Fig. 1

Mean (± SEM) IFN-γ (A), IL-1β (B), IL-4 (C), IL-5 (D), IL-6 (E), CXCL1 (F), IL-10 (G), IL-13 (H), TNF-α (I) levels in the ventral hippocampus after cognitive bias testing, normalized by total protein concentrations. Adolescent males had higher IFN- γ, IL-1β, IL-4, IL-5, and IL-10 levels compared to adolescent females and adult groups and higher IL-6 compared to young adult and middle-aged males. Adolescent and young adult females had higher IL-1β, IL-4, and IL-10 levels compared to middle-aged females. Middle-aged rats had higher CXCL1 levels compared to adolescents and young adults and higher TNF-α levels compared to young adults. Both adolescents and middle-aged adults had higher IL-13 levels than young adult rats. * indicates p < 0.05: compared to all other groups. & indicates p < 0.05: compared to middle-aged adults. # indicates p < 0.05: compared to young adult and middle-aged adults. @ indicates p < 0.05: main effects of age. n = 7–11. SEM = standard error of the mean