INHIBITION OF Bothrops jararaca VENOM HEMORRHAGIC ACTIVITY BY FRACTION EA2MB FROM Croton urucurana BAILLON

Esmeraldino, L.E. Veronese, E.L.G., Ticli, F.K., Franco, J.J., Cintra, A.C.O., Sampaio, S.V.

Department of Clinical, Toxicological and Bromatological Analyses, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil

The aim of this work was to fraction the aqueous extract of de Croton urucurana and evaluated the neutralization of B. jararaca venom (BjV) hemorrhagic activity by fractions. The fractionation of the aqueous extract (AE) was performed on Amberlite column, using ethanol (Fraction EA2) and then water (fraction EA1) as eluent. The EA2 was dissolved in methanol, cleared by centrifugation and the resulting solution (EA2M) was further submitted to partition with water and butanol, which extracted fractions EA2MA and EA2MB, respectively. Antihemorrhagic and anticoagulant activities of these fractions against BjV were assayed according to Theakston and Reid (Bull. Word Health Organ. 61: 949-956, 1983). For the antihemorrhagic assays, BjV was added to fractions (1:20, w/w) and immediately injected i.d. in 90-110g Wistar rats. The hemorrhagic halos were analyzed using the computer program “Image tool”. For the anticoagulant assay, BjV was incubated whit fractions (1:20, w/w) for 1 h and 25 mL of the incubated with fractions to 200 mL of the plasma. The clotting time was measured up to the visualization of the first sings of fibrin. Fractions EA2MA e EA2MB inhibited 91.9 and 96.6%, respectively, of the effect of 2 MHD of BjV. this fractions did not increase the clotting time of MCD of BjV. Fraction EA2MB inhibited the hemorrhagic activity of 2 MHD of BjV at a ration of 20:1 (w/w) whit no effect on clotting time.

Financial support: CNPq and FAPESP.

CORRESPONDENCE TO:

Luis Everton Esmeraldino, Tenente Catão Roxo, 530 Apto. 4B, Ribeirão Preto, SP, CEP: 14051-140, Brasil, Email: luisee@usp.br