切换中文 维普资讯 中国知网 万方数据
Preclinic Research | Updated:2024-02-22
    • Up-regulation of Proinflammatory Cytokines in Rostral Ventromedial Medulla Contributes to Chronic Postsurgical Pain by Promoting 5-HT Release

    • DAI Juanli

      ,  

      WANG Zhen

      ,  

      DONG Chaoxiong

      ,  

      LI Yuying

      ,  

      WEI Xuhong

      ,  
    • Journal of Sun Yat-sen University(Medical Sciences)   Vol. 45, Issue 1, Pages: 54-62(2024)
    • DOI:10.13471/j.cnki.j.sun.yat-sen.univ(med.sci).20240004.005    

      CLC: R338.8
    • Published:20 January 2024

      Received:26 August 2023

      Accepted:03 December 2023

    Scan for full text

  • Cite this article

    PDF

  • DAI Juanli,WANG Zhen,DONG Chaoxiong,et al.Up-regulation of Proinflammatory Cytokines in Rostral Ventromedial Medulla Contributes to Chronic Postsurgical Pain by Promoting 5-HT Release[J].Journal of Sun Yat-sen University(Medical Sciences),2024,45(01):54-62. DOI: 10.13471/j.cnki.j.sun.yat-sen.univ(med.sci).20240004.005.

  •  
  •  
    Sections

    Abstract

    Objective

    To investigate the role of proinflammatory cytokines tumor necrosis factor alpha (TNFα) and interleukin-1β (IL-1β) in rostral ventromedial medulla (RVM) in chronic postsurgical pain (CPSP) induced by skin/muscle incision and retraction (SMIR).

    transl

    Methods

    SD rats were randomly divided into 5 groups: ① Sham group; ② SMIR group; ③ SMIR+TNFα/IL-1β neutralizing antibody group; ④ SMIR+TNFα/IL-1β group and ⑤ SMIR+vehicle group. 50% paw mechanical withdrawal threshold (MWT) was measured by the up-down method, immunofluroscence was used to detect the TNFα and IL-1β expression and ELISA for the 5-Hydroxytryptamine (5-HT) level.

    transl

    Results

    SMIR elicited persistent nociceptive sensitization, upregulated TNFα and IL-1β expression in RVM neurons and astrocytes. Microinjection of TNFα or IL-1β neutralizing antibody into RVM inhibited the development of nociceptive sensitization and decreased the level of 5-HT in both RVM and spinal dorsal horn. While microinjection of recombinant TNFα or IL-1β into RVM enhanced the development of nociceptive sensitization and increased the level of 5-HT in both RVM and spinal dorsal horn.

    transl

    Conclusion

    Up-regulation of proinflammatory cytokines in RVM may contribute to SMIR induced CPSP by promoting 5-HT release.

    transl

    Keywords

    chronic postoperative pain (CPSP); rostral ventromedial medulla (RVM); tumor necrosis factor alpha (TNFα); interleukin-1β (IL-1β); 5-Hydroxytryptamine (5-HT)

    transl

    外科手术如腹股沟疝修补手术或开胸手术后,约10%~50%的患者会产生慢性术后疼痛(chronic postoperative pain, CPSP)。其表现为在手术过后2个月,手术切口部位仍持续性疼痛,且不存在慢性感染,皮肤切口愈合不良等情况。CPSP对身体健康,日常活动,心理健康,就业和经济情况具有显著有害影响。在所有的接受手术的病人中有 0.5%~1.5% 的病人患有严重的甚至是致残性的 CPSP

    1 ,因手术类型的不同而有所差异。因此,慢性术后疼痛不是一种伴随伤口恢复就可以消失的症状。目前仍然缺乏对这类疼痛的认识、诊断和治疗,因此非常有必要阐明CPSP的发病机制,从而为进一步预防或治疗CPSP提供指导依据。研究报道,牵拉大鼠隐神经支配的大腿皮肤/肌肉可导致远隔部位——后爪上产生了机械痛敏,被牵拉的隐神经并没有出现显著的损伤2-3,但却在脊髓背角出现了星形胶质细胞的激活。提示中枢敏感化可能是CPSP的发生的重要原因。延髓头端腹内侧区(rostral ventromedial medullar, RVM)是疼痛调控通路的重要区域,其接受下丘脑、中脑导水管周围灰质、臂旁核等的投射,并通过脊髓腹外侧束和脊髓背外侧束对疼痛发挥抑制或易化调节作用。RVM是疼痛下行易化系统的重要区域,研究表明,RVM 的5-羟色胺(5-hydroxytryptamine ,5-HT)能神经元可被伤害性刺激激活后释放5-HT到脊髓,参与中枢敏感化的产生,因而对调节伤害性刺激相关的行为反应具有重要作用4。实验研究表明,慢性神经病理痛的产生发展, 有赖于下行易化系统的激活。阻断RVM的下行易化作用可显著减轻神经病理性疼痛5-6。致炎细胞因子的释放是引起下行易化系统的激活的关键因素。越来越多的证据表明神经损伤过后或癌性痛时,RVM(由功能类似的中缝大核、网状巨细胞核和网状巨细胞核 α 部组成)产生了与脊髓相似的小胶质细胞激活反应7-8,而小胶质细胞激活会导致炎性因子如 肿瘤坏死因子α(tumor necrosis factor alpha,TNFα)和白介素-1β(interleukin-1β,IL-1β)的释放,继而导致病理性疼痛的产生9-10。中和 RVM 的致炎细胞因子 TNFα 或敲除脑源性神经营养因子(brainderivedneurotrophicfactor,BDNF)受体 TrkB 可以减轻神经损伤或炎症引起的痛行为,而 RVM 局部注射 TNFα 可引起痛敏811。 但TNFα 及 IL-1β是否通过引起RVM 5-HT释放增多进而导致术后痛尚不清楚。本项目拟观察皮肤/肌肉切开和牵拉(skin/muscle incision and retraction ,SMIR) 大鼠疼痛模型导致的病理性疼痛产生过程中RVM TNFα 及 IL-1β表达的变化情况,观察TNFα 及 IL-1β中和性抗体是否阻断SMIR引起的机械痛敏及对RVM、脊髓背角 5-HT含量的影响,以此探讨RVM致炎细胞因子因子是否通过促进5-HT向脊髓的释放来参与调控CPSP的发生发展。
    transl

