Figure 3

Light photomicrographs of CYP1A mRNA labelled mid intestine (MI) of Atlantic salmon (A) Negative control (sense). No CYP1A staining and only nuclear staining can be seen (B) Control group (antisense). CYP1A staining with faint and low mRNA levels especially in the basal area of the intestinal folds (C) Exposed group (antisense). CYP1A staining with strong and high mRNA levels especially in the basal area and the apex area of the intestinal fold. Inside the cells CYP1A are located at and around the nucleus. In the photographs CYP1A mRNA levels can be seen with a dark colour and all cell nuclei with a green staining. All pictures are stained with the nuclear stain; methyl green.