Chen_2012_Environ.Toxicol.Chem_31_2338

The aim of the present study was to investigate the acute developmental neurotoxicity of polybrominated diphenyl ethers (PBDEs) in zebrafish larvae. From 2 to 120 h postfertilization zebrafish embryos were exposed to DE-71 (0, 31.0, 68.7, and 227.6 microg/L). The authors studied the locomotor behavior of larvae, involvement of the cholinergic system, and selected gene and protein expressions in the central nervous system. The results showed that low DE-71 concentration caused hyperactivity, whereas higher concentrations decreased activity during the dark period. During the light period, larval activity was significantly reduced in a concentration-dependent manner. In the cholinergic system, acetylcholinesterase activity significantly increased (10.7 and 12.4%) in the 68.7 and 227.6 microg/L exposure groups, respectively, and acetylcholine concentration accordingly decreased (60.5%) in the 227.6 microg/L exposure group. The mRNA expressions of genes encoding myelin basic protein, neuron microtubule protein (alpha1-tubulin), and sonic hedgehog a were significantly downregulated. Western blotting assay demonstrated that the protein concentration of alpha1-tubulin was also decreased. Overall, the present study demonstrated that acute exposure to PBDEs can disrupt the neurobehavior of zebrafish larvae and affect cholinergic neurotransmission and neuron development.