VCL treatment delayed the onset of unstable thrombus formation and prevented the stable thrombus formation. (A) The tracings are representative of blood flow in FeCl3-treated exposed carotid arteries of wild-type mice. The tail veins of these mice were injected with either saline (10 μL/g of body weight) or a saline solution of VCL (4.8 μg/g of body weight). Their blood flow was monitored for 45 minutes, including a 3-minute treatment starting at zero time with a strip of filter paper soaked in 10% FeCl3. The arrow indicates the time of removal of the FeCl3-containing strip of filter paper. (B) Box-plot graphs represent time of first occlusion of carotid arteries (blood flow less than 0.2 mL/min) from 6 WT mice given injections of saline and 6 WT mice given injections of VCL. The results show that the median time required for the first thrombotic occlusion in 6 WT mice treated with saline was 3 minutes, with a range of 2 to 4 minutes; the median time required for the first thrombotic occlusion in the WT mice treated with VCL was 17 minutes, with a range of 12 to 45 minutes. Arterial blood flow was occluded in all the WT mice treated with saline at the end of the monitoring period. Blood flow in all of WT mice treated with VCL was patent at the end of 45 minutes, but the stable thrombus formation occurred after 65 minutes. These results demonstrate VCL treatment delayed the onset of thrombus formation and prevented the stable thrombus formation during the 45-minute observation period. Therefore, it is clear that stable thrombus formation in the FeCl3-treated carotid arteries is GPIbα dependent. Bars represent extreme values for times of first occlusion.
