Fu K, Izquierdo R, Vandevender D, Warpeha R L, Wolf H, Fareed J
Department of Surgery, Loyola University Chicago, Stritch School of Medicine, Maywood, IL 60153, USA.
Thromb Res. 1997 Jun 1;86(5):355-61. doi: 10.1016/s0049-3848(97)00080-7.
Low molecular weight heparins (LMWHs) are antithrombotic drugs composed of lower molecular weight components of heparin with an apparent molecular weight in the range of 4.0-8.0 KDA. These agents have been used clinically for several years. They have different mechanisms of action compared to heparin, a longer half-life and much higher bioavailability. Anticoagulant drugs such as heparin have been used topically in our previous studies to avoid bleeding complications observed with systemic administration. In this study, low molecular weight heparin (Certoparin, Sandoz) was topically administered in a rabbit ear arterial crush-avulsion thrombosis model and compared with heparin. The animals were divided into three groups: LMWH, heparin and saline control groups. In the LMWH group, the patency rate was 71% (10 of 14) at both 1 and 7 days. The patency rate in the heparin group was 95% (19 of 20) at 24 hrs and 80% (16 of 20) at 7 days. In the saline control group, the vessel patency rate was 17% at 24 hrs and 13% at 7 days. Clotting times such as ACT, PT and APTT performed on samples drawn one hour after drug administration were within the normal ranges for both the control and the treatment groups. The results suggest that topical administration of LMWH prevents the occurrence of thrombosis at the traumatic anastomosis site to a similar degree as heparin.
低分子量肝素（LMWHs）是由肝素的低分子量成分组成的抗血栓药物，其表观分子量在4.0 - 8.0千道尔顿范围内。这些药物已在临床上使用多年。与肝素相比，它们具有不同的作用机制、更长的半衰期和更高的生物利用度。在我们之前的研究中，已局部使用肝素等抗凝药物以避免全身给药时出现的出血并发症。在本研究中，将低分子量肝素（克赛，山德士公司）局部应用于兔耳动脉挤压 - 撕脱性血栓形成模型，并与肝素进行比较。动物被分为三组：低分子量肝素组、肝素组和生理盐水对照组。在低分子量肝素组中，第1天和第7天的通畅率均为71%（14只中的10只）。肝素组在24小时时的通畅率为95%（20只中的19只），在第7天时为80%（20只中的16只）。在生理盐水对照组中，血管通畅率在24小时时为17%，在第7天时为13%。给药后1小时采集的样本进行的活化凝血时间（ACT）、凝血酶原时间（PT）和活化部分凝血活酶时间（APTT）等凝血时间在对照组和治疗组中均在正常范围内。结果表明，局部应用低分子量肝素在预防创伤性吻合部位血栓形成方面与肝素的程度相似。
