Minocycline pretreatment attenuates LPS-induced mRNA levels of TLR2, IL-1β, IL-6, and IDO in the hippocampus of aged mice. Adult and aged mice were injected i.p. with vehicle or minocycline for three consecutive days. On the third day mice were challenged with saline or LPS i.p. and A) MHC II, B) TLR2, C) IL-1β, D) IL-6, and E) IDO mRNA levels were determined from hippocampus collected 4 h later. Bars represent the mean ± SEM (n = 8). Means with different letters (a, b, c, or d) are significantly different (P < 0.05) from each other.