Fig. 3.

EROD activity (lines) and pericardial area (bars) of zebrafish larvae exposed to AhR agonists and hypoxia or normoxia. (A) Benzo[a]pyrene. EROD activity was induced by BaP and reduced under hypoxia (oxygen*BaP interaction: p<0.001). BaP had no effect on the size of the pericardium under normoxia, but induced pericardial edema under hypoxia (oxygen*BaP interaction: p<0.02). (B) Benzo[k]fluoranthene. EROD activity was induced by BkF and reduced under hypoxia (oxygen*BkF interaction: p<0.001). BkF did not induce pericardial edema under normoxia, however under hypoxia, severe pericardial edema was observed (oxygen*BkF interaction: p<0.001). (C) Pyrene. EROD was not measured in PY treated embryos due to high background fluorescence. Pericardial edema induced by PY was eliminated on co-exposure to hypoxia (oxygen*PY interaction: p<0.002). (D) PCB-126. EROD activity was induced by PCB-126 and reduced under hypoxia (oxygen*PCB interaction: p<0.001). Pericardial edema was induced in by high concentrations of PCB-126 under both normoxia and hypoxia, but there was no interaction (oxygen*PCB interaction: p=0.2). Treatments that do not share a letter are significantly different from one another in pairwise comparisons (p<0.05); uppercase letters refer to pericardial area measurements and lowercase letters refer to EROD measurements. Error bars are +/- standard error