Pharmacologic inhibition of fibrinolysis does not increase venous thrombus mass or change cellular or fibrin(ogen) deposition in thrombi. Saline or TXA (600 mg/kg)–treated mice were subjected to IVC ligation. (A-B) The mass of venous thrombi harvested from wild-type mice after (A) 24 or (B) 6 hours. (C) Representative images of 24-hour thrombus sections probed to identify nuclei/DNA (DAPI [4′,6-diamidino-2-phenylindole], blue), platelets (anti-CD41, red), or fibrin(ogen) (polyclonal antibody, green). Scale bars indicate 100 μm. Methods for acquiring and processing images are provided in the supplemental Materials. (D) Quantification of nuclei, platelets, and fibrin(ogen) in 24-hour thrombi. (E) Representative images of 6-hour thrombus sections probed to identify nuclei/DNA (DAPI, blue), platelets (anti-CD41, red), or fibrin(ogen) (polyclonal antibody, green). Scale bars indicate 100 μm. (F) Quantification of nuclei, platelets, and fibrin(ogen) in 6-hour thrombi. Graphs show mean ± standard deviation or median ± interquartile range, as appropriate. Groups were compared by the unpaired t-test or the Mann-Whitney test for normally and nonnormally distributed data, as appropriate; no groups were significantly different.