[Effect of Electroacupuncture Stimulation of Heart Meridian on Autonomic Nervous Activities in Acute Myocardial Ischemia Rats].Zhen Ci Yan Jiu. 2016 Dec 25; 41(6):515-20.ZC
To observe the effect of electroacupuncture (EA) stimulation of the Heart Meridian on electrical activities of neck sympathetic and vagal nerves in acute myocardial ischemia (AMI) rats.
Thirty SD rats were randomly divided into 3 groups, sham operation (sham), model and EA(n=10 rats in each group). The left anterior descending branch (LADB) of the coronary artery was occluded to make an acute myocardial ischemia (AMI) model.For rats of the sham group, a surgical suture was simply threaded beneath the LADB without ligation. EA stimulation (2 Hz, 1 mA)was applied to bilateral "Shenmen" (HT 7), "Tongli" (HT 5) and the middle-point between HT 7 and HT 5 for 20 min. The electrical activities of the left cervical sympathetic and vagal nerves were recorded using a bipolar platinum wire electrodes and a BIOPAC MPl 50 system, and the electrocardiogram (ECG) of the standard limb lead Ⅱ was recorded simultaneously. The AMI severity was evaluated by using J-spot height of ECG.
After AMI, the heart rate (HR), J-spot of ECG, and the discharge frequency of the cervical sympathetic nerve were significantly increased in the model group compared with the sham group (P<0.01), while the discharge frequency of vagal nerve was obviously decreased (P<0.01). Following EA stimulation, the increased levels of HR, J-spot height and discharge frequency of sympathetic nerve, and the decreased discharge frequency of vagus were significantly suppressed at time-points of 1, 3, 5 and 15 min after EA (P<0.01). In addition, the ratio of discharge frequencies of vagal/sympathetic nerves was notably down-regulated after AMI (P<0.01). After EA stimulation, the ratios of vagal/sympathetic discharge at the time-points of 1, 3, 5 and 15 min following EA were significantly increased (P<0.01).
EA stimulation of the Heart Meridian may improve AMI by inhibiting sympathetic discharges and elevating vagal discharges in AMI rats, i.e., coordinating activities of the autonomic nerve systems.