Arteriolar thrombosis in vivo. (a) Time to thrombotic arteriolar vessel occlusion in vivo, as measured in the ferric chloride superfusion model in the dorsal skinfold chamber in mice, was significantly accelerated when animals were treated with tumor necrosis factor alpha (TNFα) (5 ng/mL) for 4 hours. (b) Thrombus formation after injury with ferric chloride. The arrow is pointing at a thrombus, which is spared by the fluorescein-labeled plasma and almost occluding the vessel. *Significantly different versus sham-treated animals at P <0.05 (n = 8 to 10).