Effect of MAGP1 deficiency on thrombotic occlusion of the carotid artery. (A) Blood flow in the common carotid artery was monitored continuously with an ultrasonic flow probe. Local endothelial injury was induced by application of a 540-nm laser beam to the carotid artery followed by injection of rose bengal dye (50 mg/kg) into the lateral tail vein. Shown is the time to occlusion of blood flow following injury. Error bars indicate mean plus or minus standard deviation (n = 8 for each group). **P < .005, *P < .05. (B) Representative blood flow recordings showing the delayed occlusion time and stochastic flow pattern in MAGP1^−/− animals. Rose bengal dye was injected at time = 0 minutes. (C) Infusion of recombinant MAGP1 re-establishes normal occlusion time in MAGP1^−/− mice. Recombinant bovine MAGP1 was injected into the tail vein as a single bolus 5 minutes before rose bengal injection. An equivalent bolus of saline served as the control. Error bars indicate mean plus or minus SD (n = 6 for each group).