ABSTRACT
OBJECTIVE: To observe the effect of electroacupuncture (EA) on ischemic electrocardiogram (ECG), histopathological changes and serum metabolite profile in chronic myocardial ischemia (CMI) rats, so as to reveal its mechanisms underlying protecting ischemic myocardium. METHODS: A total of 45 male Wistar rats were randomly divided into normal control, CMI model and EA groups, with 15 rats being in each group. The rats in the control group received subcutaneous injection of 0.9% normal saline (5 mg•mg－1•d－1, for 7 days), and those in the model and EA groups received subcutaneous injection of isopropylarterenol hydrochloride (5 mg•mg－1•d－1, for 7 days) to establish CMI model. EA (2 Hz/100 Hz, 1 mA) was applied to bilateral "Zusanli" (ST 36), "Guanyuan" (CV 4) and "Neiguan" (PC 6) for 10 min, once daily for 21 days. The ECG-ST segment of the standard limb lead II was used for evaluating the severity of myocardial ischemia, and the histopathological changes of myocardium were observed under microscope after H．E. staining. The profile of serum metabolites was analyzed by nuclear magnetic resonance mass spectrometry combined with principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) in 21 rats (n＝7 in each group)．. RESULTS: After modeling, the amplitude of ECG-ST was significantly increased in comparison with the normal control group (P 1). The PLS-DA analysis revealed deviations in 51 differential biomarkers in serum，among which, Glucose, Lactate, Creatine, Acetate and 3-Hydroybutyrate may contribute to the effect of EA in improving CMI. CONCLUSION: EA stimulation of acupoints can ameliorate ischemic myocardial injury in CMI rats, which may be related to its effect in regulating serum sugar, lipid metabolism and energy metabolism.