Introduction: In the present study, the ability of P19 embryonic carcinoma cell differentiation to cardiomyocytes in different concentrations of DMSO was evaluated.
Materials & Methods: In order to providing differentiated P19 cells, embryonic-like objects (Embryoid Bodies, EBs) formed during 2 days through hanging drops method. Then EBs induced for 18 days under the different concentrations of DMSO (0.1%, 0.5%, 1%, 1.5% and 2%). The rate of cardiomyocytes beating was counted with three days interval in the various groups by inverse microscope. Immunocytochemistry was used to illustrate expression of F-actin protein.
 Findings: Many morphological changes occurred in cardiomyocytes derived from P19 especially in DMSO 0.5% group, so a remarkable increase in the size of the cytoplasm and cytoplasmic processes was observed. The results revealed that the maximum beating frequency per minute was observed in DMSO 0.5% group concentration in 2+12 days (2 days for making emberyonic bodies, and 12 days after differentiation induction). In addition, only cardiomyocytes induced differentiation by DMSO 0.5% concentration expressed F-actin which was not expressed in the other concentrations.
 Discussion & Conclusion: The findings of this study suggest that, firstly, the most effective concentration in the process of cardiogenesis induction is 0.5%. Secondly, P19 carcinoma cells are desirable and susceptible to differentiate cardiomyocytes.