FIGURE 2.

Thrombin-mediated inhibition of U937 adhesion is independent of PAR activation and requires proteolytic activity. Confluent M-SMCs were grown in DME/F-12 medium containing 10% FBS without or with poly(I·C) for 18 h at 37 °C. A, M-SMCs were treated with varying concentrations of bovine thrombin for 6 h at 37 °C prior to the adhesion assay. B, M-SMCs were treated with poly(I·C) for 18 h, prior to treatment with either thrombin (25 units/ml) or TRAP (100 μm) for 3 h prior to U937 cell adhesion. C, cells were treated with thrombin for the indicated duration in the presence or absence of PMSF prior to addition of U937 cells. (Mean data are shown with error bars representing ± S.E. between replicates (n = 3); *, p < 0.05; ***, p < 0.001.)