Efeitos cardiotóxicos do veneno total e da proteína dermonecrótica recombinante da aranha Loxosceles intermedia

Detalhes bibliográficos
Ano de defesa: 2009
Autor(a) principal: Camila Dias Lopes
Orientador(a): Não Informado pela instituição
Banca de defesa: Não Informado pela instituição
Tipo de documento: Dissertação
Tipo de acesso: Acesso aberto
Idioma: por
Instituição de defesa: Universidade Federal de Minas Gerais
UFMG
Programa de Pós-Graduação: Não Informado pela instituição
Departamento: Não Informado pela instituição
País: Não Informado pela instituição
Palavras-chave em Português:
Link de acesso: http://hdl.handle.net/1843/BUBD-928G8X
Resumo: Loxosceles spider bites cause numerous accidents in humans worldwide. In Brasil, loxoscelism brown spider envenomation constitutes the third cause of accidents by venomous animals. Injections of the whole Loxosceles intermedia venom or of recombinant toxin derivated of it (rLiD1) produce in animal models skin-tissue changes and systemic symptoms similar to those detected in humans. The aim of our work was to characterize de cardiac effects induced in mice by L. intermedia venom and rLiD1. L. intermedia antigens were detected in the kidney, heart, lung and liver of experimental envenomed mice by ELISA. Since serum creatine kinase and creatine kinase MB isoenzyme activities were elevated in treated mice, a cardiac action of the venom was further investigated. The binding of rLiD1 to cardiomyocytes was demonstrated by means of an immunofluorescence technique using confocal microscopy. Isolated Langendorff-perfused heart preparations from envenomed mice presented an impairment of the in vitro heart functions. Ventricular cardiomyocites isolated from envenomed mice showed a significant increase of L-type calcium current density and intracellular Ca2+ transients. Taken together, our findings establish the cardiotoxic effects of Loxosceles intermedia spider venom. A protein from sphingomyelinase family plays a key role in the heart mice dysfunction, as attested by cardiac activity of the recombinant toxin rLiD1.