Inhibitory effects on TF-triggered thrombin generation of the addition of FVa mutants to anticoagulant-deficient plasmas. FV mutants (WT, A2086D, W1920R, and R506Q) and no FV were incubated with thrombin (5 nM) for 30 minutes, and reactions terminated by the addition of hirudin (2.5 U/mL). The generated FVa (f.c. 4.5 nM) was added to plasma, followed by the measurement of thrombin generation after the addition of TF (5 pM) and PL (4 μM). (A) Representative thrombin-generation curves (Aa) and peak thrombin parameter (Ab) on the addition of FVa in pooled normal plasma are shown. Peak thrombin after the addition of FVa to (B) antithrombin (AT)-deficient, (C) PC-deficient, and (D) PS-deficient plasma are shown. Experiments were performed at least 3 times, and the average values ± standard deviations are shown. One-way analysis of variance was performed on experimental data.