Estudos hemostáticos secundários causados pela peçonha bruta, frações proteicas e proteínas isoladas da peçonha de Crotalus durissus terrificus

Abstract

Snakebites (Ophidism) are listed by the World Health Organization as a neglected tropical disease and are considered a public health problem. Among the activities triggered by envenoming from Crotalus durissus terrificus snake venom, the coagulant one is intriguing and contradictory, curious and contradictory, since the venom has, in its composition, coagulation precursor proteins and anticoagulant proteins. The present work describes, in vitro, the performance of crude venom, protein fractions and purified proteins of Crotalus durissus terrificus venom on the coagulation factors of human plasma secondary hemostasis. The coagulant and / or anticoagulant activity of crude venom, protein fractions and purified proteins were evaluated directly on human citrated plasma. Changes in Prothrombin Time (PT) and Activated Partial Thromboplastin Time (APTT) were measured with commercial kits. Clots formed in the presence of crude venom, protein fraction # 7 and Gyroxin displayed as a hyaline flexible mass and steady state. The evaluation of the clot formation time in the presence of the protein fractions # 1 to # 6 and isolated proteins (Crotoxin complex, Crotoxin A, Crotoxin B and Crotamine), after the commercial tests (PT and APTT), allowed to infer that these proteins interfere in all pathways of the coagulation cascade. Therefore, the Crotoxin A, Crotoxin B, Crotoxin and Crotamine proteins may act similarly to some anticoagulants direct inhibitors of thrombin, factor Xa and antithrombin III activator. Moreover, Crotoxin B can inhibits the formation of the prothrombinase complex by direct interaction with factor Xa. Consequently, the protein content from C. d. terrificus snake venom can act synergistically in coagulation and dysfunction and / or inhibition of natural anticoagulants unbalancing hemostasis.