Aim:To explore whether bone marrow mesenchymal stem cells(MSC)can differ-entiate into myocardial-like cells induced by myocardial medium,especially thehypoxia/reoxygenation-conditioned medium of cardiomyocytes.Methods:Myo-cardial cells obtained from neonatal Sprague-Dawley rat ventricles were isolatedand cultured in vitro and a hypoxia reoxygenation model was established.TheMSC isolated from adult Sprague-Dawley rats were purified and then incubatedwith 3 different mediums:medium A-the conditioned medium of normalcardiomyocytes;medium B-the conditioned medium of cardiomyocytes afterhypoxia reoxygenation;and the control medium-ordinary medium.The expres-sions of the cardiac myosin heavy chain(MHC),troponin T(TnT)and connexin43 were investigated in the MSC after 24 h,48 h and 72 h cultivation,respectively.Results:The MSC expressed MHC and TnT when incubated with the condi-tioned medium of cardiomyocytes after hypoxia reoxygenation,but did not ex-press connexin 43.None ofMHC,TnT and connexin 43 was detected in the MSCincubated with the conditioned medium of normal cardiomyocytes.Conclusion:The results indicate for the first time that myocardial medium for hypoxic precon-ditioning can induce MSC differentiation into myocardial-like cells. Aim: To explore whether bone marrow mesenchymal stem cells (MSC) can differ-entiate into myocardial-like cells induced by myocardial medium, especially the hypypia / reoxygenation-conditioned medium of cardiomyocytes. Methods: Myo-cardial cells obtained from neonatal Sprague-Dawley rat ventricles were isolated and cultured in vitro and a hypoxia reoxygenation model was established. The MSC was purified from the conditioned medium of cardiomyocytes ; and the control medium-ordinary medium. The expres-sions of the cardiac myosin heavy chain (MHC), troponin T (TnT) and connexin43 were investigated in the MSC after 24 h, 48 h and 72 h cultivation, respectively. Results: The MSC expressed MHC and TnT when incubated with the condiedized medium of cardiomyocytes after hypoxia reoxygenation, but did not ex-press connexin 43. Not of MHC, TnT and conne xin 43 was detected in the MSCincubated with the conditioned medium of normal cardiomyocytes. Conclusion: The results indicate for the first time that the myocardial medium for hypoxic precon-ditioning can induce MSC differentiation into myocardial-like cells.