[Determination of the plasminogen level in rat plasma].

Content of plasminogen was estimated in rat blood plasma using streptokinase and human blood euglobulin fraction in order to activate plasminogen. By means of the procedure described the content of plasminogen was evaluated in blood of healthy animals and of the animals treated with tissue activator of plasminogen from pig heart.

[Thrombolytic properties of the heparin-tissue plasminogen activator complex and its effect on the fibrinolytic and coagulating systems of the blood in animals].

A complex heparin-tissue activator of plasminogen maintain its thrombolytic properties due to the presence of the activator. Studies of thrombolytic properties of the complex in vitro and of its effect in vivo on animal blood fibrinolytic and coagulation systems after intravenous administration confirmed this contention. After intravenous administration into animals the complex caused only slight effect on the system of fibrinolysis and inhibited moderately the coagulating activity of blood.

[Effect of synthetic and natural inhibitors on the activity of tissue activator from the swine heart in vitro].

Activity of tissue activator, isolated from pig heart, was studied in vitro in presence of synthetic inhibitors epsilon-aminocapronic acid and amben as well as of natural inhibitor contrical. All the inhibitors studied inhibited the tissue activator as shown by analyses on fibrin plates and by means of quantitative estimation of thrombolytic activity in fibrinolytic preparations in vitro. Among the two synthetic inhibitors amben exhitited the highest effect on the tissue activator: its effect was 3-4-fold higher as compared with epsilon-aminocapronic acid.

[Effects of epsilon-aminocaproic acid, amben and kontrikal on fibrinolysis due to tissue-type plasminogen activator from the pig heart].

Simultaneous intravenous administration to rats of epsilon-aminocaproic acid and high doses of plasminogen tissue activator from the pig heart was shown to prevent fibrinolysis changes induced by the tissue activator. Amben completely suppressed the action of the tissue activator at the blood concentration 15 times less than that of epsilon-aminocaproic acid. A greater effect of amben on the blood activator level was noted.