摘要
目的观察大鼠坐骨神经慢性压迫性损伤(CCI)后脊髓背角P物质表达的变化,探讨P物质在疼痛发生机制中的作用。方法SD雄性大鼠60只,随机分为:A组:CCI组(30只);B组:对照组(30只)。术前及术后3、7、14、28 d分别测定大鼠热痛阈值、机械痛阈值和行为学评分。术后3、7、14、28d每组取4只,麻醉后用4%多聚甲醛灌注固定,取L4-6段脊髓,以备免疫组化,测定SP的变化。结果所有CCI动物从术后第3天起,出现明显的疼痛行为学改变和热痛阈值、机械痛阈值的降低,与对照组比较差异有统计学意义(P<0.05或P<0.01)。免疫组织化学结果表明,A组术后术侧明显高于B组(P<0.05或P<0.01);A组术侧明显高于健侧(P<0.05或P<0.01);而B组仅在第4天术侧高于健侧(P<0.05)。结论慢性坐骨神经损伤后,脊髓背角SP的表达增加,而且表达增加与CCI大鼠的痛觉过敏、行为变化在时相上基本一致,说明CCI大鼠痛觉过敏与脊髓背角SP的表达增加有关。
Objective To observe the expressive variety of substance P in the dorsal horn of spinal cord on neuropathic pain by chronic constriction injury（CCI）. Methods Sixty male Sprague-Dawley rats were randomly divided into two groups：CCI group, control group. Record the responsiveness to mechanical and thermal stimuli before and after sciatic nerve constriction injury. Immuno-histochemistry technique was used to measure the expression of substance P in the dorsal horn of spinal cord at 3th,7th,14th,28th days following sciatic nerve constriction injury. Results The rats＇ responsiveness to mechanical and thermal stimuli and pain behavior were significantly increased on postoperative days after sciatic nerve ligation compared with preoperative（ P 〈 0. 05 ）. The relative expression level of substance P was obviously increased at 3 day in the dorsal horn of spinal cord after sciatic nerve constriction injury compared with preoperative （P 〈 0. 05）. In group A increase in substance P expression in the dorsal horn of spinal cord was obviously increased compared with groupB （ P 〈 0. 05 ）. Conclusions The CCI rats＇ sensitivity to thermal and mechanical stimuli was significantly increased following sciatic nerve constriction injury. This could be related to the increase of substance P expression in the dorsal horn of spinal cord.
出处
《中国实用医药》
2008年第34期5-7,共3页
China Practical Medicine
基金
湖北省科技厅自然科学基金项目(项目编号:2005ABA080)
郧阳医学院优秀中青年科技创新团队计划(项目编号:2005CXX04)
