A technique to investigate microvascular mural thrombus formation in arteries and veins: II. Effects of aspirin, heparin, r-hirudin, and G-4120.
After a standardized trauma to carotid arteries or femoral veins of hamsters, the antithrombotic effects of two antiplatelet agents (aspirin and the glycoprotein IIb/IIIa antagonist G4120) and two anticoagulants (heparin and the direct thrombin inhibitor r-hirudin) were studied in vivo. The thrombus area volume was assessed by image analysis of the transilluminated experimental vessels. Heparin, r-hirudin, and G-4120 demonstrated a dose-dependent complete inhibition of arterial and venous thrombosis. In contrast, the antithrombotic effect of aspirin was only partial in both vessel types. A significant correlation between activated partial thromboplastin time (aPTT) at the end of the experiments and the antithrombotic effect was observed with the anticoagulant agents. However, only r-hirudin inhibited thrombus formation at a therapeutical prolongation of aPTT, while heparin required supratherapeutical amounts to achieve the same inhibition. The data confirm that the inhibition of aspirin, heparin, r-hirudin, and G-4120 on the formation of platelet-rich thrombi is independent of the blood flow rate.
Stockmans
F
F
Center for Molecular and Vascular Biology, University of Leuven, Belgium.
Stassen
J M
JM
Vermylen
J
J
Hoylaerts
M F
MF
Nyström
A
A
D000818:Animals; D000925:Anticoagulants / Q000627:therapeutic use*; D001241:Aspirin / Q000627:therapeutic use*; D002341:Carotid Artery Thrombosis / Q000209:etiology / Q000517:prevention & control*; D006224:Cricetinae; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D005268:Femoral Vein; D006493:Heparin / Q000627:therapeutic use*; D024764:Hirudin Therapy; D016014:Linear Models; D008297:Male; D010314:Partial Thromboplastin Time; D010456:Peptides, Cyclic / Q000627:therapeutic use*; D010975:Platelet Aggregation Inhibitors / Q000627:therapeutic use*; D013454:Sulfoxides / Q000627:therapeutic use*; D013927:Thrombosis / Q000209:etiology / Q000517:prevention & control*
D000925:Anticoagulants; D010456:Peptides, Cyclic; D010975:Platelet Aggregation Inhibitors; D013454:Sulfoxides; C074915:G 4120; D006493:Heparin; D001241:Aspirin