The neuromuscular activity of Micrurus pyrrhocryptus venom and its neutralization by commercial and specific coral snake antivenoms

• Autores: Camargo, Thiago Magalhães; de Roodt, Adolfo R.; da Cruz-Höfling, Maria Alice; Rodrigues-Simioni, Léa
• Año de publicación: 2011
• Idioma: inglés
• Tipo de recurso: artículo
• Fuente: Journal of Venom Research 2011; 2: 24-31.
• Materia: Elapidae; Bloqueo Neuromuscular; Proteínas Neurotóxicas de Elápidos
• Institución: Administración Nacional de Laboratorios e Institutos de Salud "Dr. Carlos G. Malbrán"

Fil: Camargo, Thiago Magalhães. University of Campinas. Department of Pharmacology; Brasil.
Fil: de Roodt, Adolfo R. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Producción de Biológicos; Argentina.
Fil: da Cruz-Höfling, Maria Alice. University of Campinas. Department of Histology and Embryology; Brasil.
Fil: Rodrigues-Simioni, Léa. University of Campinas. Department of Pharmacology; Brasil.
The neuromuscular activity ofMicrurus pyrrochryptus venom was studied in chick biventer cervicis (BC) and mouse phrenic nerve-diaphragm (PND) preparations. The venom (0.5-50μg/ml) caused irreversible, time- and concentration-dependent blockade, with BC being more sensitive than PND (50% blockade with 10μg/ml in 22±;3min and 62±4min, respectively; mean±SEM, n=6; p<0.05). In BC preparations, venom (0.5μg/ml) progressively abolished ACh-induced contractures, whereas contractures to exogenous KCl and muscle twitches in curarized preparations were unaffected. The venom neither altered creatine kinase release (venom: 25.8±1.75IU/l vs control: 24.3±2.2IU/l, n=6, after 120min), nor it caused significant muscle damage (50μg of venom/ml vs control: 3.5±0.8% vs 1.1±0.7% for PND; 4.3±1.5% vs 1.2±0.5% for BC, n=5). The venom had low PLA2 activity. Neurotoxicity was effectively neutralized by commercial Micrurus antivenom and specific antivenom. These findings indicate that M. pyrrhocryptus venom acts postsynaptically on nicotinic receptors, with no significant myotoxicity.