电针对复杂区域疼痛综合征Ⅰ型大鼠模型痛觉敏化及脊髓胶质细胞活化的影响

Study the intervention of electro-acupuncture on pain sensitization and spinal glial cell activation in rat model of complex regional pain syndrome type Ⅰ

目的:观察电针"足三里""昆仑"穴对复杂区域疼痛综合征Ⅰ型(CRPSⅠ)大鼠模型机械性刺激足反应阈值(MPWT)和热刺激缩足反应潜伏期(TPWL)及脊髓背角星形胶质细胞、小胶质细胞活化的干预作用。方法:SD大鼠40只,随机分为假模型组、CRPSⅠ模型组(模型组)、2/100Hz电针治疗组(电针组)、假电针治疗组,每组10只。模型组采用O型橡胶圈下肢近脚踝处加压模型。电针组取双侧"足三里""昆仑"穴进行干预,1d/次,共14d。检测各组大鼠造模前、造模后1、3、5、7、10、14d患侧MPWT和TPWL。采用免疫荧光法分别检测患侧L4～6段脊髓背角星形胶质细胞和小胶质细胞活化。结果:①电针组大鼠MPWT和TPWL均高于模型组和假电针组(P<0.01)。②与模型组比较,电针组脊髓背角星形胶质细胞活化标记物GFAP和小角质细胞活化标记物OX42表达均显著降低(P<0.05)。结论:电针治疗可有效抑制CRPSⅠ大鼠模型表现的痛觉敏化,促使MPWT、TPWL升高,其镇痛机制可能与显著下调脊髓中的星形胶质细胞和小胶质细胞过度活化有关。

Objective:To observe the effects of electro-acupuncture(EA)on mechanical paw-withdrawal threshold(MPWT)and thermal paw-withdrawal latency(TPWL)in rats with complex regional pain syndrome typeⅠ(CRPSⅠ)by administered at bilateral acupoints Zusanli(ST36)and Kunlun(BL60),and interventional effects of activation of astrocytes and microglia in spinal dorsal horn.Methods:Forty SD rats were randomly divided into sham model group,CRPSⅠmodel group(model group),2/100 Hz EA group(EA group),and a sham EA group,10 in each group.The model group used the O-ring rubber ring lower limb peripheral compression model.In the EA group,Zusanli(ST36)and Kunlun(BL60)acupoints on both sides were taken for intervention once a day for 14 days.The MPWT and TPWL of the affected foot were detected before and after the modeling of the rats in each group at 1 day,3 day,5 day,7 day,10 day,14 day after modeling.Immunofluorescence was used to detect the activation of astrocytes and microglia in the spinal dorsal horn of the L4-6 segment.Results:①MPWT and TPWL in the EA group were higher than those in the sham EA group(P<0.01).②Compared with the model group,the expression of astrocyte activation marker GFAP and small keratinocyte activation marker OX42 in the EA group were significantly decreased(P<0.05).Conclusion:EA could effectively inhibit the pain sensitization of CRPS1 rat model and promote the elevation of MPWT and TPWL.The analgesic mechanism may be related to the significant down-regulation of astrocytes and micro gliaover activation in the spinal cord.