AIM To investigate the direct cardioprotective effects of ghrelin on ischemic/reperfusion injury of isolated hearts in rats.
METHODS Using the ischemic/reperfusion (I/R) model of rat hearts, the effects of ghrelin on hemodynamics of
isolated rat hearts were observed, and the ghrelin receptor binding sites in sarcoplasm membrane of ischemic and I/R hearts were also tested. RESULTS Ghrelin obviously improved the disturbance of hemodynamics and metabolism of I/R injury in isolated rat hearts,which showed as increased cardiac contraction ability, decreased LDH, Mb leakage out from rat hearts, and decreased myocardiac MDA generation and increased ATP content. The receptor binding site test showed that the ghrelin receptor binding sites were increased in ischemic and I/R injury hearts in rats, whereas the affinity of ghrelin to ghrelin receptor in heart sarcoplasm membrane has no obviously change. CONCLUSIONS Ghrelin exerts directly
protective effects on ischemic/reperfusion injury of isolated heart in rats in a growth hormone-independent manner.