Abstract: Abstract: Objective To investigate the effect of microRNA-1 (miR-1) on H9C2 cardiomyocytes. Methods MiR-1 mimic was transfected into the cultured H9C2 cell line was defined as miR-1 group. Cells transfected with random miRNA fragement was negative control group. Normal control cells had no treatment. The MTT and flow cytometry method were used to test cell vitality and apoptosis rate,while the mRNA and protein expression level of Bcl-2 were detected by real time PCR and western blot methods. Results Compared with the normal control group, negative control cells had no changes. The application of miR-1 mimic can significantly increase the miR-1 level and apoptosis rate, reduce cell vitality and Bcl-2 expression level. Conclusion miR-1 mimic can up-regulate miR-1 level, inhbit proliferation and induce cardiomyocyte apoptosis .

Key words: cardiomyocyte, cell apoptosis, microRNA, microRNA-1 (miR-1)