孫永欣 姚剛 于挺敏 滿玉紅
[摘要] 緊張型頭痛(TTH)是最常見的原發(fā)性頭痛類型,目前對其仍缺少足夠重視。外周致敏、顱周肌肉壓痛及肌肉的異?;顒印⒅袠猩窠浵到y(tǒng)疼痛調節(jié)機制異常、細胞因子及炎性介質的代謝紊亂等因素可能從不同方面參與了TTH的發(fā)病過程。電生理技術、神經影像技術及檢驗技術為TTH發(fā)病機制的研究提供了有效手段。本文對TTH可能的發(fā)病機制及相應研究進展進行簡要概括,以期加深對此疾病的了解,為基礎研究及臨床診療提供參考。
[關鍵詞] 緊張型頭痛;機制;外周致敏;中樞疼痛調節(jié)
[中圖分類號] R255? ? ? ? ? [文獻標識碼] A? ? ? ? ? [文章編號] 1673-7210(2019)01(c)-0037-04
[Abstract] Tension-type headache (TTH) is the most common type of primary headache, which is still lacking enough attention. Factors such as peripheral sensitization, craniocerebral muscle tenderness and abnormal muscle activity, abnormal regulation mechanism of central nervous system pain, cytokines and metabolic disorders of inflammatory mediators may participate in the pathogenesis of TTH from different aspects. Electrophysiological techniques, neuroimaging techniques and testing techniques provide an effective means for the study of the pathogenesis of TTH. This article briefly summarizes the possible pathogenesis of TTH and the corresponding research progress, in order to deepen the understanding of this disease, and provide reference for basic research and clinical diagnosis and treatment.
[Key words] Tension-type headache; Pathogenesis; Peripheral sensitization; Central pain regulation
緊張型頭痛(tension-type headache,TTH)在國際頭痛疾病分類第三版(ICHD-3)中被歸類為原發(fā)性頭痛,其根據頭痛每月發(fā)作頻率可分為偶發(fā)性緊張型頭痛(infrequent episodic tension-type headache,IETTH)、頻發(fā)性緊張型頭痛(frequent episodic tension-type he-adache,F(xiàn)ETTH)及慢性緊張型頭痛(chronic tension-type headache,CTTH)[1],是最為常見的原發(fā)性頭痛。TTH的年患病率僅次于齲齒和潛伏性結核感染,位列第三位[2],而全球頭痛負擔調查[3]顯示,TTH的年患病率為11%~45%。目前,TTH的發(fā)病機制尚未完全闡明,多種因素可能參與其中。本文簡要綜述了TTH可能的發(fā)病機制及研究進展,以期為其臨床治療提供參考。
1 觸痛點和外周致敏
觸痛點(triger points,TrPS)是骨骼肌緊張帶中對壓力高度敏感的區(qū)域,當受到刺激時,可引起局部疼痛或遠隔部位的牽涉痛[4]。與TTH有關的TrPS主要分布在三叉神經支配的顳肌、咬肌以及C1-C3支配的斜方肌、胸鎖乳突肌[5]。ETTH患者頭頸部肌肉TrPS反復注射利多卡因后,頭痛持續(xù)時間縮短,疼痛程度降低[6],提示TrPS在TTH的發(fā)展過程中起到重要作用。CTTH患者斜方肌TrPS周圍1~2 mm內可見持續(xù)性自發(fā)肌電活動,認為這種肌電活動源自梭內肌纖維的持續(xù)收縮[7]。另有研究[8]顯示,TrPS處致痛性化學因子如5-羥色胺(5-hydroxytryptamine,5-HT)、緩激肽(bradykinin,BK)、降鈣素基因相關肽(calcitoningene related peptide,CGRP)、P物質(substance P,SP)等的濃度顯著升高。由此可見,TrPS處持續(xù)的低水平肌肉活動可能會損害肌肉纖維,引起局部致痛物質的聚集,進而刺激外周傷害性感受器導致疼痛。外周傷害性感受器為游離神經末梢,主要分布在骨骼肌、動脈壁和結締組織中,由Aδ類或C類神經纖維介導[9]。致痛物質可提高外周傷害性感受器的興奮性,降低其反應閾值,即產生外周致敏效應,參與TTH的發(fā)生。外周傷害性感受器痛覺信息的持續(xù)傳入可引起中樞神經系統(tǒng)的敏化,進而導致TTH的慢性化。
