Fig. 8

Interleukin-1 receptor antagonist (IL-1ra) reduces the anxiety-like phenotype in colitic mice but does not affect locomotion. To investigate the effect of colitis and IL-1ra on behavior, control and colitic female mice were implanted with intracerebroventricular cannulas above the right lateral ventricle and infused with either PBS or IL-1ra. At peak colitis, mice were assessed for anxiety-like behavior using the elevated plus maze. A In colitic mice, IL-1ra significantly increased the percentage time spent in the open arms of the maze (F(1, 29) = 5.0, *P = 0.01; n = 7–10 mice/group, two-way ANOVA). B In colitic mice, IL-1ra significantly decreased the percentage time spent in the closed arms of the maze (F(1, 29) = 4.0, *P = 0.021; n = 7–10 mice/group, two-way ANOVA) compared to colitic mice infused with PBS, indicating a decrease in anxiety-like behavior. C Total distance traveled in the elevated plus maze remained unchanged across each treatment condition (F(1, 29) = 0.12, P = 0.73; n = 7–10 mice/group)