| Objective To investigate the inhibitory effect of Tanshinone without and with Vacomycin,Oxacillin, Ampicilin,Cephazolin respectively on MRSA in vitro. Methods 20 clinical isolates of MRSA are selected by the Kirby-Bauer method. The MICs of Tanshinone,Vacomycin,Oxacillin, Ampicilin,Cephazolin respectively were detected by the tube dilution,one of the broth dilution in NCCLS. The combined MICs of Tanshinone with Vacomycin ,Oxacillin,Ampicilin,Cephazolin were detected respectively by the dilution.Results There was no statistically significance between the MIC(18.94±8.94μg/ml) of Tanshinone to MRSA and that(14±7.28μg/ml) of Tanshinone to MSSA:ATCC29213.The MIC of Vacomycin,Oxacillin,Ampicilin,Cephazolin is 0.23±0.27μg/ml,198±65.33μg/ml,166.4±60.18μg/ml,153.6±52.53μg/ml respectively when they were used alone.when the four antibiotics were used with Tanshinone,The MIC of Vacomycin,Ampicilin,Cephazolin dropped markedly in vitro(P＜0.01).However the MIC hardly varied when Tanshinone was used with Oxacillin (P>0.05).The average FIC of Tanshinone with Vacomycin was 0.75.The average FIC of Tanshinone with Oxacillin,Ampicilin,Cephazolin is 1.56,1.35,1.31 respectively.CONCLUSION: The growth of MRSA can be inhibited by Tanshinone in vitro.Tanshinone and Vacomycin have synergic effect on MRSA.Tanshinone confers MRSA the increased sensitivity to Vacomycin.The results suggest it is likely that Danshinone be a suppliment of treating patients with MRSA and be used with Vacomycin,it can reduce the latter`s dosage and adverse effect.The results also suggest that Danshinone,a traditional Chinese medicine,is a therapeutic choice in the patients with MRSA infection. |
