Neuromuscular activity of Bothrops fonsecai snake venom in vertebrate preparations

Journal of Venom Research

 José C¹  Rita CO¹  Vânia MA¹  Léa¹  Ana M¹  Edvana O¹  Igor RF da¹  Carla T¹  Stephen¹  Luiz S¹ 

关键词: Bothrops fonsecai;    myotoxicity;    neuromuscular blockade;    neurotransmission;    post-synaptic;   

DOI  :  

学科分类：药理学

来源: Library Publishing Media

【 摘 要 】

The neuromuscular activity of venom from Bothrops fonsecai, a lancehead endemic to southeastern Brazil, was investigated. Chick biventer cervicis (CBC) and mouse phrenic nerve-diaphragm (PND) preparations were used for myographic recordings and mouse diaphragm muscle was used for membrane resting potential (RP) and miniature end-plate potential (MEPP) recordings. Creatine kinase release and muscle damage were also assessed. In CBC, venom (40, 80 and 160mg/ml) produced concentration- and time-dependent neuromuscular blockade (50% blockade in 85±9 min and 73±8 min with 80 and 160ug/ml, respectively) and attenuated the contractures to 110uM ACh (78-100% inhibition) and 40mM KCl (45-90% inhibition). The venom-induced decrease in twitch-tension in curarized, directly-stimulated preparations was similar to that in indirectly stimulated preparations. Venom (100 and 200ug/ml) also caused blockade in PND preparations (50% blockade in 94±13 min and 49±8 min with 100 and 200ug/ml, respectively) but did not alter the RP or MEPP amplitude. In CBC, venom caused creatine kinase release and myonecrosis. The venom-induced decrease in twitch-tension and in the contractures to ACh and K⁺ were abolished by preincubating venom with commercial antivenom. These findings indicate that Bothrops fonsecai venom interferes with neuromuscular transmission essentially through postsynaptic muscle damage that affects responses to ACh and KCl. These actions are effectively prevented by commercial antivenom.

【 授权许可】

Unknown