天麻素对小鼠炎性痛脊髓背角自发放电抑制作用  

Gastrodin inhibits spontaneous firing in spinal dorsal horn neurons induced by inflammatory pain

作　　者：肖梅梅 胡三觉[2] 董辉[1] 罗层[2] 

机构地区：[1]第四军医大学西京医院麻醉科,西安710032 [2]第四军医大学基础部神经科学研究所,西安710032

出　　处：《神经解剖学杂志》2015年第2期149-154,共6页Chinese Journal of Neuroanatomy

基　　金：国家自然科学基金(31171065;31471059);国家973计划(2014CB543200);陕西省重点科技创新团队(2012 KCT-14)

摘　　要：目的：探究天麻素（gastrodin or GAS）对炎性痛小鼠诱致的脊髓背角I层神经元自发放电的影响。方法：成年小鼠10只,一侧后足底皮下注射完全弗氏佐剂（complete Freund’s adjuvant,CFA）制备炎性痛模型后,于6、12、24、48、96、168 h分别观察机械性缩足反射阈值（paw withdrawal mechanical threshold,PWMT）和热刺激缩足反射潜伏期（paw withdrawal thermal latency,PWTL）的变化。选取出生14~18 d小鼠,按照上述相同方法建立炎性痛模型,24 h后制备脊髓薄片（300μm）,孵育1 h后用全细胞膜片钳技术通过灌流系统给予GAS（300μmol/L）,并探究其对炎性痛脊髓背角I层神经元自发放电的影响。结果：（1）在成年小鼠炎性痛模型中,CFA诱致的痛觉过敏可持续1~2周,在24 h达到高峰;（2）在出生14~18 d小鼠CFA注射24 h后,脊髓背角I层神经元出现显著的自发放电增强现象;（3）GAS可以显著抑制脊髓背角I层神经元自发放电的频率,对幅度无显著作用。结论：GAS对炎症导致的脊髓背角I层神经元自发放电增强具有显著的抑制作用,进而降低神经元的兴奋性,从而达到缓解炎性痛的效果。Objective： To explore the effect of gastrodin（ GAS） on spontaneous firing in spinal dorsal horn lamina I neurons induced by inflammatory pain. Methods： The 10 adult mice were set up inflammatory pain model induced by unilateral injection of Complete Freund’s Adjuvant（ CFA） into the plantar surface of hindpaws. The change of paw withdrawal mechanical threshold（ PWMT） and paw withdrawal thermal latency（ PWTL） were observed on hour 6,12,24,48,96 and 168 h,respectively. The postnatal 14-18 d mice were set up inflammatory pain model according to the above same method. The spinal cord slices（ 300 μm） were prepared on 24 h after inflammatory pain model. Whole-cell patchclamp recording was used by perfusion system to investigate the effect of GAS（ 300 μmol / L） on spontaneous firing in spinal cord lamina I neurons induced by CFA inflammation after 1 h incubation. Results：（ 1） Intraplantar injection of CFA induced a dramatic mechanical and thermal hyperalgesia which lasts for 1-2 weeks,reaching the peak at 24 h after injection in adult mice.（ 2） Frequent spontaneous firing was observed in a population of spinal dorsal horn lamina I neurons at24 h after CFA-induced inflammation in the postnatal 14-18 d mice.（ 3） GAS markedly inhibited the frequency of thespontaneous firing in spinal cord lamina I neurons after CFA inflammation. Conclusion： GAS can dramatically inhibit the spontaneous firing in spinal cord lamina I neurons induced by inflammatory pain,which results in the reduction of the excitability of neurons and alleviation of inflammatory pain.

关 键 词：天麻素 脊髓背角I层神经元 自发放电 CFA炎性痛 小鼠 

分 类 号：R285.5[医药卫生—中药学]