Abstract: [Abstract] Objective To investigate the apoptotic effect of microRNA-1(miR-1) on hypoxemic cardiomyocytes. Methods The cultured H9C2cells were divided into5groups: normal control group, negative control group, H2O2group, miR-1group and H2O2+miR-1group. After verified the success of transfection by real time PCR, MTT and flow cytometry methods were used to test the cell vitality and apoptotic rate, while the mRNA and protein expression level of Bcl-2were de? tected by real time PCR and Western blot methods. Results Compared with normal control group, there were no significant differences in all indexes in negative control group. The application of H2O2 and miR-1respectively or together significantly increased the miR-1level and apoptotic rate, and reduced the cell vitality and Bcl-2expression level.Conclusion mi? croRNA-1can induce cardiomyocyte apoptosis by downregulating anti-apoptosis factor Bcl-2.

Key words: hypoxemic, cardiomyocyte, cell apoptosis, microRNA, miR-1