RAPID COMMUNICATION Vitronectin Inhibits the Thrombotic Response to Arterial Injury in Mice

Vitronectin (VN) binds to plasminogen activator inhibitor-1 (PAI-1) and integrins and may play an important role in the vascular response to injury by regulating fibrinolysis and cell migration. However, the role of VN in the earliest response to vascular injury, thrombosis, is not well characterized. The purpose of this study was to test the hypothesis that variation in vitronectin expression alters the thrombotic response to arterial injury in mice. Ferric chloride (FeCl3) injury was used to induce platelet-rich thrombi in mouse carotid arteries. Wild-type (VN 1/1, n 5 14) and VN-deficient (VN 2/2, n 5 15) mice, matched for age and gender, were studied. Time to occlusion after FeCl3 injury was determined by application of a Doppler flowprobe to the carotid artery. Occlusion times of VN 2/2 mice were significantly shorter than those of VN 1/1 mice (6.0 6 1.2 minutes v 17.8 6 2.