Fig. 6. (A) CYP1A immunoreactivity (brown/black) in the tectum mesencephali of the control and ß-naphthoflavone (BNF)-treated lake trout. Hemorrhage depressed the immunoreactivity of CYP1A in BNF-treated juvenile lake trout. (B) Multifocal hemorrhage (brown) in the midbrain of the BNF-treated juvenile lake trout. Note that some blood cells have infiltrated into tissues. Black arrows indicate multinucleated white blood cells. Horizontal sections (20 µm thick) are counterstained with hematoxylin nuclear stain (purple). Scale bars, 100 µm.