Phoneutria nigriventer spider toxin Tx2-6 causes priapism and death: A histopathological investigation in mice

Autor(es)

Leite, Katia R. M. ^[1] ; Andrade, Enrico ^[1] ; Ramos, Adriana T. ^[2] ; Magnoli, Fabio C. ^[3] ; Srougi, Miguel ^[1] ; Troncone, Lanfranco R. P. ^[2]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Lab Med Invest LIM 55, Dept Urol, Sch Med, BR-01246903 Sao Paulo - Brazil

^[2] Inst Butantan, Pharmacol Lab, BR-05503900 Sao Paulo - Brazil

^[3] Inst Butantan, Lab Immunochem, BR-05503900 Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Toxicon; v. 60, n. 5, p. 797-801, OCT 2012.
• Citações Web of Science: 8

Resumo

Phoneutria nigriventer spider bite causes priapism, an effect attributed to the peptide toxins Tx2-5 and Tx2-6 and involving nitric oxide. Tx2-6 (MW = 5287) is known to delay the inactivation of Sodium channels in the same fashion as many other venom toxins. In the present study we evaluated the i.p. dose that induces priapism and the other symptoms in mice. Animals killed by the toxin or crude venom (0.85 mg/kg) were autopsied and a pathological study of brain, lung, kidney, liver and heart was undertaken using standard techniques. The same protocol was employed with animals injected with crude venom. Results showed that priapism is the first sign of intoxication, followed by piloerection, abundant salivation and tremors. An i.p. injection of about 0.3 mu g/kg induced only priapism with minimal side-effects. The most remarkable histological finding was a general vascular congestion in all organs studied. Penis showed no necrosis or damage. Lungs showed vascular congestion and alveolar hemorrhage. Heart showed also sub-endothelial hemorrhage. Brain showed only a mild edema and vascular congestion. Results obtained with crude venom closely resemble those of purified toxin. We conclude that Tx2-6 have profound effects on the vascular bed especially in lungs and heart, which may be the cause of death. Interestingly brain tissue was less affected and the observed edema may be attributed to respiratory impairment. To the best of our knowledge this is the first histopathological investigation on this toxin and venom suggesting a possible cause of death. (C) 2012 Elsevier Ltd. All rights reserved. (AU)

• Processo FAPESP: 06/57922-3 - Regulacao da expressao genica pela toxina da aranha phoneutria nigriventer no tecido eretil.
• Beneficiário: Miguel Srougi
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 98/02039-0 - Toxinas poliaminicas do veneno da aranha phoneutria nigriventer.
• Beneficiário: Lanfranco Ranieri Paolo Troncone
• Modalidade de apoio: Auxílio à Pesquisa - Regular