Figure 1.

Plasma clot lysis with tissue plasminogen activator (tPA) or plasmin and inhibition by tranexamic acid (TXA). Plasma clots contained 2.5 nmol L⁻¹ tPA or plasmin as shown with a range of TXA concentrations, and times to 50% lysis were determined. Panel A shows representative raw data for clot lysis time‐courses for clots containing 2.5 nmol L⁻¹ tPA. Panel B shows analysis of lysis profiles as extension of time to 50% lysis at each TXA concentration used to calculate an IC₅₀ = 150 μmol L⁻¹ (± 20 μmol L⁻¹ as the standard error [SE] of the fit). Means and standard deviations [SDs] of duplicates are shown. Panel C summarizes lysis extension results as single‐point estimates for clot lysis curves where plasmin has been incorporated into the clots in place of tPA at the concentrations shown. Estimates of IC₅₀ values ranged from 4 to 41 μmol L⁻¹ TXA (SE for fitting was 0.3 μmol L⁻¹ at the lowest K_D up to 18 μmol L⁻¹ at the higher IC₅₀ values).