RESUMO
AIM: In order to study the relationship of the activation of ERK and delayed cardioprotection of 11,12-EET.METHODS: A rat ischemia/reperfusion(I/R) model was replicated by ligating left anterior descending coronary artery 30 min followed by 60 min.The expression of ERK was detected with Western blotting,and the change of heart function during reperfusion was observed.RESULTS: The difference of myocardial function was prominent at (24 h) in I/R group compared with sham group,EET+I/R and EET+PD098059+I/R group.The activity of ERK at(24 h) in EET+I/R group was higher than sham group, and the activity of ERK in EET+PD098059+I/R group was lower than that in EET+(I/R) group;the expression of phosphorylated ERK1/ERK2 at(24 h) in EET+I/R group was more than that in I/R group,and the expression of phosphorylated ERK1/ERK2 in EET+PD098059+I/R group was less than EET+I/R group.CONCLUSION: 11,12-EET has a delayed cardioprotection effect,and this protection effect is involved in the activity of ERK and expression of phosphorylated ERK1/ERK2.
RESUMO
AIM: To examine the effect of pretreatment with low-concentration of 11, 12-epoxyeicosatrienoic acid(EET) on myocardial ischemia/reperfusion injury in rats. METHODS: After tracheotomy, myocardial ischemia/reperfusion was produced by occlusion and release of the left anterior descending artery(LAD) of the rats. Ischemic preconditioning(IP) was made by two times of ischemia (5 min)/reperfusion (5 min). The experiment was conducted in three groups: control,IP and pretreatment with 11,12-EET(6.24?10 -8 mol/L), and each group was subdivided into two subgroups:A,the rats were subjected to ischemia (10 min)/reperfusion (10 min) and arrhythmias during the whole periods were monitored; The rats in B were subjected to ischemia (60 min)/reperfusion (30 min) and arrhythmias, cardiac funtion and myocardial infarction size were documented. RESULTS: Both IP and pretreatment with 11,12-EET could protect the heart against arrhythmias, cardiac disfunction and myocardial infarction. CONCLUSION: Pretreatment with 11,12-EET had protective effect on myocardium in case of ischemia/reperfusion, which was similar to ischemic preconditioning.