Figure 3

Lipopolysaccharide (LPS) induction of central and peripheral pro-inflammatory cytokines, as well as plasma corticosterone, occurs independently of serotonergic p38α MAPK expression. Quantitative PCR (qPCR) analyses of mRNA expression were assessed 1 h post saline (i.p.) or LPS (0.2 mg kg⁻¹, i.p.) injection. (a, b) Two-way analysis of variance (ANOVA) demonstrates significant LPS-induced elevation of spleen interleukin (IL)-1β (F_{1, 21}=20.43, P<0.001) and tumor necrosis factor (TNF)-α (F_{1, 28}=29.20, P<0.001) independent of genotype (nonsignificant genotype and interaction). N=5–11 per group. (c, d) Two-way ANOVA demonstrates significant LPS-induced elevation of midbrain IL-1β, (F_{1, 24}=8.70, P<0.01) and TNF-α (F_{1, 21}=42.63, P<0.01) independent of genotype. N=5–8 per group. (e) Two-way ANOVA demonstrates significant LPS-induced elevation of serum corticosterone (CORT); drug effect F_{1, 24}=15.56, P<0.01, independent of genotype. N=4–8 per group. *P<0.05; **P<0.01; ***P<0.001, Bonferroni post hoc tests.