sgp130 reduces IL-6 receptor activation, gene expression, and protein secretion in vivo. Hippocampal tissue was collected 8 h after ICV sgp130 and i.p. LPS and assayed for A) STAT3 phosphorylation, B) mRNA levels of IL-6¸IL-1β, and TNF-α, C) and IL-6 protein. sgp130 reduced LPS-induced STAT3 phosphorylation, mRNA levels of IL-6, but not IL-1β or TNF-α, and IL-6 protein in the hippocampus. Bars represent the mean ± SEM (n = 8-9) Means with different letters are statistically different from each other (P < 0.05).