Abstract: Objective To study the effects of propofol on myocardial injury and ROS level induced by H2O2. Methods Cardiac myocytes are treated with H2O2 and propofol，as control group, H2O2 group and 15, 30 and 60 μmol/L propofol group.MTT detection of cell viability, the leakage rate of LDH was detected by two nitrophenyl hydrazine colorimetric assay, cell apoptosis was detected by flow cytometry, Western blot was used to detect the level of cleaved caspase-3 protein in cells and the level of Cytochrome C protein in cytoplasm and mitochondria, SOD activity was detected by xanthine oxidation, CAT activity was detected by ammonium molybdate method, the activity of GSH-Px was detected by two thio two Nitrobenzoic Acid method, thiobarbituric acid method was used to detect the content of MDA, the level of ROS was detected by two chloro two fluorescein acetoacetate method, the JC-1 method was used to detect the mitochondrial membrane potential. Results Compared with control group,the activity of myocardial cells decreased in H2O2 group, the leakage rate of LDH was increased, the rate of apoptosis increased, the level of cleaved caspase-3 protein in the cells increased, SOD activity, CAT activity and GSH-Px activity reduced, the content of MDA in the cells increased and the content of ROS increased, the membrane potential of cell mitochondria decreased, the level of Cytochrome C protein in the cytoplasm increased, the levels of Cytochrome C protein in mitochondria decreased（P<0.05）. Compared with H2O2 group, the activity of cardiomyocytes in propofol group improved, the leakage rate of LDH decrease , the rate of apoptosis and the level of cleaved caspase-3 protein in cells decreased, SOD activity , CAT activity and GSH-Px activity in cells increased, the content of MDA and ROS in cells decreased, mitochondrial mitochondrial membrane potential improved, the Cytochrome C protein level in the cytoplasm reduced, the level of Cytochrome C protein in mitochondria improved（P<0.05）. Conclusions Propofol alleviated the injury of cardiomyocytes induced by H2O2, reduce cell apoptosis and reduce the level of ROS in cells.

Key words: cardiomyocytes, hydrogen peroxide, ROS, apoptosis, Propofol