Abstract: Objective: To investigate the antiarrhythmic effects on neonatal rat cardiac myocytes of extracts from the mycelia of Cephalosporium sinensis. Methods: The model arrhythmia of neonatal rat cardiac myocytes induced by CaCl2 and and isoprenaliner espectively in vitro, the antiarrhythmic effects of verapamil, propranolol, fractions of the extracts from the mycelia of Cephalosporium sinensis and the solvent of fractions were tested respectively. Results: EtOH extracts from the mycelia of Cephalosporium sinensis. (Cs-E), the fraction of Cs-E partitioned by EtOAc(Cs-E-Et), and the fraction of Cs-E partitioned by n-BuOH(Cs-E-Bu) had the antiarrhythmic effects on neonatal rat cardiac myocytes induced by the CaCl2 and isoprenaline respectively in vitro. Conclusion: EtOH extracts from the mycelia of Cephalosporium sinensis. (Cs-E), the fraction of Cs-E partitioned by EtOAc(Cs-E-Et), and the fraction of Cs-E partitioned by n-BuOH(Cs-E-Bu) were the bioactive fractions in fermented Mycelia of Cephalosporium sinensis (Ningxinbao).

Key words: Mycelia of Cephalosporium sinensis, neonatal rat cardiac myocytes, arrhythmia