Effects of electroacupuncture of "Shenmen" (HT 7) and "Taixi" (KI 3) on cardiac sympathetic activities in acute myocardial ischemia rabbits

OBJECTIVE: To observe the effect of electroacupuncture (EA) of different acupoints on activities of the cardiac sympathetic nerve in rabbits with acute myocardial schemia (AMI). METHODS: A total of 40 Chinchilla rabbits were randomized into normal control, model, Shenmen (HT 7), Taixi (KI 3) and non-acupoint groups (n8/group). AMI model was established by intravenous injection of pituitrin (3 U/kg). EA (1.1 mA, 2 Hz) was applied to bilateral HT 7, KI 3 and non-acupoint (the bulge site of the triangular muscle) for 10 mm. The rabbit's cardiac sympathetic discharges were recorded by BIOPAC under anesthesia. RESULTS: In comparison with control group, the heart rate (HR) and the frequency of cardiac sympathetic discharges (CSD) decreased significantly after AMI (P < 0.01). At the moment of cease of EA, at 20 mm after EA, HR and 050 frequency in HT 7 group were significantly higher than those of model group (P < 0.01), suggesting a favorable inhibition of EA of HT 7 on the decreased HR and OSO. No significant differences were found between KI 3 and model groups, and between KI 3 and non-acupoint groups in both HR and OSD at any time courses (P > 0.05). CONCLUSION: EA of HT 7 can correct AMI-induced decrease of both HR and OSO in the rabbit, while EA of KI 3 and non-acupoint have not this effect, suggesting a relatively specific efficacy of EA of different acupoints on cardiac sympathetic activities.