基于降低TLR9表达的电针联合疼痛贴对骨癌痛大鼠的镇痛作用研究

Study on analgesic effect of electroacupuncture combined with Pain Sticker on rats with bone cancer pain based on reduction of TLR9 expression

目的研究电针联合疼痛贴对骨癌痛大鼠的镇痛作用及对脊髓Toll样受体9(TLR9)表达的影响。方法选用雄性SPF级SD大鼠84只,建立大鼠胫骨癌痛模型。将大鼠分为7组,每组12只:模型组、针刺安慰组、胶布安慰组、联合安慰组、电针组、疼痛贴组、联合组。另有空白组大鼠12只。造模成功后给予对应干预12d,进行自发性疼痛评分测定、热痛觉过敏测定、机械性痛觉超敏测定。处死动物,留取腰椎膨大部位冻存,PCR和Western blot检测TLR9的表达。结果空白组的自发性疼痛评分结果低于模型组、缩爪潜伏期(PWL)时间、机械性痛阈值高于模型组(P<0.01)。疼痛贴组、联合组的自发性疼痛评分结果低于模型组、PWL时间高于模型组(P<0.05)。电针组、疼痛贴组、联合组的机械性痛阈值高于模型组(P<0.01)。模型组大鼠脊髓内的TLR9mRNA与蛋白水平明显升高,电针组、疼痛贴组、联合组的TLR9mRNA与蛋白表达水平较模型组均明显下降(P<0.01)。结论疼痛贴联合电针治疗具有缓解骨癌痛大鼠疼痛的作用,其机制与降低TLR9表达有关。

Objective To observe the analgesic effect of electroacupuncture combined with Pain Sticker on the rats with bone cancer pain and its influence on the expression of spinal cord Toll-like receptor 9(TLR9).Methods Eighty-four male SPF SD rats were used to establish the rat tibial cancer pain model.These rats were divided into 7 groups,12 in each group:the model group,acupuncture placebo group,adhesive tape placebo group,combined placebo group,electroacupuncture group,Pain Sticker group and combined group.Other 12 rats served as the blank control.After successfully constructing the model,the corresponding intervention was given for 12 d.The spontaneous pain score,thermal hyperalgesia and mechanical pain hypersensitivity were measured.The animals were sacrificed and the bulge parts of the lumbar vertebra were cryopreserved;the expression of TLR9 was detected by PCR and western blot.Results The spontaneous pain score in the blank group was lower than that in the model group,the paw withdrawal latency(PWL)time and mechanical pain threshold value were higher than those in the model group(P<0.01).The spontaneous pain score in the Pain Sticker group and combined group was lower than that in the model group,while their PWL time was higher than that in the model group(P<0.05).The mechanical pain threshold value in the electroacupuncture group,Pain Sticker group and combined group was higher than that in the model group(P<0.01).The levels of TLR9 mRNA and protein in rat spinal cord of the model group increased significantly,while which in the electroacupuncture group,Pain Sticker group and combined group was decreased significantly compared with the model group(P<0.01).Conclusion Electroacupuncture combined with Pain Sticker has the effect for relieving pain in the rats with bone cancer pain,and its mechanism is related to the decrease in expression of TLR9.