Figure 8.

Regulatory effect of dexamethasone in RANKL‐induced inflammatory reactions in vivo and in vitro. Mice were treated orally with dexamethasone (DEX; 5 mg·kg⁻¹) for 10 days before the intranasal RANKL challenge. (a) The number of the nasal rubs that occurred in the 10 min after the RANKL intranasal provocation. Serum was isolated from blood and then assayed for (b) IgE, (c) histamine, (d) TSLP, (e) IL‐1β, (f) IL‐4, (g) IL‐5, and (h) IL‐13. Data shown are the means ± SEM from n = 5 mice per group. (i) HMC‐1 cells (3 × 10⁵) were pretreated with dexamethasone for 1 hr, then incubated with 10 ng·ml⁻¹ of RANKL for 24 hr. The production of TSLP was measured by elisa. Data are represented as the mean ± SEM with n = 5 per group. (j) HMC‐1 cells (3 × 10⁶) were stimulated with 10 ng·ml⁻¹ of RANKL for the indicated times. The activation of PI3K, phosphorylated ERK (pERK), and caspase‐1 was determined by Western blot analysis. ^# P < 0.05; significantly different from the untreated group. *P < 0.05; significantly different from the RANKL‐treated group