Reactive Oxygen Species Mediate Cardiac Myocyte Hypertrophy Induced By PGF_2α

Objective: The effects of PGF2αon the reactive oxygen species generation and cardiomy- ocyte hypertrophy were examined in experiments on the cultured neonatal rat cardi omyocytes. It is to study the role of ROS in the signaling pathway of cardiomyocyte hypertrophy induced by PGF2α.Methods: The study was performed with primary cultured neonatal rat cardiac myocytes. Cardiomyocyte hypertrophy was determined by the total protein content of cells and the cell diameter. The level of intracellular ROS was measured by the ROS-specific probe 2′,7′- dichlorofluorescin diacetate (DCF-DA). We divide randomly cardiomyocytes into six groups:contrast,1nmol/lPGF2αgroup,10nmol/lPGF2αgroup,100nmol/lPGF2αgroup,100nmol/l PGF2α+CAT group and 100nmol/l PGF2α+ Egb group. The total protein of cell was measured by the methods of coomassie brilliant blue. The cell diameter was measured by image analysis program. Intracellular fluorescence signal was assayed by fluorescence convert microscope.Results: Cardiac myocytes treated with PGF2α(1nmol/l,10nmol/l,100nmol/l),the fluor- escence intensity of intracellular DCF-DA increased by 38.99%,61.76% and 93.55% respectively (F=195.686,P<0.01)VS control group. It is indicated that PGF2αcan induce intracellular ROS generation on the cultured neonatal rat cardiomyocytes in dose-dependent manners. The total protein content of cells increased by39.51%,69.93% and 139.06% respectively (F=74.014,P<0.01) VS control group; the cell diameter increased by 29.02%,60.79% and 127.40% respectively (F=721.020,P<0.01) VS control group. It is indicated that PGF2αinduce cardiomyocyte hypertrophy on the cultured neonatal rat cardiomyocytes in dose-dependent manners. Compared with Prostaglandin F2α(100nmol/l)group, the fluorescence intensity of intracellular DCF-DA ,the total protein c ontent of cells and the cell diameter decreased by 35.41%(P<0.01),42.42% and 47.70% respectively in Prostaglandin F2α(100nmol/l) group treated with catalase(200U/ ml);The fluorescence intensity of intracellular DCF-DA ,the total protein content of cells and the cell diameter decreased by26.56%(P<0.01), 19.37% and 32.95% respectively in Prostaglandin F2α(100nmol/l) group treated with EGb (40μg/ml)VS Prostaglandin F2α(100nmol/l) group. It is suggest that antioxidants(CAT and EGb) can attenuate intracellular ROS generation and cardiomyocyte hypertrophy by PGF2α.Conclusion: PGF2αcan induce intracellular ROS generation and cardiomyocyte hypertrophy on the cultured neonatal rat cardiomyocytes in dose-dependent manners. Antioxidants can attenuate effectively intracellular ROS generation and cardiomyocyte hypertrophy by PGF2α.