Figure S2 Synaptosomal mitochondria. Synaptosomal mito- chondrial respiration is not affected by age or IL-6 treatment. State 3 respiration was initiated by malate plus pyruvate (10 mM each) (ADP already present), state 4 respiration was measured after addition of the F0F1-ATPase inhibitor, oligomycin, and maximal respiration was measured after adding the uncoupling agent, CCCP. IL-6 treatment: Two IL-6 i.p. injections (5 mg/kg), separated by 12 hrs were administered to young and old animals before the groups were sacrificed 12 hrs later for synaptosomal isolation. Found at: doi:10.1371/journal.pone.0005518.s002 (10.03 MB TIF) Figure S3 PV-interneurons in PFC. A statistically significant decrease in PV-positive cell counts was observed in the prelimbic References 1. Krabbe KS, Pedersen M, Bruunsgaard H (2004) Inflammatory mediators in the elderly. Exp Gerontol 39: 687–699. 2. 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