Figure 1. PAR2 is highly expressed in rat OA cartilage tissue and in IL-1β treated chondrocytes. (A) Representative H&E staining and immunofluorescence staining of PAR2 in rat knee articular cartilage from sham and PTOA model. (B) Quantitation of immunofluorescence staining of PAR2. (C, D) Representative western blots and quantification data of PAR2, Collagen II and Aggrecan in chondrocytes after stimulation with various dose of IL-1β for 24h. (E, F) Representative western blots and quantification data of PAR2, Collagen II and Aggrecan in chondrocytes after stimulation with 10ng/ml IL-1β under different time course. Data are shown as the mean ± SD. Significant differences between groups are indicated as ***P <0.001, **P < 0.01 and *P < 0.05.