Fibrinolytic effect

Fibrinolytic effecting protease enzyme with glycoprotein structure relative mol mass ca. 30000. Isolation from the poison secretion (venom) of Agkistrodon rhodostoma (malayan pit viper) with chromatographic purification. 

Local intra-arterial thrombolysis (lAT) has several theoretical advantages over IV thrombolysis. For instance, by using coaxial microcatheter techniques, the occluded intracranial vessel is directly accessible and the fibrinolytic agent can be infused directly into the thrombus. This permits a smaller dose of fibrinolytic agent to reach a higher local concentration than that reached by systemic infusion, and ideally it allows for more complete recanalization with lower total doses of thrombolytic. With the smaller dose, complications from systemic fibrinolytic effects, including ICH, can theoretically be reduced. 

Garlic has been reported to have lipid- and blood-pressure-lowering properties, as well as antiplatelet, antioxidant, and fibrinolytic effects. In animal models and human cell cultures, it has been shown to have antiatherosclerotic activity (see Chapter 50). The sulfur-containing component, allicin, is considered to be the principal active ingredient of garlic, but several other bioactive ingredients have also been isolated. 

Tlte acylated enzyme does not react with the plasma inhibitors in the same way. However, it is obviously fixed to fibrin and deacylated there, so that the fibrinolytic effect remains restricted to the thrombus (Hg. 9). 

ASPIRIN DROTRECOGIN ALFA t risk of bleeding Additive effect on clotting mechanism drotrecogin alfa has antithrombotic and fibrinolytic effects Careful risk-benefit analysis should be undertaken if drotrecogin alfa is given within 7 days of aspirin... 

Simpson PJ, Radford SG, Forster SJ, et al. The fibrinolytic effects of anesthesia. Anesth Analg 1982 60 319. 

Although intrapleural streptokinase does not cause systemic fibrinolytic effects, there can be local fibrinolytic effects. In a case series describing the use of intrapleural streptokinase or urokinase in 26 patients, one developed major oozing from rib fractures sustained 1 month before therapy (89). This local bleeding required two thoracotomies. It is not clear from the report if streptokinase or urokinase was used in this patient, but streptokinase was used in most of patients in this series. Furthermore, the dose used was also not clear, with streptokinase doses of 100 000-750 000 lU. 

Fibrinolytic effects of garlic have also been evaluated. Garlic oil was shown to increase fibrinolytic activity by 55% (p <0.01) after 3 months of treatment, with 2 g twice daily for 3 months. Fibrinogen was not affected (24). A dried garlic preparation (Sapec) was shown to significantly increase tissue plasminogen activator activity compared to placebo after 1 day and 14 days of treatment (23). 

So far, the endogenous fibrinolytic enzyme plasmin could not successfully be used in thrombolysis because upon injection, it was immediately blocked by endogenous inhibitors, particularly by (X2-antiplasmin. Plasmin became fibrinolytically effective only after consumption of these inhibitors. To obtain a fibrinolytic effect, large quantities of plasmin were required, which in turn led to hyperplasminemia. This caused proteolytic degradation of fibrinogen and several clotting factors and hence hemordiagic complications. 

M. Verstraete, H. Bounameaux, F. de Cock, F. van de Werf, and D. J. Collen. Pharmacokinetic systemic fibrinolytic effects of recombinant human tissue-type plasminogen activator (rt-PA) in humans. Pharmacol. Exper. Ther. 255 506 (1985). 

Investigation of the fibrinolytic effects in 802 vivo (in rabbits) after subcutaneous implantation of the active immobilized enzyme... 

As for coagulation factors, the findings on the fibrinolytic effects of saturates are still inconclusive and need to be examined by more specific assays, measuring the activities of the separate fibrinolytic factors such as tPA and PAI-1. 

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