Imaging of prothrombinase constituents. Digital composite fluorescence and brightfield images of a representative thrombus acquired 3 minutes postinjury in HB mice infused with labeled Alexa₄₈₈-FV-810^SYA (green; 600 µg/kg), platelet antibody (red), and Alexa₆₄₇-FXa_i (cyan; 80 µg/kg); yellow (FV-810^SYA and platelets) or white (FV-810^SYA, FXa_i, and platelets) represent colocalization. (A) Red box covers core injury site; (B) red box covers upstream of injury. (A-B) Bar represents 10 µm. Time course fluorescence intensity for Alexa₄₈₈-FVa-810^SYA (green), Alexa₆₄₇-FXa_i (cyan), and platelets (red) either at the injury site (C) or upstream of the injury (D). Platelet accumulation was monitored using Alexa₅₅₅-labeled rat anti- CD41 F_(ab)2 antibody.