Reduced thrombus stability of Orai1^−/− platelets in vivo. (A,B) Lethal pulmonary embolization after injection of collagen and epinephrine in anesthetized wild-type (+/+) and Orai1^−/− (−/−) mice. (A) Time to death through asphyxia. Each symbol represents one individual. (B) Occluded arteries in the harvested lungs per visual field. **P < .01. (C-F) Mechanical injury of the abdominal aorta of wild-type (+/+) and Orai1^−/− (−/−) mice was performed and blood flow was monitored with a Doppler flowmeter. Representative flow measurements (C), percentage distribution of irreversible occlusion (), unstable occlusion () and no occlusion (■) (D), time to final occlusion (each symbol represents one individual) (E), and representative cross-sections of the aorta 30 minutes after injury (F) are shown. Bars represent 100 μm. (G,H) FeCl₃-induced chemical injury of small mesenteric arteries from wild-type (+/+) and Orai1^−/− (−/−) chimeras. (G) Time to occlusion. Each dot represents one individual. (H) Representative fluorescent images before and 24 minutes after injury. Bar represents 50 μm.