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Protective effect of taurine on cardiotoxicity of the bufadienolides derived from toad (Bufo bufo gargarizans Canto) venom in guinea-pigs in vivo and in vitro.

Jiangsu Key laboratory for TCM formulae research, Nanjing University of Chinese Medicine, Nanjing, China.
Toxicology mechanisms and methods (Impact Factor: 1.37). 01/2012; 22(1):1-8. DOI: 10.3109/15376516.2011.583295
Source: PubMed

ABSTRACT In China, toad venom is an anti-inflammatory agent used in small doses for the treatment of various types of inflammation. Bufadienolides are cardioactive steroids responsible for the anti-inflammatory actions of toad venom. We studied the protective effect of taurine on the cardiotoxicity of bufadienolides in guinea-pigs. Bufadienolides (8 mg/kg) caused arrhythmias, cardiac dysfunction and death in guinea-pigs. Pretreatment with taurine (150, 300 mg/kg) significantly prevented bufadienolide-induced cardiotoxicity and reduced the mortality in vivo. Taurine markedly increased the cumulative doses of bufadienolides and resibufogenin required for lethal arrhythmia in ex vivo isolated guinea-pig heart. Taurine did not compromise the anti-inflammatory activity of the bufadienolides on concanavalin-A-stimulated proliferation of guinea-pig splenocytes in vitro. These data indicate that taurine can prevent bufadienolide-induced cardiotoxicity and could be a novel antidote in combination with bufadienolide therapy.

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