Temporal changes of thrombus characteristics in Pecam-1^−/−and wild-type mice. Thrombus volumes (A), relative thrombus volume changes (B), thrombus lengths (C), cross-sectional areas (D), endothelial cell counts (E), macrophage counts (F), relative CD68 mRNA expression levels (G), and collagen deposition (H) on days 3, 7, 14, and 28 after vena cava ligation are shown (*P < .05, all means with ± standard deviations). Black symbols represent Pecam-1^−/− mice; white symbols represent controls.