GSK3 inhibitors enhance LPS-tolerance. (A, B) Mouse primary astrocytes were pretreated without (0) or with 100 ng/mL LPS (LPS) with or without GSK3 inhibitors 10 µM kenpaullone, 10 µM Chiron99021, or 10 µM TDZD-8 for 24 h, washed, and restimulated with 10 ng/mL LPS for 24 h and media from the second incubation were analyzed for IL-6 by ELISA. Values are shown as a percent of IL-6 production in the absence of GSK3 inhibitors. (C) Experiments were carried out as in A and B but GSK3 inhibitors were added only for the last 1 h of the first stimulation with LPS, and IL-6 was measured in the media after washing and restimulation with 10 ng/mL LPS for 24 h. (mean ± SEM; n=3–4; *p<0.05, ANOVA).