电针穴位刺激对锂-匹罗卡品诱导致痫大鼠行为及脑电活动的影响

Effect of electroacupuncture stimulation at acupoint on behavior and electroencephalogram of rats with epilepsy induced by lithium-pilocarpine

目的:观察电针刺激百会穴对锂-匹罗卡品诱导致痫大鼠的行为及脑电活动的影响,进一步揭示穴位刺激的抑痫机制。方法:实验于2005-06在解放军第四军医大学西京医院神经内科完成。①选用成年雄性SD大鼠30只。利用脑立体定位手段,将电极埋入大鼠脑部双侧额叶皮质、海马和杏仁核。②选取24只大鼠,脑内植入电极1周后,予大鼠腹腔注射锂-匹罗卡品,造成强直-阵挛性发作癫痫持续状态模型。③将癫痫发作程度(依据Ono等分级标准)Ⅳ级(含Ⅳ级)以上存活大鼠18只随机分为3组:电针穴位刺激组(电针刺激致痫大鼠百会穴),电针刺激对照组(电针刺激致痫大鼠百会穴相临的非穴位处),无刺激对照组(造模后不给予其他干预措施),每组6只。均采用G-6805型电针治疗仪于致痫后第2天开始进行电针刺激干预,共刺激3周。电针刺激参数为:频率为80Hz,电流强度20mA,时间20min,2次/d。其余6只大鼠为正常对照组:取脑内植入电极,但未致痫大鼠,腹腔注射与匹罗卡品等量生理盐水。④记录致痫大鼠首次癫痫发作平均潜伏期、注射地西泮前强直-阵挛发作次数和持续时间,以及静默期的长短。此后,每天观察动物的行为学变化4h,记录其静默期后出现的Ono等分级标准Ⅰ～Ⅲ级的自发反复发作次数。⑤采用太阳公司视频脑电描记系统记录脑电。右海马-右耳连续描记各组大鼠致痫前15min到注射地西泮终止发作期间的脑电变化,以及致痫后在第2,3,4,6周时大鼠的脑电图改变(时间2h)。⑥计量资料差异比较采用方差分析。结果:造模后存活18只及正常大鼠6只进入结果分析。①各组致痫大鼠首次癫痫发作平均潜伏期、注射地西泮前强直-阵挛发作次数和平均持续时间比较,差异不明显(P>0.05)。电针穴位刺激组大鼠平均每周自发反复发作次数明显少于电针刺激对照组和无刺激对照组大鼠(P<0.05)。②正常大鼠脑电波形频率以5～10Hz为主,波幅小于200μV。注射后经过潜伏期,大鼠脑电图表现出多种形式的癫痫样波,有单棘波,多棘波,多相棘波,棘慢波,发作性节律波等。频率最快可达35Hz,波幅高约2.5～3.0mV,发作后可出现抑痫制波。电针穴位刺激组大鼠在第2,3,4,6周时脑区杏仁核内2h内放电次数明显少于电针刺激对照组和无刺激对照组(P<0.05)。结论:电针刺激百会穴对锂-匹罗卡品诱导致痫大鼠的慢性发作具有明显的抑痫作用,其电生理机制依赖于抑痫信号的穴位-神经传入解剖途径。

AIM： To investigate effect of electroacupuncture stimulated at Baihui acupoint on behavior and electroencephalogram of rats with epilepsy induced by lithium-pilocarpine and reveal anti-epilepsy mechanism of acupoint stimulation further. METHODSi The experiment was completed at the Neurological Department of Xijing Hospital Affiliated to the Fourth Military Medical University of Chinese PLA in June 2005. ① Totally 30 adult male SD rats were selected, The stereotaxic technique was used to implant accurately the electrodes into bilateral frontal cortex, hippocampus and amygdala nucleus of brain. ② After one week, 24 rats were injected with lithium-pilocarpine intravenously to induce stiff-clonus status epilepticus model. ③ According to level of epilepsy [（One equal classification） Ⅳ grade （including Ⅳ grade）], 18 survival rats were randomly divided into three groups： acnpoint group （eleetroacupuncture stimulated at Baihui acupoint）, acupoint control group （electroacupuneture stimulated near to Baihui acupoint）, and nonstimulation control group with 6 in each group. Tbe second day after epilepsy, rats were treated with electroacupuncture by G-6805 electroacupuncture therapeutic meter for 3 weeks. Parametes of electroacupuncture： frequency was 80 Hz, intensity of current was 20 mA, and time was 20 minutes for twice a day. Another 6 rats were regarded as normal control group. Electrodes were transplanted into brain of rats, and the rats were injected with saline of the same volume of pilocarpine intravenously. ④ Average latency, times and lasting time of stiff-elonic onset before injection of diazepam and length of become-silent period by the first time of epileptic seizure were recorded. Then, behaviors were observed for 4 hour everyday so as to record spontaneous and repeat times of epileptic seizure at grade Ⅰ-Ⅲ of One equal classification. ⑤ Electroencelphalograms were recorded with Video Eleetroencelphalogram Tracing System （Sun Company）, changes of electroencelphalogram of fight＇ hippoeampus and right ear were recorded from 15 minutes before epilepsy to stopping onset induced by diazepam, and changes of eleetroencelphalogram in the 2^nd, 3^rd, 4^th and 6^th weeks were recorded for 2 hours respectively. ⑥ Measured data were cmnpared with analysis of variance. RESULTS： Totally 18 survival rats and 6 normal rats entered the final analysis. ① Comparisons between average latency and times and lasting time of stiff-elonic onset before injection of diazeparo by the first time were not significantly different （P 〉 0.05）. Spontaneous and repeat times of epileptic seizure in acupoint group were less than those in acupoint control group and non-stimulation control group （P 〈 0,05）. ② Frequency of brain wave of normal rats was 5-10 Hz and amplitude of wave was less than 200 μV. After injection, electrueneelphalogl;am showed many kinds of epileptic wave, such as single spike wave, muhiple spike wave, polyphas spike wave, spike-slow wave, attack-rhythm wave, etc. The fastest frequency was 35 Hz and height of amplitude was 2.5-3.0 inV. Anti-epilepsy wave was ohsevced after onset. Times of. discharge in nucleus amygdalae of rats within 2 hours in acupoint group were less than those in acupoint control group and nonstimulation control group in the 2^nd, 3^rd, 4^th and 6^th weeks （P 〈 0.05）. CONCLUSION： Electroaeupuncture stimulated at Baihui acupoint can efficiently inhibit the chronic onset of epileptic rats induced by lithiumpiloca^rpine, and the mechanisms of electrophysiology rely on the anatomy route of acupoint-nerves introduce.