Comparison of the In Vivo Anticoagulant Properties of Standard Heparin and the Highly Selective Factor Xa Inhibitors Antistasin and Tick Anticoagulant Peptide (TAP) in a Rabbit Model of Venous Thrombosis

Summary

An in vivo thromboplastin (TP)-induced venous stasis thrombosis model in rabbits was used to compare the efficacy of standard heparin with the selective factor Xa inhibitors, recombinant tick anticoagulant peptide (rTAP) and recombinant antistasin (rATS), in prophylactic prevention of thrombus formation. Heparin significantly reduced TP-induced clot formation at doses of 55 and 100 U kg⁻¹ h⁻¹ yielding clot weights of 9 ± 4 and 6 ± 2%, respectively. Clot formation was significantly decreased by i.v. infusions of rTAP at doses of 21, 37 and 64 Μg kg⁻¹ min⁻¹ resulting in normalized clot weights of 13 ± 3, 8 ± 2 and 2 ± 1%, respectively. rATS was approximately 10-fold more potent than rTAP, reducing normalized clot weights to 16 ± 5, 2 ± 1 and 1 ± 0.8% at rATS doses of 1.25, 2.5 and 5.0 Μg kg⁻¹ min⁻¹, respectively. These data suggest that factor Xa-mediated inhibition of coagulation with rTAP and rATS is as effective as conventional anticogulant treatment with heparin in preventing venous thrombosis.

• REFERENCES

• 1 Rosenberg RD. Biochemistry of heparin antithrombin interactions, and the physiologic role of this natural anticoagulant mechanism. Am J Med 1989; 87 (Suppl. 03) 3B-2S-3B-9S
• 2 Choay J. Structure and activity of heparin and its fragments: an overview. Semin Thromb Hemostas 1989; 15: 359-364
• 3 Carter CJ, Kelton JG, Hirsh J, Çerskus A, Santos AV, Gent M. The relationship between the hemorrhagic and antithrombotic properties of low molecular weight heparin in rabbits. Blood 1982; 59: 1239-1245
• 4 Walenga JM, Fareed J, Petitov M, Samama M, Lormeav JC, Chogy J. Intravenous antithrombotic activity of a synthetic heparin pentasaccharide in a human serum induced stasis thrombosis model. Thromb Res 1986; 43: 243-248
• 5 Holmer E, Mattsson C, Nilsson S. Anticoagulant and antithrombotic effects of heparin and low molecular weight heparin fragments in rabbits. Thromb Res 1982; 25: 475-485
• 6 Cadroy Y, Harker LA, Hanson SR. Inhibition of platelet-dependent thrombosis by low-molecular weight heparin (Cy222): Comparison with standard heparin. J Lab Clin Med 1989; 114: 349-357
• 7 Haas S. An objective evaluation of the clinical potential of low molecular weight heparins in the prevention of thromboembolism. Semin Thromb Hemostas 1989; 15: 424-434
• 8 Albada J, Nieuwenhuis HK, Sixma JJ. Treatment of acute venous thromboembolism with low molecular weight heparin (Fragmin). Circulation 1989; 80: 935-940
• 9 Ockelford PA, Patterson J, Johns AS. A double-blind randomized placebo controlled trial of thromboprophylaxis in major elective general surgery using once daily injections of a low molecular weight heparin fragment (Fragmin). Thromb Haemostas 1989; 62: 1046-1049
• 10 Zanghi M, Morici V, Costanzo M, Astuto L, Salanitri G. Deep vein thrombosis of the legs: A new therapy by means of low molecular weight heparins. J Int Med Res 1988; 16: 474-484
• 11 Ockelford PA, Carter CJ, Mitchell L, Hirsh J. Discordance between the anti-Xa activity and the antithrombotic activity of an ultra-low molecular weight heparin fraction. Thromb Res 1982; 28: 401-409
• 12 Thomas DP, Merton RE, Barrowcliffe TW, Thunberg L, Lindhal V. Effects of heparin oligosaccharides with high affinity for antithrombin III in experimental venous thrombosis. Thromb Haemostas 1982; 47: 244-248
• 13 Buchanan MR, Bonev B, Ofosu F. The relative importance of thrombin inhibition and factor Xa inhibition to the antithrombotic effect of heparin. Blood 1985; 65: 198-201
• 14 Sturzebecher J, Sturzebecher U, Vieweg H, Wagner G, Hauptmann J, Markwardt F. Synthetic inhibitors of bovine factor Xa and thrombin comparison of their anticoagulant efficiency. Thromb Res 1989; 54: 245-252
• 15 Tidewell RR, Webster WP, Shaver SR, Geratz JD. Strategies for anticoagualation with synthetic protease inhibitors. Xa inhibitors vs thrombin inhibitors. Thromb Res 1980; 19: 339-339
• 16 Nutt E, Gasic T, Rodkey J, Gasic G, Jacobs JW, Friedman PA, Simpson E. The amino acid sequence of antistasin. J Biol Chem 1988; 263: 10162-10167
• 17 Dunwiddie C, Thornberry NA, Bull HG, Sardana M, Friedman PA, Jacobs JW, Simpson E. Antistasin, a leech-derived inhibitor of factor Xa. J Biol Chem 1989; 264: 16694-16699
• 18 Waxman L, Smith DE, Arcuri KE, Vlasuk GP. Tick anticoagulant peptide is a novel inhibitor of blood coagulation factor Xa. Science 1990; 248: 593-596
• 19 Neeper MP, Waxman L, Smith DE, Schulman CA, Sardana M, Ellis RW, Schaffer LW, Siegl PKS, Vlasuk GP. Characterization of recombinant tick anticoagulant peptide (TAP). J Biol Chem 1990; 265: 17746-17752
• 20 Nutt EM, Jain D, Lenny AB, Schaffer L, Siegl PKS, Dunwiddie C. Purification of recombinant antistasin a leech-derived inhibitor of coagulation factor Xa. Arch Biochem Biophys 1990 (in press).
• 21 Jordan SP, Waxman L, Smith DE, Vlasuk GP. Tick anticoagulant peptide: Kinetic analyis of the recombinant inhibitor with blood coagulation factor Xa. Biochemistry 1990 (in press).
• 22 Wessler S, Reimer SM, Sheps MC. Biologic assay of a thrombosis-inducing activity in human serum. J Appl Physiol 1959; 14: 943-946
• 23 Aronson DL, Thomas DP. Experimental studies on venous thrombosis: Effect of coagulants, procoagulants and vessel contusion. Thromb Haemostas 1985; 54: 866-870
• 24 Markwardt F, Hauptmann J, Nowak G, Kleben C, Walsmann P. Pharmacological studies on the antithrombotic action of hirudin in experimental animals. Thromb Haemostas 1983; 47: 226-229
• 25 Walenga JM, Pifarre R, Hoppensteadt DA, Fareed J. Development of recombinant hirudin as a therapeutic anticoagulant and antithrombotic agent: Some objective considerations. Semin Thromb Hemostas 1989; 15: 316-333
• 26 Klocking H-P, Markwardt F. Influence of recombinant hirudin on the thrombogenicity of prothrombin complex concentrates. Pharmazie 1989; 44: 341-342
• 27 Teitel SM, Rosenberg RD. Protection of factor Xa from neutralization by the heparin antithrombin-III complex. J Clin Invest 1983; 71: 1383-1391
• 28 Hauptmann J, Kaiser B, Nowak G, Stiirzebecher J, Markwardt F. Comparison of the anticoagulant and antithrombotic effects of synthetic thrombin and factor Xa inhibitors. Thromb Haemostas 1990; 63: 220-223