Effect of the Aqueous Extract of the Pentaclethra macroloba Against Snake Venom Bothrops atrox. 

^{1Da Silva, J.O.; 1Ticli, F.K.; 1Cintra, A.C.O.; 2Marcussi, S.; 3Proietti Jr, A.A.; 1Sant’Ana, C.D.; 1Mazzi, M.V.; 2Pereira, P.S.}; ²Soares, A.M. and ¹Sampaio, S.V.

1 Depto. de Análises Clínicas, Toxicológicas e Bromatológicas, FCFRP - USP, Ribeirão Preto, SP. 2 Unidade de Biotecnologia, UNAERP, Ribeirão Preto, SP. 3 Gerência de Projetos de Pesquisa, LACEN, Amapá.

The inhabitants of the Amazon region use, among others, the macerated bark of a plant  popularly called “Pracaxi” (Pentaclethra macroloba Willd) to combat the effects of snake bites. The snake Bothrops atrox is the responsible species for most of the snakebite accidents in this region. Bothropic accidents are characterized by hemorrhage, edema, necrosis and alterations in the coagulant system. In case of severe envenoming these effects can lead to complete destruction and subsequent loss of a limb or even death.  The overal toxicity of a venom is the consequence of the pharmacological action of its differents components and the response of the envenomed organism. In this present study were avaliated the effects of the aqueous extract of P. macroloba (AE) against lethal activity induced by B. Atrox venom. Doses of venom were injected i.m. in male swiss mice for the determination of the median lethal dose (LD50) through PROBITOS method. For the induction of the lethality, animals received 2 LD50 of the venom i.m. In the inhibition test, solutions containing a misture of crude venom (49.4 mg/Kg) and AE (25 or 50 mg/Kg) were injected in males swiss mice, without pre-incubation. Other group received venom i.m. and AE intra-peritoneally (i.p.), in the same concentrations. Control groups received only AE (12.5-1000 mg/Kg/ 50 mL PBS) or only venom by route i.m. The numbers of animals deads and livings were registered 24 hours after the administration. The LD50 of venom B. atrox was 24.7 ± 7 mg/Kg. AE dose of 25 mg/Kg exibited protection against venom, when administred mixed with them by route i.m. The survival rate of mice to 25 mg/Kg dose was 33.4% and to 50 mg/Kg dose was 44.4%. AE doses administred by route i.p. did not inhibit the venom lethal activity. The animals that received only AE (12.5 to 300 mg/Kg) by route i.m., did not have death. In conclusion, the results from this study demonstrated that AE show ability to significantly neutralize the lethal effect of the Bothrops atrox venom.

Support by: CNPq, FAPESP, CAPES and UNAERP.

Correspondence to: accintra@fcfrp.usp.br