Figure 2
Involvement of PAR1 and PAR3 receptor in thrombin-induced HO-1 expression. (A) Osteoarthritis synovial fibroblasts (OASFs) (six OA lines) were treated with thrombin (3 U/ml), thrombin plus PPACK (30 nM), SFLLRN-NH2 (100 μM), TFRGAP-NH2 (100 μM), and GYPGQV-NH2 (100 μM) for 24 hours, and HO-1 expression was examined with qPCR. (B) Normal synovial fibroblasts (seven normal lines) were treated with thrombin (3 U/ml), SFLLRN-NH2 (100 μM), and TFRGAP-NH2 (100 μM) for 24 hours, and HO-1 expression was examined with qPCR. (C) Cells were transfected with PAR1, PAR3, PAR4, or control siRNA for 24 hours, and PAR receptor level was examined with Western blotting. (D, E) Cells (five OA lines) were transfected with PAR1, PAR3, PAR4, or control siRNA for 24 hours followed by stimulation with thrombin for 24 hours, and HO-1 expression was examined with Western blotting and qPCR. Results are expressed as the mean ± SEM. *P < 0.05 as compared with basal level. #P < 0.05 as compared with thrombin-treated group.