Fig. 5.

(A) Lack of treatment effects on histone H4 acetylation in the distal colon of corn oil-fed rats. Data are means ± SEMs for eight rats per diet per treatment group (P > 0.05). For each rat, 15 well-oriented crypt columns were selected and each nucleus circled to determine the mean histone H4 acetylation stain intensity per rat. (B) Dietary butyrate increased the level of histone H4 acetylation in the distal colon of rats fed fish oil and injected with saline. In contrast, when rats were injected with AOM, fish oil and butyrate treatment decreased the level of histone acetylation as compared with fish oil and butyrate rats injected with saline. Data are means ± SEMs for eight rats per diet per treatment group. Bars with different letters are significantly different (P < 0.04).