G-CSF improves heart function by supression of myocardial remodeling in acute myocardium infarction

AIM To study the effects of Granulocyte colonystimulating factor(G-CSF) on myocardial(remodeling) and cardiac function in acute myocardial infarction(MI).METHODS MI was induced in 40 Japanese big-ear white rabbits by ligating the anterior descending coronary artery.The rabbits were randomly divided into two groups: the vehicle control group receiving saline and the G-CSF group given hypodermic injection of G-CSF 1 h after MI for 7 d.Echocardiography was performed 24 h before MI and 24 h,4 wk after MI.The rabbits were sacrificed at 4 wk and histopathological analysis was made.(RESULTS) The G-CSF group showed better cardiac function than the control at 4 wk.HE staining showed that more orderly orientated myocardial fibers and reduced infarct size in the G-CSF treated group than in the control group.G-CSF treatment also resulted in neogenesis of capillaries and reduced amount of blue collagen fibers as reflected by Masson staining.CONCLUSION The results suggest that G-CSF treatment improves cardiac function by reducing infarct size,increasing neogenesis of capillaries and suppression of myocardial remodelling.