| 摘要: | 神經病變性疼痛是一種不易治療的慢性疼痛，而電針已廣泛地使用於對疼痛的治療。因此，本研究的目的即是探討2Hz低頻電針對於神經病變性疼痛的療效和機轉。我們將鉻線寬鬆結紮Sprague-Dawley（SD）大鼠的右側坐骨神經以建立一個chronic constrictive injury（CCI）誘發神經病變性疼痛的動物模式。實驗一，觀察CCI誘發神經病變性疼痛的行為與電針的療效，動物行為於術前及術後第1~10天進行。18隻SD大鼠隨機分為3組。(1)正常組：在大鼠左和右腳均切開表皮層和肌肉層並暴露坐骨神經，但不結紮坐骨神經。(2)控制組：在大鼠右腳以鉻腸線寬鬆結紮坐骨神經，而左腳只切開表皮層和肌肉層並暴露坐骨神經，但沒有使用鉻腸線寬鬆結紮坐骨神經。沒有施予電針刺激。(3)電針組：手術方法同控制組，但在術後第1~3天，以及第7~9天在氣體麻醉下分別在右側環跳穴和陽陵泉穴施予2Hz電針20 min，並於每日電針前施行輻射熱試驗；實驗二，觀察電針的療效與機轉，動物行為於術前及術後第7~9天電針前及電針後90 min施行。32隻SD大鼠隨機分為4組。(1)正常組：在大鼠左和右腳均切開表皮層和肌肉層並暴露坐骨神經，但不結紮坐骨神經。(2)控制組：在大鼠右腳以鉻腸線寬鬆結紮坐骨神經，而左腳只切開表皮層和肌肉層並暴露坐骨神經，但沒有使用鉻腸線寬鬆結紮坐骨神經。沒有施予電針刺激。(3)假電針組：手術方法同控制組，但於術後第7~9天，大鼠在氣體麻醉下分別用不銹鋼針灸針刺入右側環跳穴、陽陵泉穴，並留針20 min，但不捻針也不通電刺激。(4)電針組：手術方法同控制組，但於術後第7~9天在氣體麻醉下分別在右側環跳穴和陽陵泉穴施予2Hz電針20 min。大鼠於術後第9天觀察行為完成後犧牲，並取出第4到第6腰椎背根神經節，利用西方點墨法測定Glial cell line-derived neurotrophin factor（GDNF）、GDNF family receptor α-1 (GFRα-1)及Ret濃度。結果：實驗一）術前正常組和控制組兩者之右─左後肢腳底輻射熱試驗的潛伏期差相似（p > 0.05）；電針組於電針刺激後隔日電針前的右─左後肢腳底輻熱試驗的潛伏期差小於控制組（p < 0.05），但術後第5～7天的右─左後腳足底輻射熱試驗的潛伏期差則電針組和控制組相似（p > 0.05）；實驗二）電針後90 min，以及隔日電針前的右─左後肢腳底輻射熱試驗的潛伏期差都是控制組大於電針組（p < 0.05）。術後第9天右側第4到第6腰椎背根神經節中GDNF、GFRα-1、Ret的濃度均是控制組大於正常組（p < 0.05）；而2Hz電針於施予右環跳和陽陵泉能減少這些增加（p < 0.05）。鉻線束緊右側坐骨神經誘發神經病變性疼痛，也同時引起同側背根神經節組織之GDNF、GFRα-1和Ret濃度的增加；2Hz電針能減輕神經病變性疼痛，也能減少GDNF、GFRα-1和Ret濃度的增加，電針與同側背根神經節組織之GDNF、GFRα-1和Ret有必要進一步深入研究。
Neuropathic pain is a chronic pain which is resistant to the treatment. Electroacupuncture (EA) has been used widely to treat pain. Therefore, the purpose of the present study was to investigate the effect and mechanisms of 2Hz EA on neuropathic pain. The neuropathic pain animal model was established by using chromic gut loose tie on the right sciatic nerve of Sprague-Dawley (SD) rats. Experiment one, the behavior of neuropathic pain in rat and the therapeutic effect of EA was observed. The behavior of the rat was investigated from first day to 9th day after operation. EA was applied to right Huantiao (GB30) and Yanglingquan (GB34) for 20 min in the first to third day and in the 7th to 9th day, respectively, after operation. The radiant heat test was performed prior to the EA; Experiment two, the effect and mechanisms of 2Hz EA was investigated. EA applied to Huantiao (GB30) and Yanglingquan (GB34) for 20 min, and the radiant heat test was performed before and 90 min after EA, respectively. The rats were sacrificed and the dorsal root ganglions of L4-L6 were take out immediately when finishing the investigation of behavioral in the 9th day after operation.. The concentration of the glial cell-line derived neurotrophin factor (GDNF), GFRa and RET were measured by using western blot method. Results: Experiment one) the radiant heat latency difference of right-left leg (LD) was similar between normal and control group prior to the operation (p > 0.05). The LD was less in the EA group than that in the control group without EA (all p < 0.05).The LD was similar between EA group and control group in the 5th~7th day after operation; Experiment two, The LD was greater in the control group than in the EA group at 90 min after EA and prior to the EA of next day (p < 0.05). The concentration of glial cell-line neurotrophin factor (GDNF), GFRα-1 and Ret of L4-L6 dorsal root ganglion increased in the control group 9th day after CCI-induced neuropathic pain, and theses increased could be reduced by EA treatment (p < 0.05).
Chromic gut lose tie to the sciatic nerve can induced neuropathic pain, and also can increase the concentration of GDNF, GFRα-1 and Ret of dorsal root ganglion. The 2 Hz EA can reduce neuropathic pain and also can reduce the concentration of GDNF, GFRα-1 and Ret. Therefore, there are seemly the relationship between neuropathic pain and GDNF, GFRα-1 and Ret, thus, it is need for further study. EA treats neuropathic pain, this effect of EA cannot maintain longer than 2 days. |
