三种频率电针对慢性脑低灌注大鼠rCBF和学习记忆的影响

Effects of Electro-acupuncture at Different Frequencies on rCBF and Learning(Cognitive Function) in Rats with Chronic Cerebral Ischemia

[目的]观察不同频率电针对慢性脑低灌注(Chronic cerebral hypoperfusion,CCH)模型大鼠局部脑血流量(regional cerebral blood flow,r CBF)的影响。[方法]将50只健康雄性SD大鼠随机分为假手术组(Sham)、CCH模型对照组(CCH+Model)、CCH+电针组(CCH+15Hz、CCH+2/50 Hz和CCH+2/100 Hz),每组10只。CCH模型大鼠行双侧颈总动脉结扎,不予任何干预处理;假手术组仅分离双侧颈总动脉。CCH+电针组大鼠是CCH模型给予不同频率电针干预(电针"百会""大椎"),于术后第2天开始行电针干预(1m A,30min,每日1次,连续4周),假手术组和CCH模型组仅同等CCH+电针组抓取固定以平衡处理因素。通过激光多普勒血流仪分别检测大鼠术前、术后即刻、干预后一周、二周及四周时各组大鼠的局部脑血流量,通过Morris水迷宫(Morris water maze,MWM)实验,观察不同频率电针对CCH模型大鼠局部血流和学习记忆(逃避潜伏期)的影响。[结果](1)局部脑血流检测:CCH造模后,各组大鼠r CBF均显示不同程度下降,术后即刻CCH模型组与CCH+电针组差异无统计学意义(P>0.05)。与同时间点假手术组比较,CCH模型组和CCH+电针组各组大鼠的r CBF均显著下降(P<0.01)。与同时间点CCH模型组比较,电针干预后CCH+电针组大鼠r CBF均显著升高(P<0.01)。其中CCH+2/50Hz与CCH+2/100Hz组干预效果最好,优于各时间点CCH+15Hz组。(2)行为学检测:随训练次数的增加,各组大鼠逃避潜伏期呈下降趋势。与同时间点第2、3、4、5天假手术组比较,CCH模型组潜伏期减少缓慢(P<0.01);CCH+电针组潜伏期减少较快(P<0.01或P<0.05)。与同时间点模型组比较,CCH+电针组潜伏期减少较快(P<0.01或P<0.05),其中CCH+2/50Hz和CCH+2/100Hz组平台定位能力优于CCH+15Hz组(P<0.01或P<0.05)。[结论]不同频率电针刺激对CCH模型大鼠具有治疗效应,其机制可能与电针提高CCH模型大鼠的脑血流量进而改善其学习记忆能力有关,其中2/50Hz、2/100 Hz的刺激频率优于15Hz频率。

[Objective] To observe the effects of different frequency electroacupuncture on regional cerebral blood flow（r CBF） in chronic cerebral hypoperfusion（CCH） rats. [Methods] Fifty SD male rats were randomly split into Sham operation group, the CCH model group, CCH＋ electrocardiographic group（CCH ＋15 Hz, CCH ＋2/50 Hz and CCH ＋2/100 Hz）, 10 per group. CCH model rats underwent bilateral common carotid artery ligation. without any intervention; Sham operation group only isolated bilateral common carotid artery. CCH ＋EA group was given CCH model to give different frequency of electro-acupuncture intervention（electroacupuncture points to take ＂Baihui＂, ＂Dazhui＂ two points）, in the second day after the start of electro-acupuncture intervention（1 m A, 30 min, 1 time for 4 weeks）. The Sham operation group and the CCH model group were treated in the same CCH＋EA group to fix the factors. Regional cerebral blood flow was measured by laser Doppler flowmeter in rats before and after operation, one week, two weeks and four weeks after the intervention. Morris water maze（Morris water maze,MWM） was used to observe the effects of different frequencies of electroacupuncture on local blood flow and learning and memory（Escape Latency） in CCH model rats. [Result]1.The levels of r CBF in the CCH model group were much smaller than those in the CCH ＋EA group were not statistically significant（P〈0.05）. The r CBF in the CCH model group and CCH ＋EA group were significantly lower than those in the Sham group（P〈0.01）. Compared with CCH model group, r CBF was significantly increased in CCH＋EA group after electroacupuncture at the same time point（P0.01）. CCH＋2/50 Hz and CCH＋2/100 Hz groups had the best intervention effect, which was better than CCH＋15 Hz group each time point. 2, Behavioral examinations： With the increase in the number of training, the escape latency of rats in each group showed a decreasing trend. At the same time point compared with the Sham group,the latency of the rat at the CCH model group was slowly decreased（ P〈0.01） and the CCH ＋electroacupuncture group was significantly decreased（P0.01）. At the same time point compared with the CCH model group, the latency of the rat at the CCH＋electroacupuncture group was quickly decreased（P0.01 or P〈0.05）. Among the CCH＋electroacupuncture group, the platform positioning capability of the rat at the CCH＋2/50 Hz group and CCH＋2/100 Hz group was better than rat at the CCH＋15 Hz group（ P0.01 or P〈0.05）. [Conclusion] Different frequency electroacupuncture stimulation both has a therapeutic effect on CCH model rats, and its mechanism may be related to the improvement of learning and memory ability of CCH model rats by electroacupuncture, and 2/50 Hz, 2/100 Hz stimulation Frequency is better than 15 Hz.