摘要
目的:观察鞘内给予雷公藤内酯(triptolide,T10)对于慢性炎性痛和神经病理性痛模型大鼠脊髓背角小胶质细胞内p38丝裂原激活的蛋白激酶(p38 mitogen-activated protein kinase,MAPK)的磷酸化水平的影响。方法:采用大鼠足底注射完全弗式佐剂(complete Freund’s adjuvant,CFA)构建慢性炎性痛模型,L5脊神经结扎(spinal nerve ligation,SNL)和坐骨神经分支选择性结扎(spared nerve injury,SNI)的方法制作慢性神经病理性痛模型。利用von Frey丝刺激法连续观察造模后大鼠的痛行为变化;应用免疫荧光染色方法观察大鼠腰膨大节段胶质纤维酸性蛋白(glial fibrillary acidic protein,GFAP)和电离钙绑定衔接分子1(ionized calcium binding adaptor molecule-1,Iba-1)的表达水平;应用Western Blot方法观察大鼠腰膨大节段p38 MAPK的磷酸化水平。结果:(1)行为学结果显示:CFA、SNL、SNI模型大鼠机械性痛阈均明显降低,且术后一周内与正常对照组相比均保持在较低水平(P<0.01)。从术后第1 d起鞘内连续给予T10至第7 d,分别观察到T10能够明显提高上述模型大鼠手术侧后足的机械性痛阈(P<0.05);但T10在SNL模型和SNI模型大鼠中的效果要弱于CFA引起的慢性炎性痛(P<0.05)。(2)免疫荧光染色结果显示:CFA、SNL和SNI模型大鼠腰膨大脊髓背角内GFAP、Iba-1的表达明显高于正常对照组,而p-p38 MAPK阳性产物主要表达于小胶质细胞内。(3)Western Blot结果显示:造模后7 d脊髓背角内p-p38 MAPK的表达明显上调,鞘内给予T10后可以显著下调脊髓背角内p38的磷酸化水平(P<0.05)。结论:鞘内给予T10有效缓解由于CFA、SNL和SNI诱导的慢性痛模型大鼠的机械性痛阈的机制可能是通过下调脊髓背角内p38 MAPK信号通路的磷酸化水平,进而达到抑制小胶质细胞和星形胶质细胞的活化。其次,T10对不同类型的疼痛模型的作用效果存在差异,对由CFA引起的慢性炎性痛的作用效果要强于由SNL和SNI诱导�
Objective： To observe the effects of intrathecal injection of triptolide （T10） on chronic inflammatory pain and neuropathic pain induced the phosphorylation level of p38 mitogen-activated protein kinase （MAPK） in the spinal dorsal horn microglial. Methods ： The chronic inflammatory pain was set up by intraplanter injection of complete Freund ＇s adjuvant （CFA）; the chronic neuropathic pain was built by L5 spinal nerve ligation （SNL） and spare nerve injury （SNI） respectively. The von Frey filament was used to investigate the mechanical allodynia after different chronic pain models of rats. Immunofluorescent histochemistry was applied to analyze the expression level of glial fibrillary acidic protein （GFAP） and ionized calcium binding adaptor molecule-I （ Iba-I ） -like immunoreactivites. Western Blot was applied to qualitatively analyze the phosphorylation level of p38 MAPK in the spinal dorsal horn of lumbar segment. Results： （ 1 ） The behavioral results showed that the hindpaw withdrawal mechanical threshold in CFA-induced chronic inflammatory, SNL and SNI-induced neuropathic pain model rats were obviously decreased, and were stayed at lower levels in one week after operation compared with control group （P 〈 0. 01）. The hindpaw withdrawal mechanical threshold in the above toodais rats were observed respectively to increase after intrathecal injection of T10 from post operations day 1 to day 7 （P 〈 0.05 ） ; but the effect of TIO on CFA pain model rats was better than SNL and SNI（P 〈 0.05）. （2） Immunofluorescent histochemical staining results showed that the expression level of GFAP and Iba-1 in the dorsal horn of lumbar spinal cord were significantly up-regulated after CFA, SNL and SNI administration; And p-p38 was expressed mainly in spinal cord microglial. （3） Western Blot results indicated that the expression of p-p38 MAPK was higher than normal group （P 〈 0.05） after pain models building, and intrathecal T10 could down-regulate the phosphor
出处
《神经解剖学杂志》
CAS
CSCD
北大核心
2016年第1期18-24,共7页
Chinese Journal of Neuroanatomy
基金
国家自然科学基金(81571074)
