补体抑制剂对大鼠神经病理性疼痛模型的作用研究

目的:观察补体抑制剂对神经病理性疼痛(NPP)发病的影响,并初步探讨其机制.方法:18只SD大鼠随机分成三组:A组:假手术+术后生理盐水静脉注射;B组:慢性坐骨神经结扎模型(CCI)+术后生理盐水静脉注射;C组:CCI模型+术后眼镜蛇毒因子(CVF)静脉注射.大鼠致伤模型建立后第一天开始根据分组每日尾静脉注射CVF 50μg/kg或等量的生理盐水.分别于术前和术后1、3、5、7天测定大鼠的热痛阈值和机械痛阈值,并于术后7天处死大鼠取腰6、7脊髓节段,测定SOD和MDA的组织含量.结果:CCI模型大鼠术后第1天均出现痛阈下降,给于补体抑制剂CVF干预后大鼠痛阈逐渐恢复而生理盐水对痛阈无影响;与A组相比,B组大鼠术后第7天脊髓SOD活力明显降低而MDA显著升高;C组SOD和MDA变化幅度显著小于B组.结论:CVF显著改善了CCI模型大鼠痛敏状态,可能的机制是CVF维护了脊髓氧化一抗氧化平衡,从而呈现出对脊髓组织的保护作用.

EFFECTS OF COMPLEMENTS INHIBITOR ON THE NEUROPATHIC PAIN MODEL IN RATS

Objective:To observe the effects of complements inhibitor on the neuropathic pain(NPP)rats and discuss its mechanisms.Methods:Eighteen Sprague-Dawley rats were divided randomly into 3 groups as following:Rats in Group A were operated shamly with normal saline intravenous injection postopera- tion,those in Group B received chronic sciatic constriction injury(CCI)and normal saline intravenous injection postoperation,rats in Group C received CCI and cobra venom factors(CVF)intravenous injec- tion at 50μg/kg postoperation.Pain threshold by thermal or mechanical stimulation was recorded at pre- operation and the 1 st,3rd,5th,7th day after operation in each rat.The levels of superoxide dismutase (SOD)and malondialdehyde(MDA)in the related segments of spinal cord were detected at the 7th day after operation with eolorimetric method.Results:Pain threshold of paw withdraw decreased at the 1 st day postoperation in all CCI rats.The decreased threshold recovered gradually following the injection of complements inhibitor(CVF)but remain constant when rats received the administration of normal saline. Compared with the rats in Group A,those in Group B showed significant decrease in SOD activity and in- crease in MDA level in spine tissues.The change magnitude of SOD and MDA in Group C was obviously less than those in Group B.Conclusions:The sensitivity of pain was alleviated by intravenous CVF injec- tion in the CCI models of rats,and the mechanisms might be that CVF improved the balanee of oxidation- antioxidation in the CCI related spinal tissues.The results suggest that complements inhibitor could pro- tect the spinal cord from damage.