Intravascular hemolysis induced by Lonomia obliqua caterpillar bristle extract: an experimental model of envenomation in rats

Autor(es)

Seibert, Carla Simone ^[1] ; Oliveira, Mara Regina L. ; Gonçalves, Luís Roberto C. ; Santoro, Marcelo Larami ; Sano-Martins, Ida Sigueko

Afiliação do(s) autor(es)

^[1] São Paulo (Estado). Secretaria de Estado da Saúde. Instituto Butantan. Divisão de Desenvolvimento Científico - Brasil

• Tipo de documento: Artigo Científico
• Fonte: Toxicon; v. 44, n. 7, p. 793-799, dez. 2004.
• Área do conhecimento: Ciências Biológicas - Bioquímica
• Assunto(s): Fisiopatologia Hemólise animal Lonomia obliqua

Resumo

Hemostatic disturbances are frequent findings in human accidents caused by Lonomia obliqua caterpillars in the southern region of Brazil. In severe envenomation, patients may present life-threatening bleedings. Such disturbances may be mimicked in rats, which also develop intravascular hemolysis. The scope of this study was to investigate the time-course and intensity of intravascular hemolysis induced by i.d. injection of 750 µg/kg crude L. obliqua bristle extract in rats. Total blood cell count, reticulocyte count, plasma hemoglobin and haptoglobin assays were performed in control and envenomed rats at 1, 6, 24 and 48 h after envenomation. Rats presented a drastic drop of haptoglobin levels at 1 and 6 h with increased plasma hemoglobin levels, a decrease in packed cell volume values at 6, 24 and 48 h, and increased reticulocyte counts throughout after envenomation. Such observations indicated that intravascular hemolysis occurred as early as 1 h following envenomation, and lasted for more than 6 h. Intravascular hemolysis is probably induced by phospholipase A2 and other proteins with direct hemolytic activity present in crude caterpillar bristle extract. (AU)

• Processo FAPESP: 97/01193-2 - Acidente por contato com cerdas de lagartas lonomia: tratamento do acidente humano e do experimental em ratos; purificacao e caracterizacao bioquimica de componentes ativos.
• Beneficiário: Ida Sigueko Sano Martins
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 98/07144-6 - Ação do extrato de cerdas da lagarta Lonomia obliqua (Walker 1855, Saturniidae) sobre eritrócitos humanos e de ratos
• Beneficiário: Carla Simone Seibert
• Modalidade de apoio: Bolsas no Brasil - Mestrado