The Role Of The Endogenous Cannabinoid System In The Myocardial Protection Of Electroacupuncture At Ischemia Instantly

ObjectiveIt has been reported that electroacupuncture (EA) pretreatment could reducemyocardial peroxidation and myocardial apoptosis, and improve myocardialischemia-reperfusion injury. Endocannabinoids (eCB) also activate a series of downstreamsignal transduction pathways through its receptors CB1and CB2, and play an importantrole in myocardial ischemia-reperfusion injury. To further explore the mechanism of EAtreatment on myocardial ischemia-reperfusion, the aim of this experiment is to investigatethe protective effects of EA at ischemia instantly on myocardial ischemia-reperfusioninjury, and the effects of EA on eCB. MethodsEighty adult male SD rats were randomly divided into8groups (n=10): controlgroup (I/RI group), I/RI+EA group, I/RI+AEA group, I/RI+2-AG group, I/RI+AM251group, I/RI+AM630group, I/RI+EA+AM251group and the I/RI+EA+AM630group. AEA (10mg/kg),2-AG (5mg/kg), AM251(1mg/kg) and AM630(1mg/kg)was intraperitoneal injection30minutes before myocardial ischemia. A "Neiguan" electricneedle stimulation (rate2/100HZ，strength4mA) was given at the same time of ischemiafor30minutes. After an ischemia for30minutes and reperfusion for2hours, the blood ofrats was collected to detect myocardial enzymes, the brain was taken for TTC staining andTUNEL staining.Results1. Compared with the control group (I/RI group), EA stimulation significantly reduced thevolume of myocardial infarction and myocardial apoptosis after ischemia-reperfusion,while decreased the cTnI and CK in blood.2. Compared with the control group (I/RI group), AEA and2-AG also significantlyreduced the volume of myocardial infarction and myocardial apoptosis afterischemia-reperfusion, while decreased the cTnI and CK in blood.3. Compared with the control group (I/RI group), AM251and AM630significantlyincreased the volume of myocardial infarction and myocardial apoptosis afterischemia-reperfusion, while rised the cTnI and CK in blood. In addition, themyocardial protection of EA was blocked by AM251or AM630.Conclusion1. EA stimulation at ischemia instantly plays an important protective role on myocardialischemia-reperfusion injury.2. The myocardial protective effects of EA stimulation at ischemia instantly were relatedwith Endogenous cannabinoid system.