RESUMO
OBJECTIVE: To explore the improvement effect and the regulating mechanism of electroacupuncture with "Shuanggu Yitong" prescription methods on learning memory and immunosenescence in aging rats with yang deficiency. METHODS: Forty female Sprague-Dawley rats, 5-month-old, were randomly divided into a normal control (NC) group, an aging yang deficiency model (M) group, an electroacupuncture with Shuanggu Yitong prescription methods (EA) group and an electroacupuncture control (EAC) group, 10 rats in each group. The aging model rats with yang deficiency were established by hypodermic injection of D-galactose for 40 days and then intramuscular injection of Hydrocortisone for 7 days in the latter three groups except the NC group The EA group was treated with electroacupuncture at "Guanyuan" (CV 4), "Housanli" (ST 36) and "Baihui" (GV 20), and the EAC group was treated with electroacupuncture at "Zhongji" (CV 3), "Yinlingquan" (SP 9) and "Yintang" (EX-HN 3), six times per week for 4 weeks. The escape latency was examined by Morris water maze from the first day of the 4th week. After completion of electroacupuncture treatment, the rate of spleen lymphocyte apoptosis and the serum content of tumor necrosis factor-a (TNF-alpha) were examined by flow cytometry and enzyme linked immunosorbent assay (ELISA) technique respectively, the differences among all the groups above were compared. RESULTS: In comparison with the NC group, the escape latency [(25.4 +/- 3. 6)s vs. (16.23 +/- 2.3)s], the rate of spleen lymphocyte apoptosis [(27.25 +/- 3.3)% vs. (13.2 +/- 3.1)%] and the serum content of TNF-alpha [(15.54 +/- 3.56) pg/mL vs (7.35 +/- 2.89) pg/mL] in the M group those were all significantly increased (all P < 0.01). In the EA group, the escape latency of (17.42 +/- 3.9)s, the rate of spleen lymphocyte apoptosis of (17.2 +/- 3.25)% and the serum content of TNF-alpha of (9.51 +/- 3.53) pg/mL were all significantly lower than those in the M group (all P < 0.01) and the EAC group (all P < 0.05). CONCLUSION: Electroacupuncture with "Shuanggu Yitong" prescription can significantly improve the spatial learning and memory. The protective mechanism is related with the action of electroacupuncture in lowering the rate of spleen lymphocyte apoptosis and the serum content of TNF-alpha, and the therapeutic effect of electroacupuncture at "Guanyuan" (CV 4), "Housanli" (ST 36) and "Baihui" (GV 20) is superior to that of electroacupuncture at "Zhongji" (CV 3), "Yinlingquan" (SP 9) and "Yintang" (EX-HN 3).