnitude lower than it was for juveniles exposed at 30 dpf. The latency between exposure and response also increased with age. Embryo toxicity was characterized by marked cardiovascular collapse and heart malformation, while juveniles exposed at 30 dpf had no detectable cardiovascular toxicity. In juveniles the effects of TCDD exposure included stunted growth, altered pigmentation, and skeletal malformations. Furthermore, the transcriptional profile produced in hearts exposed to TCDD as embryos had very little overlap with the transcriptional changes induced by TCDD at 30 dpf. The early cardiotoxic response was associated with fish exposed prior to metamorphosis from the larval to the adult body plan at approximately 14 dpf. Our results show conclusively that the developmental stage at the time of exposure controls the toxic response to TCDD.