Antithrombotic and haemorrhagic effects of the naturally occurring thrombin inhibitor hirudin.
Haemorrhagic effects of the naturally occurring thrombin inhibitor hirudin measured by the determination of bleeding time were compared with its antithrombotic actions in different models of experimental thrombosis. In mice and rats intravenous administration of hirudin caused a plasma concentration-dependent prolongation of bleeding time after transection of the tail tip and standardized incision of the tail, respectively. In rats intravenous infusion of hirudin prevented the formation of stasis-induced venous thrombosis of the jugular vein and the occurrence of thrombotic occlusion of the carotid artery after electrically induced damage of the vessel wall. Comparison of the haemorrhagic action of hirudin with its antithrombotic effectiveness showed that it caused haemorrhagic side effects only at plasma concentrations which are not required for the antithrombotic effects.
Kaiser
B
B
Institute of Pharmacology and Toxicology, Medical Academy Erfurt, GDR.
Markwardt
F
F
D000818:Animals; D005260:Female; D005343:Fibrinolytic Agents / Q000008:administration & dosage / Q000097:blood / Q000494:pharmacology*; D006470:Hemorrhage / Q000097:blood / Q000139:chemically induced*; D006629:Hirudins / Q000008:administration & dosage / Q000097:blood / Q000494:pharmacology*; D007275:Injections, Intravenous; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D051381:Rats; D011919:Rats, Inbred Strains; D013917:Thrombin / Q000037:antagonists & inhibitors*; D013918:Thrombin Time
D005343:Fibrinolytic Agents; D006629:Hirudins; D013917:Thrombin