Investigación Clínica
versão impressa ISSN 0535-5133versão On-line ISSN 2477-9393
Resumo
BRAZON, Josmary et al. Effect of Tityus discrepans scorpion venom on global coagulation test: Preliminary studies.. Invest. clín [online]. 2008, vol.49, n.1, pp.49-58. ISSN 0535-5133.
Tityus discrepans (Td) scorpion venom modifies clotting times in humans. We studied the in vitro venom effect on partial thromboplastin time (PTT), prothrombin time (PT) and its direct clotting activity, using fresh human plasma and purified fibrinogen as substrates. Whole venom (WV) was fractioned with a Protein Pak 125TM molecular exclusion column (0.5 mL/min, CH3COONH4 20 mM, pH 4.7). Six fractions (F1 through F6) with retention times ranging from 12.8 to 31 min were obtained. WV (78 to 625 µg/mL) and fraction F1 (10 to 42.5 µg/mL), shortened PTT; WV (700 to 1000 µg/mL) and fraction F6 (16.5 to 700 µg/mL), prolonged PTT. WV (40 to 240 µg/mL) and fraction F2 (5 to 40 µg/mL), prolonged PT. No thrombin-like activity was found with this venom on human plasma or purified fibrinogen. Td venom contains procoagulant components, able to shorten PTT. In addition, the venom contains anticoagulant components which prolong PT and PTT.
Palavras-chave : PTT; PT; anticoagulant; procoagulant; Tityus discrepans.