| 摘要: | 神經痛是一種盛行率高的慢性疼痛，目前臨床上缺乏有效治療，藥物治療也常伴隨副作用。針灸治療被廣泛應用於鎮痛，可藉誘發endorphin釋放緩解疼痛，且電針可產生較手針更佳的療效。目前對於電針治療神經痛的療效及機轉並不十分清楚，因此本研究以4-0鉻腸線在Sprague-Dawley大鼠右側坐骨神經做寬鬆結紮，以建立神經痛動物模式，並以2 Hz電針治療委中（BL40）、承山（BL57）穴，探討其效用及機轉。24隻大鼠隨機分為4組，每組6隻，包括：1)正常組（normal group, NG）不接受神經結紮及電針（electro-acupuncture, EA）；2)偽電針組（sham EA group, SG）接受偽電針及神經結紮；3)同側電針組（ipsilateral EA group, IEAG）接受同側電針及神經結紮；4)對側電針組（contralateral EA group, CEAG）接受對側電針及神經結紮。術後每日觀察大鼠行為表現，並測量右後肢抬起次數及輻射熱痛刺激試驗之潛伏期，比較左右兩側潛伏期差值（difference score）。術後第15天將大鼠犧牲取腦，以西方點墨法分析大腦皮質Par1區域之transient receptor potential vanilloid type 1（TRPV1）濃度。結果顯示，不論同側或對側 2 Hz電針治療委中、承山穴，皆可減少大鼠鉻腸線誘發神經痛之右後肢抬起次數，並增加潛伏期之difference score，但Par1區域之TRPV1濃度則無顯著變化。由於同側或對側2 Hz電針治療可緩解大鼠因鉻腸線誘發之神經痛，推測2 Hz電針或可應用於人類神經痛治療，而電針治療神經痛與TRPV1間之關聯則有待更深入探討。
Neuropathic pain is a chronic pain with high prevalence and few effective therapies. Although acupuncture stimulation can induce endorphin release and has been widely applied for pain control, there is still little known about the effect of acupuncture on neuropathic pain. Electro-acupuncture (EA) can produce greater effect than manual acupuncture has been known. Therefore, the purpose of the present study was to investigate effect and mechanisms of EA on neuropathic pain. We used a 4-0 chromic gut with 4 loose ligatures around the right sciatic nerve proximal to trifurcation in Sprague-Dawley (SD) to establish a neuropathic pain animal model. A total of 24 rats were study, they were divided into 4 groups of 6 rats as follow: 1) Normal Group (NG), without any ligation and EA; 2) sham EA group (SG), sham EA applied to right BL40 and BL57 acupoints; 3) Ipsilateral EA Group (IEAG), 2 Hz EA applied to right BL40 and BL57 acupoints; 4) Contralateral EA group (CEAG), 2Hz EA applied to left BL40 and BL57 acupoins. The behavior was observed, the counts of lifting right hind limb was counted, and radiant heat test was performed daily from first day to 15th days after operation. The level of transient receptor potential vanilloid type 1 (TRPV1) in Par1 area also was measured by western blotting. The results indicated that the counts of lifting hind limb was greater in the SG than in the NG , and the difference score of radiant heat test was smaller in the SG than NG. IEA and CEA treatment can reverse these decreases of the difference score, and reduce the counts of lifting hind limb. Therefore, the level of TRPV1 in Par1 area has no significant difference between them.
EA applied to right or left BL40 and BL57 acupoints could reverse the decrease of the difference score, and reduce the counts of lifting hind limb in rats with CCI. However, TRPV1 of Par1 area may not be related to this effect. EA could relief the neuropathic pain in rats induced by chromic gut, suggesting that EA could potentially have similar effect on neuropathic pain relief on human. As regard to the relationship between EA-treating neuropathic pain and TRPV1 needs further study. |