2 顱周肌肉壓痛和頭頸部肌肉異?;顒?/p>
Jensen等[10]通過對58例TTH患者及30例健康對照進行持續(xù)30 min咬合試驗,發(fā)現(xiàn)68%的TTH患者和17%的健康人可在24 h內誘發(fā)出頭痛,且顱周肌肉壓痛值在頭痛發(fā)生之前即增高,在未誘發(fā)出現(xiàn)頭痛的患者中,顱周肌肉壓痛值保持穩(wěn)定,認為顱周肌肉壓痛先于頭痛出現(xiàn)并可能導致頭痛。但也有研究[11]發(fā)現(xiàn),CTTH患者頭痛發(fā)作之前,顱周肌肉壓痛值可保持正常水平。Mingels等[12]一項針對女性ETTH患者的橫斷面研究顯示,ETTH患者在頭痛發(fā)作間期顱周肌肉壓痛值明顯增加,且與每月疼痛發(fā)作頻率有關,與頭痛程度及持續(xù)時間無關。顱周肌肉壓痛值增加可能和外周致敏及中樞神經系統(tǒng)疼痛調節(jié)功能障礙有關[13],但顱周肌肉壓痛值增加是導致頭痛的原因還是頭痛繼發(fā)性表現(xiàn)目前仍需進一步研究證實。頭頸部肌肉異?;顒右部赡軈⑴cTTH的發(fā)生。研究[14]顯示,與健康對照組比較,CTTH患者在頸部屈伸運動時,拮抗肌的肌電活動顯著增強,這可能導致肌肉負荷增加,促進傷害性信息的傳入,從而參與頭痛產生。
3 中樞疼痛調節(jié)機制異常
中樞神經系統(tǒng)疼痛調節(jié)機制的異常可能參與了TTH的痛覺維持及慢性化。外周感受抑制實驗(exteroceptive suppression,ES)被認為是研究TTH疼痛中樞調控機制的有效方案,該實驗通過對三叉神經第1、2支分布區(qū)進行電或機械刺激引起咀嚼肌自主收縮活動反射性抑制,其在肌電圖(EMG)上表現(xiàn)為第一外感受抑制期(ES1)(產生于刺激后10~20 ms)和第二外感受抑制期(ES2)(產生于刺激后45~55 ms),其中,ES1屬腦干內少突觸環(huán)路反射,而ES2屬多突觸環(huán)路反射,其活動受邊緣系統(tǒng)調控。CTTH患者ES2時限縮短,而ETTH患者ES2時限正常,提示腦干抑制性中間神經元活動不良或被抑制過度,從而導致邊緣系統(tǒng)發(fā)放的沖動傳導不良或被阻斷[15],客觀上反映了CTTH患者中樞性疼痛調控機制異常。通過對ES2的藥理調控研究[15],發(fā)現(xiàn)介導ES2的抑制性中間神經元可被5-羥色胺能傳導通路抑制,阿米替林(5-HT再攝取抑制劑)可縮短CTTH患者ES2時限。CTTH患者傷害性屈曲反射(nociceptive flexion reflex,NFR)的反應閾值及痛覺耐受閾值較健康對照組明顯降低,提示中樞內源性下行疼痛調控系統(tǒng)功能不良[16]。NFR由脊髓介導,受中樞神經系統(tǒng)下行疼痛調節(jié)系統(tǒng)調控。上述觀點還可通過對彌漫性傷害刺激抑制性控制(diffuse noxious inhibitory controls,DNIC)的研究進一步證實。Sandrini等[17]對CTTH患者進行冷壓試驗,發(fā)現(xiàn)將CTTH患者一側上肢浸入5~6℃的冷水后對其對側股二頭肌進行電刺激,NFR呈現(xiàn)易化,其反應閾值較基礎值降低,提示DNIC效應減弱,客觀反映了中樞疼痛調節(jié)系統(tǒng)的異常。
Schmidt-Wilcke[18]通過核磁平掃及象素分析發(fā)現(xiàn),CTTH患者大腦中參與疼痛處理的區(qū)域(包括扣帶回前部、島葉、額葉皮質、海馬旁回等)灰質體積較健康人明顯減小,減小程度與頭痛持續(xù)時間呈正相關,并認為這一改變是中樞神經系統(tǒng)敏化的結果。上述區(qū)域灰質體積的減少可能反映了抑制性下行疼痛調節(jié)系統(tǒng)功能受損,但這一結果仍有待進一步研究證實。
4 神經遞質及炎性因子代謝紊亂
5-HT廣泛參與中樞神經系統(tǒng)疼痛調控。Bendtsen等[19]研究發(fā)現(xiàn),ETTH患者血小板5-HT水平升高,而其在CTTH患者中降低,但血漿5-HT水平在ETTH患者中升高,在CTTH患者中則保持正常,其認為這一現(xiàn)象與ETTH患者中樞疼痛抑制系統(tǒng)代償有關,而在CTTH患者的這種代償能力可能不足,進而促進了頭痛的維持。另有文獻[20]報道,CTTH患者在接受靜脈注射一氧化氮合成酶抑制劑L-單甲基精氨酸后,疼痛程度較安慰劑組降低,提示一氧化氮可能參與TTH的發(fā)展。一氧化氮可使傳入神經末梢釋放遞質增加,局部前列腺素聚集,提高突觸后膜N-甲基-D-天冬氨酸受體反應性,進而引起脊髓背角神經元的活化,促進痛覺信息的傳遞[21]。
