OBJECTIVETo investigate the protective effect of luteolin on isolated rat heart in hypothermic preservation.

METHODSForty male SD rats were randomly divided into 4 groups (n = 10): control group, luteolin low-dose group (7.5 micromol/L), middle-dose group (15 micromol/L) and high dose group (30 micromol/L). Langendorff model of isolated rat heart was used. After 30 min basal perfusion, the hearts were stored in University of Wisconsin solution (UW solution) at 4 degrees C with luteolin (7.5, 15 and 30 micromol/L) or without luteolin for 12 h and followed by 60 min reperfusion. The recovery of cardiac contractile and diastolic function, coronary flow (CF), creatine kinase (CK) leakage in the coronary effluent, myocardial water content were determined. The myocardial ultrastructure was also observed.

RESULTSThe results revealed that luteolin improved the recovery of left ventricular peak systolic pressure and +/- dp/dtmax dose-dependently and increased coronary flow. The leakage of creatine kinase in the coronary effluent was significantly reduced in luteolin-added hearts. Impairment of myocardial ultrastructure after 12 h hypothermic preservation was obviously alleviated in hearts luteolin-added group compared with that in control group. There were no differences between the groups in myocardial water contents.

CONCLUSIONLuteolin as a supplementation in cardiac preservation solution can significantly improve the hypothermic preservation effects on rat heart and have myocardial protection effect, especially in luteolin-added with 30 micromol/L.