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Poster 250. Congresso da Sociedade Brasileira de Toxinologia, 8., Symposium of the Pan American Section of the International Society on Toxinology, 8., 2004, Angra dos Reis, Brasil. Abstracts... J. Venom. Anim. Toxins incl.Trop. Dis., 2004, 10, 3, p.609. |
Toxinology of Venoms from the South American Colubrids Philodryas olfersii and Philodryas patagoniensis
1Prudêncio, L.; 1Souza Filho, S.P.; 2Mello, S.M.; 1Prianti Jr, A.C.G.; 1Ribeiro, W.; 1Lopes-Martins, R.A.B.; 3Puorto,G.; 4Hyslop, S. and 1Cogo, J.C.
1 Serpentário do Centro de Estudos da Natureza, IP&D, UNIVAP, São José dos Campos, SP; 2 Centro de Controle de Intoxicações (CCI-HC), UNICAMP, Campinas, SP; 3 Instituto Butantan, São Paulo, SP; 4 Departamento de Farmacologia, FCM, UNICAMP, Campinas, SP, Brazil.
Snakes of the genus Philodryas are widespread in South America and cause most snakebites by colubrids in this region. In this study, we compared the biochemical and pharmacological activities of venom from Philodryaspatagoniensis and Philodryasolfersii. The esterase and phospholipase A activities of both venoms were similar but were much lower than in Bothrops jararaca and Crotalusdurissus terrificus venoms. In contrast, the proteolytic activity of Philodryas venoms was 3-5 times greater than in the two crotalid venoms. SDS-PAGE showed that the Philodryas venoms had similar electrophoretic profiles, with most proteins having a molecular mass of 30-80 kDa. Both Philodryas venoms cross-reacted with bothropic and crotalic antivenoms in immunoblots and ELISA, indicating that they contained proteins immunologically related to Bothrops and C. d. terrificus venoms. Philodryaspatagoniensis venom (1-40 mg/ml) had no effect on mouse phrenic nerve-diaphragm preparations but caused time-dependent neuromuscular blockade of chick biventer cervicis preparations. This blockade was not reversible by washing. The highest concentration of venom tested (40 mg/ml) significantly reduced (p<0.05) the contractures to exogenous acetylcholine (55 and 110 mM) and K+ (13.4 mM) after 120 min; lower concentrations of venom had no consistent or significant effect on these responses. Venom caused a concentration- and time-dependent release of creatine kinase (CK) from biventer cervicis preparations. Histological analysis showed muscle contracture at low venom concentrations and myonecrotic lesions at high concentrations. These results indicate that the venoms of P. olfersii and P. patagoniensis have a similar biochemical, immunological and pharmacological composition.
Correspondence to: lpsantos2000@yahoo.com.br or jccogo@univap.br