Figure 4: Total β 2-AR expression in splenocytes from AA and non-AA rats at (a) D21 and (b) D28 after immune challenge. (a) Expression of β 2-AR was increased on D21 in splenocytes from SMB- and CFA-treated rats compared with Saline- and MO-treated rats. (b) In contrast, on D28, β 2-AR expression was significantly decreased in CFA-treated compared with all other treatment groups. (c) Representative immunoblot depicting β 2-AR expression in splenocytes from each treatment group on D28 after CFA challenge. Spleen cells were harvested, lysed, and proteins resolved by SDS-PAGE. The data were normalized to β-actin. Cellular extracts were probed with a β 2-AR receptor antibody to determine β 2-AR expression and quantified by densitometry. Each bar represents the mean optical density ± SEM with an of 8 rats per treatment group. Statistics: one-way ANOVA with Bonferroni multiple comparison tests. (*; **; ***).