Bender N, Seidl C, Weichert W, Breddin H K
Department of Internal Medicine, Division of Angiology, J.W. Goethe University, Frankfurt am Main, FRG.
Haemostasis. 1988;18 Suppl 3:23-32. doi: 10.1159/000215865.
In experiments with a laser thrombosis model in rat mesenteric venules, where laser beams induce defined injuries at the vessel endothelium, antithrombotic potency of low-molecular-weight (LMW) heparins was calculated by the number of laser injuries required to induce vessel occluding thrombi. The antithrombotic effect of various LMW heparins was measured at defined time intervals after subcutaneous application. Simultaneously, rat blood was collected and aXa and aIIa plasma levels were determined by chromogenic substrate assays. The antithrombotic effect calculated in the animal model lasted longer than 48 h after a single subcutaneous heparin injection whereas the anticoagulative effect measured as aXa or aIIa activity was measurable only within the first 6 h after subcutaneous application. LMW heparins showed an antithrombotic effect at dosages where no influence on the coagulation system could be demonstrated.
在大鼠肠系膜小静脉激光血栓形成模型实验中，激光束会对血管内皮造成特定损伤，通过诱导血管闭塞性血栓所需的激光损伤数量来计算低分子量（LMW）肝素的抗血栓效力。在皮下给药后的特定时间间隔测量各种LMW肝素的抗血栓作用。同时，采集大鼠血液，通过发色底物测定法测定血浆中Xa和IIa的水平。单次皮下注射肝素后，动物模型中计算出的抗血栓作用持续超过48小时，而以Xa或IIa活性衡量的抗凝作用仅在皮下给药后的最初6小时内可检测到。LMW肝素在对凝血系统无影响的剂量下显示出抗血栓作用。
