Journal: Toxicological Sciences
Article Title: PCB126 Exposure Disrupts ZebraFish Ventricular and Branchial but Not Early Neural Crest Development
Figure Lengend Snippet: Two methods of rescuing the PCB126 heart phenotype. (A–C) show 96 hpf wholemount, lateral views of control (A), PCB126-exposed (B) and PCB126/pifithrin-α cotreated (C) Tg( cmlc2 ::GFP) fish, incubated in DAR-4M (red) to label the bulbus arteriosus. Morphology and alignment of the heart structures are restored by pifithrin-α. The jaw phenotype is also rescued by pifithrin-α as seen in lateral views of Alcian blue–stained control (D), PCB126-exposed (E) and PCB126/pifithrin-α cotreated (F) fish. ep, ethmoid plate; M, Meckel's cartilage; cb, ceratobranchials. (G) Quantitative RT-PCR on whole fish lysates showing induction of cyp1a RNA in response to PCB, pifithrin-α, and a combination of the two. Data are represented as % increase of message over controls. Rescue by pifithrin-α appears to be due to competitive inhibition of PCB126 at AHR. (H–K) Ventral views of 72 hpf embryos treated with control morpholino (H, I) or tnnt2 morpholino (J, K) treated with DMSO (H, J) or PCB126 (I, K). The tnnt2 morphant hearts appear larger in both DMSO and PCB treatment groups. (L) Area measurements indicating that chamber size is the same or larger in tnnt2 morphants even when the embryos are exposed to PCB126 (Control-MO/DMSO, n = 7; Control-MO/PCB, n = 11; tnnt2 -MO/DMSO, n = 54; tnnt2 -MO/PCB, n = 57).
Article Snippet: To monitor development of the smooth muscle component of the cardiac outflow tract (the bulbus arteriosus), live control and PCB-exposed Tg( cmlc2 ::GFP) zebrafish at various stages were transferred from fish water directly into a 10μM solution of DAR-4M (Calbiochem, San Diego, CA) in fish water adjusted to pH 7.0, and incubated overnight in the dark.
Techniques: Fluorescence In Situ Hybridization, Incubation, Staining, Quantitative RT-PCR, Inhibition