Neurotoxic and myotoxic actions from Lachesis muta muta (surucucu) whole venom on the mouse and chick nerve–muscle preparations

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: 117.6±6.5 min (20 μg/ml), 70.1±8.6 min (50 μg/ml) and 43.6±3.8 min (100 μg/ml), and for BCp: 28±1.8 min (50 μg/ml), 30.4±2.3 min (10 μg/ml), 50.4±4.3 min (5 μg/ml) and 75.2±0.7 min (2 μg/ml), ( n=5/dose). In BCp, a venom dose of 50 μg/ml significantly reduced contractures elicited by exogenous acetylcholine (55 μM) and KCl (20 mM), as well as increased the release of creatine kinase (442.7±39.8 IU/l in controls vs 4322.6±395.2 IU/l, after 120 min of venom incubation ( P