Measuring plasma protein extravasation in vivo. (A) Representative images of a thrombus formed in a mouse cremaster venule showing platelets (blue) and flash-activated cAlb (green). Each image is taken directly after an activating pulse of 405 nm light. (B) Time course of average platelet (black) and fibrin (white) area (n = 24; ± standard error of the mean [SEM]). (C) For a separate data set we tracked average platelet area (black) and P-selectin–positive area (white) (n = 23; ± SEM). (D) Time course of the combined average of relative cAlb extravasation (n = 47; ± SEM error bars too small to be visualized). (E) A dot plot of the relative cAlb extravasation for each injury at 200 seconds postinjury (n = 47). Plts, platelets; RFU, relative fluorescence units.