Caracterização bioquímica de duas fosfolipases de lachesis muta muta

Toxicon 46 (2005) 222–229 www.elsevier.com/locate/toxicon

Neurotoxic and myotoxic actions from Lachesis muta muta (surucucu) whole venom on the mouse and chick nerve–muscle preparations
´ Daniela C.S. Damicoa, Lilian G.F. Buenoc, Lea Rodrigues-Simionic, ´ ´ rgio Marangonia, Maria Alice da Cruz-Hoflingb,*, Jose Camillo Novelloa ¨ Se a ´ Departamento de Bioquimica, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), P. O. Box 6109, Campinas, SP, Brazil b Departamento de Histologia e Embriologia, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), P. O. Box 6109, Campinas, SP, Brazil c ˆ ´ Departamento de Farmacologia, Faculdade de Ciencias Medicas, Universidade Estadual de Campinas (UNICAMP), CEP 13083-970, Campinas, SP, Brazil Received 3 September 2004; accepted 8 April 2005 Available online 20 June 2005

Abstract Lachesis genus is one of the less studied among others from Viperidae’s genera, mainly due to difficulties in obtaining the venom. Accidents by Lachesis snakes cause severe envenoming syndrome, eventually leading victims to shock. This work is part of a comprehensive study aimed at studying the venom and its effects. Herein the neurotoxicity and myotoxicity of L. muta muta venom were investigated on mouse phrenic nerve-diaphragm (PNDp) and chick biventer cervicis (BCp) preparations. For both preparations the time required to venom produces 50% neuromuscular blockade was indirectly concentration-dependent, being for PNDp: 117.6G6.5 min (20 mg/ml), 70.1G8.6 min (50 mg/ml) and 43.6G3.8 min (100 mg/ml), and for BCp: 28G 1.8 min (50 mg/ml), 30.4G2.3 min (10 mg/ml), 50.4G4.3 min (5 mg/ml) and 75.2G0.7 min (2 mg/ml), (nZ5/dose). In BCp, a venom dose of 50 mg/ml significantly reduced contractures elicited by exogenous acetylcholine (55 mM) and KCl (20 mM), as well as increased the release of creatine kinase (442.7G39.8 IU/l in controls vs 4322.6G395.2 IU/l, after 120 min of venom incubation (P!0.05). Quantification of