Effect of LPS on mRNA expression of IDO (A), IL-1β (B), TNFα (C), IL-6 (D) and IFNγ (E) in the hypothalamus. Mice were injected i.p. with saline or LPS (830 μg/kg) and hypothalamus were collected 2, 6, 12 or 24 h after injection. Data represented the means ± SEM (n= 6). The * symbol represented statistical differences between saline and LPS groups, *p<0.05; **p<0.01; ***p<0.001. Bars labeled with different letters (a, b or c) are significantly different from each other (p<0.05). nd = no detectable.