Abstract: Objective To investigate the influence of increasing the proportion of plant oil in the diet on the ω-6 /ω-3 PUFAs ratio of myocardium and the effect of those on the infection status and mitochondrial function in the at risk area after ischemia /reperfusion. Method 80 C57BL/6 mice, randomly divided into ordinary diet group and plant oil group(n=40/group). One month later, myocardial ischemia/reperfusion model was built, mitochondria were isolated by differential centrifugation. Oxygen consumption was determined by oxygen electrode. 2,3,5 triphenyltetrazolium chloride (TTC) staining was used to measure infarction size. real time reverse transcription-polymerase chain reaction(RT-PCR) was used to detect the mRNA expression of TNF-a, amount of TNF-a and IL-1 were measured by ELISA. Results: compared with the ordinary diet group, in the plant oil group, ω-6 /ω-3 PUFAs ratio of myocardium was lower , after ischemia/reperfusion, the mRNA expression of TNF-a, amount of TNF-a and IL-1 in the area at risk was lower , the respiration control rate of myocardium in the area at risk improved apparently and the Infarction size were diminished. Conclusion: unsaturated fatty acids improves the lipid composition of myocardium , improved the mitochondrial function after ischemia/reperfusion in mice.

Key words: polyunsaturated fatty acids, ischemia-reperfusion injury , mitochondria, inflammatory factor