Figure 1.

PAR-1 and PAR-2 are expressed and functional in RAW 264.7 macrophages. A. Western blot analysis on cell lysates of RAW 264.7 macrophages shows that macrophages constitutively express PAR-1 and PAR-2. B. Serum-starved cells (24 hours) treated with PBS, thrombin (1 U/mL), or trypsin (200 nmol/L) for 30 minutes. Western blot analysis of phospho-ERK1/2 indicates that expression of PAR-1 and PAR-2 in macrophages was functional. ERK1/2 phosphorylation is used as a surrogate marker for PAR-1 and PAR-2 activation. Protein loading was verified and normalized using β-actin.