Bracht F, Schrör K
Institut für Pharmakologie, Heinrich-Heine-Universität Düsseldorf, Germany.
Agents Actions Suppl. 1995;45:315-22. doi: 10.1007/978-3-0348-7346-8_43.
Aptamer sequences were isolated from defibrotide, a single-stranded, commercial DNA preparation and studied for thrombin inhibitory activity. Three different aptamers were identified, sequenced and their biological activity was determined in platelet aggregation and coagulation assays. All aptamers were potent inhibitors of thrombin-induced platelet aggregation and thromboxane formation and prolonged the thrombin time in human plasma. There was no effect of any of these compounds when a thromboxane mimetic (U 46.1619), collagen or thrombin activating peptide (TRAP-6) were used as agonists, excluding a nonspecific binding of the compounds to the thrombin receptor. The data suggest that thrombin-inhibitory aptamers are present in the mammalian genome and may constitute an endogenous antithrombin system.
适体序列从去纤苷酸中分离得到，去纤苷酸是一种单链商业DNA制剂，并对其凝血酶抑制活性进行了研究。鉴定出三种不同的适体，对其进行测序，并在血小板聚集和凝血试验中测定其生物活性。所有适体都是凝血酶诱导的血小板聚集和血栓素形成的有效抑制剂，并延长了人血浆中的凝血酶时间。当使用血栓素模拟物（U 46.1619）、胶原蛋白或凝血酶激活肽（TRAP-6）作为激动剂时，这些化合物均无作用，排除了这些化合物与凝血酶受体的非特异性结合。数据表明，凝血酶抑制适体存在于哺乳动物基因组中，可能构成一种内源性抗凝血酶系统。
