Abstract: Objective To observe the effect of TSA to induce mesenchymal stem cells(MSCs) differentiating into cardiomyocyte cells, to explore the effective conditions． Methods MSCs were incubated in different concentration of TSA and different duration time, then detected the histone deacetylase(HDAC) activity; the differentiation of MSCs was observed by phase-contrast mictmcopy;fluorescence immunohistochemistry assessed cardiac troponin T and RT-PCR detected the expression of Nkx-2.5、GATA-4 genes．Result The HDAC activity was the lowest when incubated with 300nmol/L TSA for 24 hours, expression of cTnT of the cells was enhanced after incubated with TSA. The expression levels of Nkx-2.5、GATA-4 genes were enhanced before interference.Conclusion TSA can advance MSCs to differentiate into cardiomyocyte cells in vitro in a suitable condition.

Key words: histone deacetylase inhibitors, mesenchymal stem cells, diferentiation, cadiocyte