大鼠坐骨神经慢性挤压性损伤后痛阈和血清IL-6的变化及相关性研究

Changes and relationships of pain threshold and serum IL-6 in rats with sciatic nerve injury induced by chronic constriction

目的:通过大鼠坐骨神经慢性挤压伤(CCI)神经性疼痛模型的热敏变化及血清中IL-6含量的变化,探讨血清IL-6在神经性疼痛形成中的作用及可能机制.方法:36只250～300g的健康雄性Wistar大鼠,在戊巴比妥钠麻醉下于大腿中部暴露坐骨神经并作结扎,取对侧大腿坐骨神经暴露作为模拟对照(B组).术后1,3,5,7,9,11,13,15 d测定大鼠(n=12)两侧后爪对热敏阈值的变化.于术后第15 d处死大鼠,取血清,ELISA法测定IL-6浓度.结果:大鼠双侧后爪(CCI和B)的收缩潜伏期在术后第3,5,7,9,11,13,15 d有显著差异;CCI组血清IL-6与对照组比较有显著差异.结论:IL-6与大鼠坐骨神经慢性挤压性损伤后出现的神经源性疼痛过敏有关.

Objective： To investigate the changes of serum interleukin-6 （IL-6） induced by chronic constriction injury （CCI） of sciatic nerve, and to determine the role of IL-6 in the development of neuropathic pain. Methods ： Thirtysix male healthy Wistar rats weighting 250 to 300 g were anesthetized with sodium barbiturate. Unilateral sciatic nerve was exposed and ligated in the middle of leg in 12 rats in experiment group. Four ligatures were loosely tied around the sciatic nerve, and the distances between the nerve and the ligatures were about 1 mm. The sciatic nerve in the contralateral thigh was exposed and mobilized but not ligated. The thermal nociceptive threshold was determined by measuring the withdrawal latency of hind paw placed on a radiate heat source 3,5, 7, 9, 11 , 13, and 15 days after surgery. The rats were killed 15 days after surgery. Serum was frozen in liquid nitrogen for determining the content of IL-6. The percentage of paw withdrawal latency was determined. Results： The average baseline of nociceptive threshold （withdrawal latency） was （18.25 ± 2.02）s. There was significant difference in paw withdrawal latency between the hind paws 3, 5, 7, 9, 11, 13, and 15 days after surgery. The serum content of IL-6 increased 15 days after surgery. Conclusion： The serum content of IL-6 is ralated to the development of neuropathic pain.