炎性細胞因子也可能參與TTH的產生和維持。Della等[22]通過測定56例CTTH患者及42名健康對照的血清炎性細胞因子濃度發(fā)現(xiàn),CTTH患者血清中白細胞介素-1β(interleukin-1β,IL-1β)濃度較對照組顯著升高。另有報道[23],CTTH患者IL-6的濃度也較健康對照組升高,但差異無統(tǒng)計學意義。鞏曉英等[24]研究發(fā)現(xiàn),TTH患者血清IL-8水平較健康對照組顯著升高,且IL-8水平與疼痛視覺模擬評分呈正相關。外周炎性細胞因子水平的升高可提升外周感受神經元的活性,進而促進痛覺信息的傳遞,并參與中樞神經系統(tǒng)敏化。Neeb等[25]研究發(fā)現(xiàn),IL-1β可通過環(huán)氧酶(COX)途徑誘導降鈣素基因相關肽(CGRP)在三叉神經節(jié)細胞中的合成,參與中樞神經系統(tǒng)血管炎性反應及肥大細胞的釋放,進而參與頭痛的痛覺維持。然而,炎性細胞因子和TTH的關系仍有待深入研究。
綜上所述,TTH的發(fā)病機制較為復雜,某些具體機制尚需進一步研究。值得注意的是,由于TTH的臨床癥狀較偏頭痛等其他頭痛癥狀較輕,臨床醫(yī)生及患者對該病關注均相對較少,從而導致對該病認識不足,易發(fā)生錯誤的診斷及治療,這可能會導致患者反復就醫(yī),進而對患者身心造成傷害[26-27]。目前,隨著技術手段的發(fā)展及對疾病認識的不斷深入,TTH、偏頭痛等其他頭痛的治療手段正逐步多樣化[28-30]。通過對TTH發(fā)病機制的探討,有助于進一步加深對該病的了解,為相關基礎研究及臨床工作提供參考。
[參考文獻]
[1]? Olesen J. International Classification of Headache Disorders [J]. Lancet Neurol,2018,17(5):396-397.
[2]? Vos T,Abajobir AA,Abate KH,et al. Global,regional,and national incidence,prevalence,and years lived with disability for 328 diseases and injuries for 195 countries,1990-2016:a systematic analysis for the Global Burden of Disease Study 2016 [J]. Lancet,2017,390(10 100):1211-1259.
[3]? Saylor D,Steiner TJ. The Global Burden of Headache [J]. Semin Neurol,2018,38(2):182-190.
[4]? Do TP,Heldarskard GF,Kolding LT,et al. Myofascial trigger points in migraine and tension-type headache [J]. J Headache Pain,2018,19(1):84.
[5]? Bendtsen L,Ashina S,Moore A,et al. Muscles and their role in episodic tension-type headache:implications for treatment [J]. Eur J Pain,2016,20(2):166-175.
[6]? Berk T,Silberstein SD. The Use and Method of Action of Intravenous Lidocaine and Its Metabolite in Headache Disorders [J]. Headache,2018,58(5):783-789.
[7]? Arendt-Nielsen L,Castaldo M,Mechelli F,et al. Muscle triggers as a possible source of pain in a subgroup of tension-type headache patients?[J]. Clin J Pain,2016,32(8):711-718.
[8]? Ziaeifar M,Arab AM,Nourbakhsh MR. Clinical effectiveness of dry needling immediately after application on myofascial trigger point in upper trapezius muscle [J]. J Chiropr Med,2016,15(4):252-258.
[9]? Palacioscea,MCastaldo M,Wang K,et al. Relationship of active trigger points with related disability and anxiety in people with tension-type headache [J]. Medicine,2017,96(8):e6548.
