Fig. 4
Peripheral LPS specifically increases expression of kynurenine producing enzyme, indoleamine 2,3-dioxygenase (IDO). mRNA fold changes (ΔmRNA) of IDO were assessed at 6 and 24 h following LPS injections in the (a) hippocampus, (b) amygdala, and (c) striatum. mRNA expression of IDO2 (left panel) and tryptophan 2,3-dioygenase (TDO, right panel) were also measured at 6 and 24 h post LPS in the (d) hippocampus, (e) amygdala, and (f) striatum. Data represent sample means ± SEM, n = 8–11 samples/group. #,* = overall significance or post hoc comparison to saline treatment group. # p < 0.1–0.05; *p < 0.05–0.01; **p < 0.01–0.001; ***p < 0.001