In cultured microglia, interleukin-10 (IL-10) attenuates the inflammatory response to lypopolysaccharide (LPS) but not that induced by exposure to ischemic conditions. Cultured microglia show selective inflammatory responses after stimulation either with 3-hour anoxia (group ‘A') or with 10 ng/mL LPS (group ‘LPS'). (A to F) Cytokine mRNA expression was evaluated by qRT–PCR analysis 6 hours after initiation of the challenge. (G to J) Cytokine concentration in the culture medium was also measured at 6 hours by ELISAs. (A, C, E, G, I) Treatment with recombinant murine IL-10 (10 ng/mL) does not attenuate the response to anoxia (group ‘A+IL-10'). (B, D, F, H, J) However, IL-10 strongly prevents the inflammatory response to LPS (group ‘LPS+IL-10'). Values were obtained in three independent cultures. Symbol * refers to comparison versus control, and symbol & refers to comparison versus either anoxia or LPS. One symbol: P<0.05, two symbols: P<0.01, and three symbols: P<0001. TNF-α, tumor necrosis factor-α.