Fig. 2

Chronic Epi stimulation inhibits cAMP production and activates FLSs through β₂AR. A Intracellular cAMP production induced by ISO (100 nM) stimulation in normal rat FLSs that were treated with ISO (1 μM) in the presence or absence of CGP (1 μM), ICI (1 μM) or 100 nM SR overnight was detected in the FRET system. B Intracellular cAMP production in normal or CIA rat FLSs treated with Ter (10 μM), (10 μM), or ISO (1 μM) was detected in the FRET system. C The intracellular cAMP concentration in FLSs from normal or CIA rats treated with Ter or ISO was determined by a kit. D The effect of knocking down β₂AR on FLS viability was detected by a CCK-8 assay. E, F The effects of knocking down β₂AR on FLS migration were determined by a Transwell assay, and the data were analysed. Scale bar, 100 μm. G, H The effects of knocking down β₂AR on FLS invasion were determined by a Transwell assay, and the data were analysed. Scale bar, 100 μm. The data are presented as the means ± SEMs; *p < 0.05, **p < 0.01, ***p < 0.001; n = 5 animals per group