[Effects of electroacupuncture of different acupoints groups on blood pressure and heart rate variability in rats]

OBJECTIVE: To observe the effect of electroacupuncture (EA) of different acupoint groups on mean arterial pressure (MAP) and heart rate variability (HRV) in hypotension rats. METHODS: A total of 70 Wistar female rats were randomized into model, \"Neiguan\" (PC 6)-\"Daling\" (PC 7), \"Waiguan\" (SJ 4)-\"Yangchi\" (SJ 5), \"Tianshu\" (ST 25)-\"Wailing\" (ST 26), \"Dachangshu\" (BL 25)-\"Qihaishu\" (BL 24), \"Baihui\" (GV 20)-\"Qianshencong\" (EX-HN), and\"Guangming\" (GB 37)-\"Xuanzhong\" (GB 39) groups, with 10 cases in each. Hypotension model was established by bleeding (2.5-3 ml) through carotid artery. Immediately after bleeding, EA (2/15 Hz, 1 mA, 30 min) was applied to the above-mentioned acupoints of the 6 EA groups. MAP and ECG were recorded, then HRV was analyzed by using software Chart 5.2.1. RESULTS: MAP declined significantly after bleeding. Compared with model group, MAP values of PC6-PC7 and GB37-GB39 groups increased significantly 15 min and 30 min after bleeding, and those of ST25-ST26 and GV20-EX-HN groups also increased apparently 30 min after bleeding (P<0.05). No marked effects were observed in EA of SJ4-SJ5 and BL25-BL24 groups (P>0.05). The effect of PC6-PC7 and GB37-GB39 groups was significantly superior to that of SJ4-SJ5, BL25-BL24 and GV20-EX-HN groups in elevating MAP 30 min after bleeding (P<0.05). Compared with model group, heart rate (HR) of PC6-PC7 group was increased significantly 15 min and 30 min after bleeding (P<0.05). After bleeding, low frequency (LF), LF/high frequency (HF) and very low frequency (VLF) increased apparently. Compared with model group, LF, LF/HF and VLF of PC6-PC7 and GB37-GB39 groups decreased significantly 30 min after bleeding (P<0.05), suggesting a better balancing effect of EA of PC6-PC7 and GB37-GB39 on the activities of sympathetic and vagus nerves. CONCLUSION: EA of different acupoint groups has its own relative specificity in regulating MAP and HR in the rat, and PC6-PC7 EA and GB37-GB39 EA have a better efficacy, which is closely associated with their effects in balancing activities of the autonomic nerve system.