Dettori A G, Tagliaferri A, Dall'Aglio E, Pini M
V Divisione di Medicina Generale, Ospedale Regionale di Parma, Italy.
Int Angiol. 1988 Jul-Sep;7(3 Suppl):7-18.
The anticoagulant effect of a Low Molecular Weight Heparin from Alfa Farmaceutici, Bologna, Italy, was studied in human volunteers of either sex. Assays of plasma anti Xa (S-2222) and anti IIa (cromozym TH) activities, and of PTT, were performed following single or repeated administration by intravenous (i.v.), subcutaneous (s.c.) or intramuscular (i.m.) route. Each set of experiments was carried out in groups of subjects ranging from 6 to 12. After i.v. adm. of 8000 and 16000 I.U. AXa peak level and half life in plasma of the anti Xa activity were about double than the corresponding values of anti IIa activity and the effect on PTT, when compared with the same reference material (heparin, Third Internat. Standard). Similar differences between these pharmacological effects were found in the response curves obtained after s.c. or i.m. adm. of 16000 and 8000 I.U. Appreciable anti Xa activity was found in plasma 16-20 hours after adm. of 16000 I.U., and 10 hours after 8000 I.U. After repeated i.m. or s.c. adm. for 7 days, no cumulative effect was observed with 16000 I.U. once daily. By giving 8000 b.i.d., mean peak levels of .35-.40 U/ml of anti Xa activity were reached in the first day and of .45-.55 U/ml in the following days, a residual activity in the order of .1-.2 U/ml being always detected in the samples drawn immediately before the following injection.
对意大利博洛尼亚阿尔法制药公司生产的一种低分子量肝素在不同性别的人体志愿者中的抗凝作用进行了研究。通过静脉内（i.v.）、皮下（s.c.）或肌肉内（i.m.）途径单次或重复给药后，进行了血浆抗Xa（S-2222）和抗IIa（色酶TH）活性以及部分凝血活酶时间（PTT）的测定。每组实验在6至12名受试者中进行。静脉注射8000和16000国际单位后，与相同参考物质（肝素，第三国际标准品）相比，血浆中抗Xa活性的AXa峰值水平和半衰期约为抗IIa活性及对PTT影响的相应值的两倍。在皮下或肌肉注射16000和8000国际单位后获得的反应曲线中也发现了这些药理作用之间的类似差异。注射16000国际单位后16 - 20小时以及8000国际单位后10小时，在血浆中发现了明显的抗Xa活性。肌肉或皮下重复给药7天，每天一次给予16000国际单位未观察到累积效应。每天两次给予8000国际单位，第一天抗Xa活性的平均峰值水平达到0.35 - 0.40 U/ml，随后几天达到0.45 - 0.55 U/ml，在下次注射前立即采集的样本中始终检测到残留活性约为0.1 - 0.2 U/ml。
