ERp5-deficient platelets have increased thrombotic tendency in vivo and enhanced thrombotic response after injection of tunicamycin. (A-B) Doppler tracing of blood flow after electrolytic injury to the carotid artery in ERp5^fl/fl (control) and Pf4Cre⁺/ERp5^fl/fl (CKO) mice (A) and time to occlusion after carotid electrolytic injury in control (gray) and CKO (red) mice (B); n = 6 to 11 per genotype. (C) Representative images of platelet (green) accumulation over time after laser injury of the mesenteric vein in a control and ERp5 CKO mouse injected with tunicamycin 24 hours prior. (D) Kinetics of mean ± SEM platelet accumulation over time as measured by fluorescence area and area under the curve (AU) of individual thrombi in control (gray) and CKO mice (red) after tunicamycin injection; n = 9 thrombi from 3 control mice and n = 13 thrombi from 4 CKO mice. (E) Kinetics of mean ± SEM platelet accumulation over time as measured by fluorescence area and AU of individual thrombi in control (gray) and CKO mice (red) after DMSO vehicle injection; n = 11 thrombi from 4 control mice and n = 13 thrombi from 4 ERp5 CKO mice, mean ± SEM, Student t test. ∗P < .05.