INFLUÊNCIA DA PRESENÇA DE CROTOXINA NA COMPOSIÇÃO DO VENENO DE CROTALUS DURISSUS TERRIFICUS FRENTE AO SORO ANTICROTÁLICO: UMA ABORDAGEM HISTOLÓGICA
DOI:
https://doi.org/10.56238/arev8n3-041Palavras-chave:
Soro Anticrotálico, Crotalus durissus terrificus, Histologia, Preparação Nervo Frênico-Diafragma, Veneno de SerpenteResumo
As principais frações isoladas do veneno de Crotalus durissus terrificus incluem crotamina, girotoxina, crotoxina, convulxina e fosfolipase A2. O soro anticrotálico é produzido a partir de um pool de venenos de Crotalus durissus ssp., que nem sempre expressam crotamina, o que pode refletir na eficácia do tratamento. O objetivo deste estudo foi avaliar, por microscopia de luz, a eficácia do soro anticrotálico nas lesões celulares induzidas pelo veneno de C. d. terrificus com (Vcrot+) e sem (Vcrot−) crotamina. O delineamento experimental foi realizado in vitro, utilizando procedimentos histológicos de rotina em preparações neuromusculares doadas, sob aprovação do Comitê de Ética nº 201/2021, expostas a: 1) controle; 2) Vcrot+; 3) Vcrot−; e tratadas com soro anticrotálico nos modelos de 4) pré-incubação e 5) pós-veneno. Os resultados demonstraram índice de miotoxicidade (IM) nas preparações controle de 42,2 % ± 2,6 células; Vcrot+ 95,2 % ± 1,8; e Vcrot− 89,6 % ± 2,3. No modelo de pré-incubação, o soro anticrotálico reduziu significativamente as lesões para 74,1 % ± 3,8 no Vcrot+ e 71,9 % ± 4,5 no Vcrot−. No modelo pós-veneno, os resultados para Vcrot+ foram: → 10’, 98,0 % ± 0,1; → 30’, 84,8 % ± 0,1; e → 60’, 85,6 % ± 0,1; enquanto para Vcrot− foram 84,7 % ± 0,1; 83,6 % ± 0,01 e 91,9 % ± 0,09, respectivamente. Conclui-se que o soro anticrotálico neutraliza grande parte dos constituintes do veneno no modelo de pré-incubação, enquanto no modelo pós-veneno não foi capaz de neutralizar os efeitos miotóxicos de ambos os venenos, permitindo, contudo, demonstrar a sequência de eventos patológicos em um modelo ex vivo.
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