摘要
目的 :已知电针能减轻大鼠辐射热引起的疼痛和急、慢性炎症痛 ,本文探讨电针能否减轻大鼠神经源性痛。方法 :将大鼠右侧L5/L6 脊神经结扎 ,用引起 5 0 %缩足的机械刺激阈值评价机械性痛觉超敏 ,用大鼠 5min内在 5± 1℃冷板上的缩足次数反映冷诱发的持续性疼痛。用韩氏穴位神经刺激仪给予电刺激 ,波宽 0 .6ms ,频率 2Hz ,电流强度为 0 .5 ,1和 2mA ,各 10min ,共刺激 30min。结果 :2Hz电针能减轻痛觉超敏 (持续 1h)和冷诱发的持续性疼痛 (持续 12小时 )。电针前15min皮下注射纳洛酮 (1mg/kg)能阻断电针对冷诱发的持续性疼痛的作用 ,但不能阻断对痛觉超敏的作用。结论 :低频 (2Hz)电针可能通过阿片机制减轻持续性的神经源性疼痛 ,低频电针也能减轻机械性痛觉超敏 ,该作用可能不是通过阿片机制完成的。
Objective:Our previous studies showed that electroacupuncture(EA) inhibited radiant heat induced pain and acute or chronic inflammatory pain in rats. We now study whether EA could suppress neuropathic pain. Methods: L 5/L 6 nerve ligation model was used to assess the effect of EA on neuropathic pain. Mechanical allodynia was represented by 50% paw withdrawal threshold and cold-induced ongoing pain was detected by the number of paw lifts in 5 min when the rat was put on a 5±1℃ cold plate. Han's acupoint nerve stimulator (HANS) was connected to needles inserted into acupoints 'Jiaji'and 'Zusanli' on both sides.The parameters were: 0.5-1-2 mA intensity, 10 min each; 2Hz frequency, 0.6 ms in pulse width. Results: (1) EA could relieve the mechanical allodynia and cold-induced ongoing pain, the relieving effect on mechanical allodynia outlasted the EA session by up to about 1 h, the latter persisted longer, at least 12 h after EA. (2) naloxone (1 mg/kg s.c., injected 15 min prior to EA) blocked the analgesic effect of EA on cold-induced ongoing pain, but not on mechanical allodynia. Conclusion: 2 Hz EA could relieve both cold-induced ongoing pain and mechanical allodynia, via opioid and non-opioid mechanisms respectively.
出处
《中国疼痛医学杂志》
CAS
CSCD
2003年第4期220-224,共5页
Chinese Journal of Pain Medicine
