B. The Fibrinolytic Mechanism The mechanism of fibrinolysis

Abstract

In recent years, stimulated by the production by the pharmaceutical industry of fibrinolytic agents suitable for therapeutic use in man, there has been a great increase in interest in the components and functions in health and disease of the fibrinolytic enzyme system. Development of knowledge of fibrinolysis Spontaneous lytic activity of blood clots It has been known for many years that human blood possesses fibrinolytic activity. Hunter (1794) records that in 'animals killed by lightning or by electricity’ or in animals 'who are run very hard, and killed in such a state’ the blood does not clot. This phenomenon was partly explained by Morawitz (1906) who found that the blood from victims of sudden death contained no fibrinogen and could destroy the fibrinogen and fibrin of normal blood. Denis (1838) observed that the blood clots obtained in wet cupping redissolved in less than 24 h. Green (1887) noted that when fibrin prepared from ox blood had dissolved when incubated in saline it could not be clotted again by thrombin. Dastre (1893), during the course of phlebotomy in dogs, observed a reduction in fibrin yield, which he attributed to destruction of fibrin, a process which he named ‘fibrinolysis’; and Hedin (1904) found spontaneous proteolytic activity in the globulin fraction of ox blood. The main outline of present-day knowledge of spontaneous fibrinolytic activity in the blood was finally achieved when Macfarlane (1937) showed that in man, fibrinolytic activity in the blood could be provoked by surgical operation.