辛伐他汀预处理减轻缺血再灌注心肌损伤的实验研究

Objective To investigate the effects of pretreatment with simvastatin on iscbemia reperfusion induced myocardial injury, and to further explore related mechanism with respect to inflammation modulation. Methods The rat myocardial ischemia reperfusion model was established by the method of coronary artery ligation. The animals were divided into 3 groups: the sham group, the control group and the simvastatin group. In the simvastatin group, the animals were pretreated with simvastatin (5 mg/kg) one week before by intragastric administration. Ventricular arrhythmia was monitored and scored, infarct size and area at risk of myocardium were determined, and uhrastructural changes were observed. The serum levels of myocardial enzymes and lipids were measured. The content of myocardial inflammatory cytokines tumor necrosis factor (TNF) -α、interleukin(IL) -6, and monocyte chemoattractant protein(MCP) - 1]were also evaluated. Results When compared with those of the control group, the amount and duration of ventricular arrhythmia in simvastatin group were less and score of ventricular arrhythmia was significantly lower. When pretreated with simvastatin, the serum levels of CK-MB and LDH in simvastatin group were significantly lower than those of the control group. The infarct size/area at risk ratio of the simvastatin treated group was significantly less than those of the control group. The uhrastructures of myocardial cells were better maintained in simvastatin group. No significant differences were observed in the serum concentrations of total cholesterol, triglycerides, low density lipoprotein and high density lipoprotein when comparisons were made each other among the three groups. However, the levels of TNF-α,IL-6 and MCP-1 in heart tissue of the treated animals were significantly lower than those of the control group. Conclusions Pretreatment with simvastatin ameliorates ischemia reperfusion induced myocardial injury, which is partly related with the down-regulation of inflammatory cytokines expression in heart tissue but independent of its role of lipids modulation.

Experimental study on the effects of pretreatment with simvastatin on ischemia reperfusion induced myocardial injury in rats