OBJECTIVETo study the protection effects and the mechanisms of Huoxue Anxin Recipe (HAR) on acute myocardial infarction (AMI) rats.

METHODSThe AMI Wistar rat model was prepared by ligating the left anterior descending coronary artery. By taking elantan long as the positive control drug, HAR was extracted from Chinese herbs by modern pharmacological methods and composed according to theories of Chinese medicine (CM). The medication time started from the day of modeling to the 21st day of the modeling. The heart function, the morphological changes of the heart, changes in the mRNA and protein levels of toll like receptor 4 nuclear factor kappa B tumor necrosis factor alpha (TLR4-NFkappaB-TNFalpha) pathway were observed.

RESULTSCompared with the sham-operation group, the ejection fraction (EF) and left ventricular fractional shortening (FS) significantly decreased (P < 0.01), the left ventricular intemal dimension end-diastolic (LVIDd) and left ventricular internal dimension end-systolic (LVIDs) significantly increased (P < 0.01), the mRNA and protein levels of TLR4-NFkappaB-TNFalpha channel significantly increased in the model group (P < 0.01). The infarction in the front wall of the left ventricle was obviously seen, accompanied with severe inflammatory cell infiltration and collagen deposition in model group. Compared with the model group, the EF and FS significantly increased, LVIDd and LVIDs significantly decreased in the positive control group, the high and low dose HAR groups (P < 0.05, P < 0.01). The infracted area of the front wall of the left ventricle was obviously contracted. The inflammatory cell infiltration and collagen deposition were obviously alleviated. In the high and low dose HAR groups, the mRNA and protein expression levels of TLR4-NFkappaB-TNFalpha significantly decreased (P < 0.05, P < 0.01), but no inhibition was found in the positive control group.

CONCLUSIONSHAR could significantly improve the morphological structures and functional abnormality induced by myocardial ischemia in AMI rats. Its effects was correlated with inhibiting TLR4-NFkappaB-TNFalpha pathway.