Summary
Platelet-mediated thrombus formation at the site of vascular injury isa major trigger
for thrombo-ischemic complications after coronary interventions. The platelet collagen
receptor glycoprotein VI (GPVI) plays a critical role in the initiation of arterial
thrombus formation. Endothelial denudation of the right carotid artery in rabbits
was induced through balloon injury. Subsequently, local delivery of soluble, dimeric
fusion protein of GPVI (GPVI-Fc) (n=7) or control Fc (n=7) at the site of vascular
injury was performed with a modified double-balloon drugdelivery catheter.Thrombus
area within the injured carotid artery was quantified using a computer-assisted image
analysis and was used as index of thrombus formation.The extent of thrombus formation
was significantly reduced in GPVI-Fc- compared with control Fc-treated carotid arteries
(relative thrombus area, GPVI-Fc vs. Fc: 9.3 ± 4.2 vs. 2.3 ± 1.7, p<0.001). Local
delivery of soluble GPVI resulted in reduced thrombus formation after catheter-induced
vascular injury.These data suggest a selective pharmacological modulation of GPVI-collagen
interactions to be important for controlling onset and progression of pathological
arterial thrombosis, predominantly or even exclusively at sites of injured carotid
arteries in the absence of systemic platelet therapy.
Keywords
Angioplasty - glycoprotein VI - platelets - thrombosis - collagen