Objective: To observe the effects of moxibustion at "Baihui" (GV 20) and "Dazhui" (GV 14) at different time points on the serum level of β-endorphin (β-EP), substance P (SP) and expression of interleukin-1β (IL-1β) and cyclooxygenase-2 (COX-2) protein in brainstem in rats with migraine, and to explore the effect and mechanism of moxibustion in preventing and treating migraine.
Methods: Forty male SD rats were randomly divided into a blank group, a model group, a prevention+treatment (PT) group and a treatment group, 10 rats in each group. Except the blank group, the rats in the remaining groups were injected with nitroglycerin subcutaneously to prepare migraine model. The rats in the PT group were treated with moxibustion 7 days before modeling (once a day) and 30 min after modeling, while the rats in the treatment group were treated with moxibustion 30 min after modeling. The "Baihui" (GV 20) and "Dazhui" (GV 14) were taken for 30 minutes each time. The behavioral scores in each group were observed before and after modeling. After intervention, ELISA method was used to detect the serum level of β-EP and SP; the immunohistochemistry method was used to detect the number of positive cells of IL-1β in brainstem; the Western blot method was used to detect the expression of COX-2 protein in brainstem.
Results: Compared with the blank group, the behavioral scores in the model group were increased 0-30 min, 60-90 min and 90-120 min after modeling (P<0.01); compared with the model group, in the treatment group and the PT group, the behavioral scores were decreased 60-90 min and 90-120 min after modeling (P<0.01). Compared with the blank group, in the model group, the serum level of β-EP was decreased (P<0.01), while the serum level of SP, the number of positive cells of IL-1β in brainstem and the expression of COX-2 protein were increased (P<0.01). Compared with the model group, in the PT group and and the treatment group, the serum level of β-EP was increased (P<0.01), while the serum level of SP, the number of positive cells of IL-1β and the expression of COX-2 protein in brainstem were decreased (P<0.01, P<0.05). Compared with the treatment group, in the PT group, the serum level of β-EP was increased and COX-2 protein expression was decreased (P<0.05).
Conclusion: Moxibustion could effectively relieve migraine. The mechanism may be related to reduce the serum level of SP, IL-1β and COX-2 protein expression in brainstem, and increase the serum level of β-EP, and the optimal effect is observed in the PT group.
目的：观察不同时间艾灸“百会”“大椎”对偏头痛大鼠血清β-内啡肽（β-EP）、P物质（SP）含量及脑干白介素-1β（IL-1β）、环氧合酶2（COX-2）蛋白表达的影响，探讨艾灸防治偏头痛的作用及机制。方法：将40只雄性SD大鼠随机分为空白组、模型组、预防+治疗组和治疗组，每组10只。除空白组外，其他各组大鼠采用硝酸甘油皮下注射制备偏头痛模型。预防+治疗组于造模前7 d（每日1次）及造模后30 min予艾灸干预，治疗组于造模后30 min予艾灸干预，均穴取“百会”“大椎”，每次30 min。观察各组大鼠造模前后行为学评分。干预结束后，采用ELISA法检测各组大鼠血清β-EP、SP含量，免疫组化法检测各组大鼠脑干IL-1β阳性细胞数，Western blot法检测各组大鼠脑干COX-2蛋白表达。结果：与空白组比较，模型组大鼠造模后0~30 min、60~90 min、90~120 min行为学评分升高（P<0.01）；与模型组比较，治疗组、预防+治疗组大鼠造模后60~90 min、90~120 min行为学评分降低（P<0.01）。与空白组比较，模型组大鼠血清β-EP含量降低（P<0.01），血清SP含量、脑干IL-1β阳性细胞数及COX-2蛋白表达均升高（P<0.01）；与模型组比较，预防+治疗组和治疗组大鼠血清β-EP含量升高（P<0.01），血清SP含量、脑干IL-1β阳性细胞数及COX-2蛋白表达均降低（P<0.01，P<0.05）；与治疗组比较，预防+治疗组大鼠血清β-EP含量升高、COX-2蛋白表达降低（P<0.05）。结论：艾灸可有效缓解偏头痛。其机制可能为降低大鼠血清SP含量、脑干IL-1β和COX-2蛋白表达，升高血清β-EP含量，预防+治疗干预的效果最佳。.
Keywords: Point GV 14 (Dazhui); Point GV 20 (Baihui); cyclooxygenase-2 (COX-2); interleukin-1β (IL-1β); migraine; moxibustion; substance P (SP); β-endorphin (β-EP).