Figure 3.

Enzymatic inhibition of GDXa and FXa by TFPI or antithrombin (AT). (A–B) For antithrombin inhibition, 1.25 nM of FXa (A) or GDXa (B) were incubated in the presence of increasing concentrations of antithrombin (0 to 500 nM) at 37°C. Aliquots were removed at different times (0 to 90 min) and added to PNAPEP 1025 chromogenic substrate. (C–D) Inhibition of FXa (C) or GDXa (D) activity by TFPI was analyzed by incubating 0.25 nM of the enzyme for 3 h at 25°C in buffer A in the presence of increasing concentrations of TFPI (0 to 30 nM for GDXa and 0 to 10 nM for FXa). Data are representative of two different experiments.