目的 :比较不同经穴电针治疗大鼠慢性神经源性痛的疗效。方法 :选用大鼠L5/L6 脊神经结扎慢性神经源性痛模型

给予不同经穴的电针治疗

穴位选用“夹脊”(L5)、“环跳”、“委中”、“阳陵泉”和“足三里”。采用引起缩足的机械刺激阈值 ( 50 %缩足阈值 )来评价机械性痛觉超敏

用大鼠 5min内在 5± 1℃冷板上的抬脚次数来反映冷诱发的持续性疼痛。分别于电针后即刻、2 4hr、48hr和 72hr检测冷诱发的持续性疼痛 ;电针后即刻、电针后 1 2hr、2 4hr和 48hr检测机械性痛觉超敏 ( 50 %缩足阈值 )

以观察其疗效。结果 :以上五个穴位单次电针均有较好的镇痛作用。对冷诱发的持续性疼痛的抑制均可持续至电针后 2 4hr

其中“委中”对冷诱发的持续性疼痛的抑制作用可持续至电针后 48hr;对机械性痛觉超敏的镇痛作用即刻效果较好

电针后 1 2hr消失。五个穴位镇痛强度之间在统计学上无显著差异。结论 :临床经验提示穴位选择是影响针刺镇痛效果的重要因素之一。在本实验条件下

“委中”穴电针后的镇痛作用持续时间最长

可以认为效果最优Objective: The present study is aimed at comparing the analgesic effects of electroacupuncture (EA) at different acupoints in neuropathic pain rats. Methods: L 5/L 6 nerve was ligated with surgical suture thread (gauge-6) to establish neuropathic pain model (Chung method). SD rats were randomly divided into 5 groups

namely "Jiaji"(EX-B 2)

"Huantiao"(GB 30)

"Weizhong"(BL 40)

"Yanglingquan"(GB 34) and "Zusanli"(ST 36) acupoint groups

with 11 cases being in each group. These acupoints were punctured with acupuncture needles and stimulated electrically with HANS (wave duration 0.6 ms

2 Hz

0.5～2 mA) for 30 min. Mechanical allodynia was assessed by 50% paw withdrawal threshold with von Frey filaments and cold-induced ongoing pain was detected by the number of paw lifts within 5 min when the rat was put on to the 5±1 ℃ cold plate freely. Fifty percent paw withdrawal threshold was assessed immediately following EA

12 hrs and 24 hrs following EA treatment

and cold-induced ongoing pain was also assessed just after EA

24 hrs

48 hrs and 72 hrs following EA treatment. Results: After the EA treatment

all the 5 acupoints had instant analgesic effects on neuropathic pain (P<0.01

0.001) and the analgesic effect could maintain 24 hrs. There was no significant difference among the 5 acupoint groups concerning the long-lasting analgesic effect on 50% paw withdraw threshold and cold-induced ongoing pain. Only "Weizhong"(BL 40) produced longer long-lasting analgesic effect on cold-induced ongoing pain (48 hrs following EA treatment). The immediate effect of EA on mechanical allodynia was better

lasting about 12 hrs. Conclusion: Results of the present study demonstrate that EA treatment has a remarkable analgesic effect

while "Weizhong"(BL 40) seems to be better than the other 4 acupoints under our experimental conditions.