COMPARISON OF THE EFFECTS OF DIFFERENT LOW-MOLECULAR-WEIGHT HEPARINS ON THE HEMOSTATIC SYSTEM ACTIVATION IN-VIVO IN MAN

In a double-blind, randomized, cross-over study the effects of single subcutaneous doses of 120 anti-Xa units/kg body wt, of three different low molecular weight heparin (LMWH) preparations were investigated in 15 healthy subjects by determination of thrombin-antithrombin III com plex (TAT), prothrombin fragment 1.2 (f1.2), and beta-thromboglobin (b eta-TG) in shed blood and in venous blood. Certoparin, dalteparin, and enoxaparin significantly inhibited coagulation activation marker form ation in shed blood. The substantial inhibition of TAT and f1.2. forma tion was slightly more pronounced in response to certoparin. beta-TG w as decreased following certoparin and enoxaparin, but not following da lteparin. However, no difference between groups was detectable. A smal l but consistent decrease of f1.2 formation in venous blood was noted for all LMWHs and daltrparin and enoxaparin, but not certoparin, inhib ited TAT formation. Only a minor impact of the three LMWH preparations was noted on beta-TC plasma concentrations. Our data indicate that th e studied LMWH preparations have a major impact on blood clotting in t he activated state and inhibit in vivo the hemostatic system to a comp arable extent.