Effect of Bothrops leucurus venom in chick biventer cervicis preparations

Bothrops leucurus is a poorly studied pitviper found in northeastern Brazil. We examined the action of B. leucurus venom (5-100 mug/ml) on contractile responses in chick biventer cervicis preparations. Muscle damage was assessed by quantifying the release of creatine kinase (CK) and by histological analysis. B. leucurus venom dose-dependently inhibited the contractile responses of indirectly stimulated preparations, the maximum inhibition with 100 mug of venom/ml being 74.0 +/- 6.6% (mean +/- SEM) after 120 min. The venom also reduced contractures to exogenous acetylcholine (55 and 110 muM) and K+ (13.4 mM) (85-100% reduction with 100 mug of venom/ml) and increased the release of CK (348 +/- 139 U/ml in controls vs 1260 263 U/ml with 20 [mug of venom/ml after 120 min, p < 0.05). The accompanying morphological changes included multivacuolated, swollen, amorphous fibers and agglutinated myofibrils. These results indicate that B. leucurus venom can adversely affect neuromuscular transmission and produce muscle damage in avian preparations. (C) 2003 Elsevier Science Ltd. All rights reserved.41559560