Abstract:

Objective To investigate the protection of ghrelin against doxorubicin ⁃induced heart failure and cardiac injury in rats and underlying mechanisms. Methods A total of 32 Sprague ⁃Dawley（SD）rats were randomized into control group，heart failure group and ghrelin group. Rat heart failure was induced by intraperitoneal injection of doxorubicin. The rats with heart failure in the ghrelin group and those in the heart failure and control groups were intraperitoneally injected with ghrelin and the same volume of saline twice per day，respectively. The changes in echocardiographic parameters，cardiac hemodynamics，myocardial histology，plasma levels of TNF⁃α， IL⁃10 and 15⁃F2t⁃isoprostane in the rats were analyzed. Results Compared with the heart failure group，the rats in the ghrelin group had significantly lower LVSD（P < 0.05），higher left ventricular ejection fraction（LVEF） （P < 0.05）and maximum rise speed of left ventricular pressure（+dP/dtmax）（P < 0.01）. Histological analysis revealed that the rats in the ghrelin group had lesser cardiomyocyte degeneration and necrosis than those in the heart failure group. Mechanistically，the rats in the ghrelin group had significantly lower plasma levels of TNF ⁃ α and 15⁃f2t ⁃isoprostane（P < 0.01），but higher plasma IL ⁃10 level（P < 0.05）. Conclusion Ghrelin improves cardiac function of doxorubicin⁃induced heart failure and ameliorates myocardial injury at least in part through regu⁃ 

Key words: