Comparison of the In Vitro Anticoagulant Action of Proteases Secreted by the Micromycete Aspergillus ochraceus and Contained in Snake Venom

The in vitro anticoagulant action of proteases secreted by the micromycete Aspergillus ochraceus L-1 and contained in snakes’ venoms (Protac ® and RVV-X ® preparations) was studied. The severity of the action was shown of micromycete protease in relation to plasmas of humans and warm-blooded animals, as well as human plasmas deficient in certain factors of the hemostasis system, in comparison with snake proteases in reactions with chromogenic peptide substrates of activated protein C and factor X as well as using the activated partial thromboplastin time (APTT) test. The optimal time of preincubation of the micromycete A. ochraceus L-1 protease with human blood plasma (3 min) and the concentration of the chromogenic peptide substrate of activated protein C (from 0.1 to 0.5 mg/mL) necessary for the correct determination of protein C with its help was determined.