[10]? Jensen R,Olesen J.Initiating mechanisms of experimentally induced tension-type headache [J]. Cephalalgia,1996, 16(13):175-182.
[11]? Buchgreitz L,Lyngberg AC,Bendtsen L,et al. Increased prevalence of tension-type headache over a 12-year period is related to increased pain sensitivity. A population study [J]. Cephalalgia,2007,27(2):145-152.
[12]? Mingels S,Granitzer M. Pericranial Tenderness in Females With Episodic Cervical Headache vs Asymptomatic Controls:A Cross-sectional Study [J]. J Manipulative Physiol Ther,2018,41(6):488-495.
[13]? Burstein R,Blake P,Schain A,et al. Extracranial origin of headache [J]. Curr Opin Neurol,2017,30(3):263-271.
[14]? Madsen BK,Sgaard K,Andersen LL,et al. Neck/shoulder function in tension-type headache patients and the effect of strength training [J]. J Pain Res,2018,11:445.
[15]? Vandenheede M,Schoenen J. Central mechanisms in tension-type headaches [J]. Curr Pain Headache Rep,2002, 6(5):392-400.
[16]? Jay GW,Barkin RL. Primary Headache Disorders-Part 2:Tension-type headache and medication overuse headache [J]. Dis Mon,2017,63(12),342-367.
[17]? Sandrini G,Rossi P,Milanov I,et al. Abnormal modulatory influence of diffuse noxious inhibitory controls in migraine and chronic tension-type headache patients [J]. Cephalalgia,2006,26(7):782-789.
[18]? Schmidt-Wilcke T. Neuroimaging of chronic pain [J]. Best Pract Res Clin Rheumatol,2015,29(1):29-41.
[19]? Bendtsen L,Jensen R,Hindberg I,et al. Serotonin met-abolism in chronic tension-type headache [J]. Cephalalgia,1997, 17(8):843-848.
[20]? Ashina M,Lassen LH,Bendtsen L,et al. Effect of inhibition of nitric oxide synthase on chronic tension-type headache:a randomised crossover trial [J]. Lancet,1999, 353(9149):287-289.
[21]? Choi SR,Kwon SG,Choi HS,et al. Neuronal NOS activates spinal NADPH oxidase 2 contributing to central sigma-1 receptor-induced pain hypersensitivity in mice [J]. Biol Pharm Bull,2016,39(12):1922-1931.
[22]? Della VC,Cathcart S,Dohnalek A,et al. Peripheral interleukin-1β levels are elevated in chronic tension-type headache patients [J]. Pain Res Manag,2013,18(6):301-306.
[23]? Rambe AS,Sjahrir H,Machfoed MH. Tumour Necrosis Factor-Α,Interleukin-1 and Interleukin-6 Serum Levels and Its Correlation with Pain Severity in Chronic Tension-Type Headache Patients:Analysing Effect of Dexketoprofen Administration [J]. Open Access Maced J Med Sci,2017,5(1):54.
[24]? 鞏曉英,胥冰,張麗.緊張型頭痛患者血清IL-8水平的變化及其臨床意義[J].西南國防醫(yī)藥,2017(12):1271-1273.
[25]? Neeb L,Hellen P,Hoffmann J,et al. Methylprednisolone blocks interleukin 1 beta induced calcitonin gene related peptide release in trigeminal ganglia cells [J]. J Headache Pain,2016,17(1):19.
[26]? 李娜,杜衍君,邢舒平,等.388例緊張型頭痛病人臨床分析[J].中國疼痛醫(yī)學雜志,2018(1):71-74.
[27]? 鐘傳飄.慢性非器質性頭痛及焦慮抑郁情緒的關系分析[J].中國醫(yī)藥科學,2018,8(2):180-182,194.
[28]? 邱芳暉,陳淑萍.刺血療法結合電針治療偏頭痛的臨床研究[J].中國現(xiàn)代醫(yī)生,2018,56(15):127-130.
[29]? 胡文舉,孟志劍.活血祛風通絡湯聯(lián)合針灸治療神經性頭痛的療效觀察[J].中國醫(yī)院用藥評價與分析,2017, 17(2):184-185,188.
[30]? 鐘希文,鐘遠輝,鄒增業(yè).社區(qū)頸舒顆粒、西比靈聯(lián)合治療緊張性頭痛78例臨床觀察[J].中國醫(yī)藥科學,2018, 8(7):233-235,250.
(收稿日期:2018-09-30? 本文編輯:王? ?蕾)