[Prevention and treatment of isoproterenol induced ventricular fibrillation in rats by aqueous extract of Salvia miltiorrhiza].

Acute fatal ventricular fibrillation (VF) in male Sprague-Dawley rats was induced by subcutaneous injection of isoproterenol (1 mg or 5 mg/kg body weight) to two groups of rats of different body weights (525 +/- 21 g or 387 +/- 11 g) respectively. VF occurred in all control rats resulting in 96% death with only 4% spontaneously reverted and survived. Pretreatment of animals, with or without pentobarbital anaesthesia, with an aqueous extract of Salvia miltiorrhiza (SM-H, i.p., 5 g herb/kg body weight) significantly reduced J-point displacement and VF induced by isoproterenol. Survival rate was significantly raised compared with the control (P less than 0.05). Immediate intravenous injection of SM-H (5 g herb/kg body weight) to poisoned rats which developed VF caused 71% of them to recover temporarily their sinus rhythm and significantly prolonged their survival time (P less than 0.05).