电针结合银杏酮酯对记忆障碍大鼠学习记忆及海马细胞因子的影响

摘要

目的:研究电针结合银杏酮酯(GBE 50)对D-半乳糖致衰老大鼠学习记忆障碍和海马细胞因子含量的影响,探索针药结合治疗对学习记忆改善作用的机制.方法:SD大鼠随机分成正常对照组、模型组、电针组、银杏酮酯组和针药结合组.采用腹腔注射D-半乳糖的方法建立记忆障碍衰老大鼠模型.电针组在造模第21天开始给予电针治疗,选用"百会"、双侧"足三里"穴位,隔天1次,治疗21 d;银杏酮酯组在造模第21天开始按150 mg/kg给予GBE 50灌胃,每天1次,持续21 d;针药结合组在给予D-半乳糖腹腔注射和GBE 50灌胃后给予电针治疗.治疗结束后采用Morris水迷宫观察大鼠行为学变化以及放射免疫分析方法检测各组大鼠海马白介素(IL)-1β、IL-6和肿瘤坏死因子(TNF)-α的含量.结果:模型组与正常对照组相比逃避潜伏期明显延长,游泳距离百分比明显减少(P＜0.05,P＜0.01);而电针组、银杏酮酯组和针药结合组与模型组相比,逃避潜伏期均显著缩短(P＜0.05,P＜0.01),游泳距离百分比明显增大(P＜0.01),且针药结合组逃避潜伏期与电针组和银杏酮酯组相比差异有统计学意义(P＜0.05).模型组与正常对照组相比大鼠海马IL-1β和TNF-α含量增高,IL-6含量明显降低(P＜0.05,P＜0.01);与模型组比较,电针组、银杏酮酯组、针药结合组大鼠海马IL-β含量均明显降低(P＜0.05,P＜0.01),银杏酮酯组和针药结合组IL-6含量均显著升高(P＜0.01),电针组和针药结合组TNF-α含量明显下降(P＜0.05).结论:电针和GBE 50对大鼠海马IL-1β、IL-6和TNF-α含量均有不同程度的调节作用,抑制D-半乳糖引发的中枢神经系统免疫炎性反应;针药合用在改善学习记忆方面有一定的协同作用.%Objective To observe the effect of electroacupuncture (EA) combined with Ginkgo biloba extract (GBE 50) on learning-memory ability and hippocampal cytokine contents in aging rats for exploring its underlying mechanism in the treatment of dysmnesy. Methods Forty-five SD rats were randomly divided into control (n = 9), model (n = 8), EA (n = 10), GBE 50 (n = 9) and EA + GBE 50 (n = 9) groups. The dysmnesy model was established by D-galactose intraperitoneal injection for 42 days. EA (3 Hz, 1 mA) was applied to "Baihui" (GV 20) and "Zusanli" (ST 36) for 20 min, once every other day for 21 days. The learning-memory ability was detected by Morris water maze tests. The levels of IL-1β, IL-6 and TNF-a in hippocampus were examined by radioimmunoassay. Results Compared with control group, the mean escape latency (MEL) of the rats in model group was significantly greater on the 2~(nd) and 3~(rd) day training (P<0. 05, P<0. 01), and the percent of swimming distance (PSD) in the target quadrant was shortened significantly (P<0. 01). Compared with model group, the MEL values of the rats in EA, GBE 50 and EA + GBE 50 groups were significantly shortened (P<0. 05, P<0. 01), and the PSD values of the later 3 groups increased considerably (P<0. 01). Comparison among the EA, GBE 50 and EA+GBE 50 groups showed that the MEL of EA + GBE 50 was obviously shorter than those of EA and GBE 50 groups (P<0. 05). Compared with control group, the contents of IL-1β and TNF-a in hippocampus in model group increased significantly, but IL-6 decreased markedly (P<0. 05, P<0. 01). In comparison with model group, the IL-1β contents of EA, GBE 50 and EA+GBE 50 groups, and TNF-a of EA and EA+GBE 50 groups were reduced significantly (P<0. 05, P<0. 01); and the contents of IL-6 in GBE 50 and EA + GBE 50 groups increased apparently (P<0. 01). No significant differences were found between model and EA groups in IL-6 levels, and between model and EA + GBE 50 groups in hippocampal TNF-oc levels (P>0. 05). Conclusion Both EA and GBE 50 can improve the dysmnesy rats' learning-memory ability, which may be closely associated with their effects in regulating hippocampal IL-1β, IL-6 and TNF-oc levels to relieve the inflammatory reaction. Combined administration of EA and GBE 50 has a synergic effect.