    1 材料与方法

    1.1 实验动物

    成年Sprague-Dawley (SD) 大鼠,雌雄不限,体质量220 ~ 250 g,购于中山大学北校区实验动物中心(国家级动物实验中心)提供。动物的使用协议和动物处理程序获得了中山大学实验动物管理与使用委员会(IACUC)的批准。动物饲养于室温(22 ± 0.5)℃、湿度50%-60%、12 h 黑暗-光照循环照明的安静环境。单笼饲养,自由饮水摄食。动物随机分配到不同的实验组。实验动物适应环境一周后,随机将74只大鼠随机分为:假手术 (17只)、SMIR (22只)、SMIR+vehicle(5只)、 SMIR+TNFɑ(或IL-1β中和性抗体,10只)、vehicle (10只)、 TNFɑ(或IL-1β, 10只)组。我们没有使用统计方法,而是基于以前我们的经验

    36来确定样本量。
    transl

    1.2 皮肤/肌肉切开和牵拉(SMIR)模型手术

    将动物用异氟烷(1.5%-2.5%)、70%O2和30%N2O的混合物麻醉,在大鼠左侧后大腿内侧靠近隐静脉处大约4 mm远的皮肤表面做1.5-2 cm的切口,暴露大腿肌肉后,在肌肉浅层做7-10 mm的切口,插入微型解剖牵开器(Biomedical Research Instruments Inc.,USA)。将大腿的皮肤及浅表肌肉牵拉2 cm并持续1 h(如图1)。 假手术组只皮肤切开但不进行牵拉。

    transl

    fig

    图1  皮肤/肌肉牵拉引起大鼠50%机械刺激撤足阈值下降

    Fig.1  Skin/muscle and incision (SMIR) decreased the 50% paw withdrawal threshold

    A-D :surgery procedure E:Compared to the sham group, the 50% paw withdrawal threshold was significantly decreased for 21 days in SMIR rats but not in sham rats. day 1, Z=-3.252, P=0.001; day 3, Z=-3.255, P=0.001; day 5, Z=-3.249, P=0.001; day 7, Z=-3.216, P=0.001, day 14, Z=-3.252, P=0.001; day 21, Z=-2.674, P=0.001; day 35, Z=-1.854, P=0.007 2. **P<0.01,*** P<0.001 compared with sham group. n=7 /group.

    icon Download:  Full-size image | High-res image | Low-res image

    1.3 50%机械刺激撤足阈值的测定

    具体操作方法参照我们之前的操作

    12
    transl

    1.4 RVM置管给药注射药物

    为了将药物显微注射入RVM,我们使用戊巴比妥钠麻醉大鼠,并将其置于脑立体定位仪上。具体操作方法参照我们之前的操作

    12。注射位点不正确的动物被排除。
    transl

    1.5 动物灌注及标本处理

    具体操作方法参照我们之前的操作

    12
    transl

    1.6 免疫荧光组织化学染色

    脑冰冻切片用0.01 mol/L PBS洗片3次,每次5 min,室温(25 ℃)下加入封闭液以封闭非特异性结合位点,1 h后弃去封闭液,加入含有待检测蛋白抗体(TNF-α抗体或IL-1β抗体,1 : 400或 1 : 200)的一抗稀释液,置于4 ℃摇床过夜。吸去一抗,洗片3次,每次10 min, 随后加入荧光二抗,室温(25 ℃)下避光摇床上慢摇1 h。弃去二抗, 洗片3次,每次10 min。随机挑选切片贴于载玻片上,封片后立即于荧光显微镜(LEICA DFC350 FX Camera,Germany)下观察并拍照保存。半定量分析使用Image J 软件,每组每只动物随机挑选5张切片,每组动物数n = 5, 计算出每张切片RVM区域的免疫荧光阳性面积,再比上RVM的总面积,得到免疫荧光阳性面积百分比。

    transl

    1.7 酶联免疫吸附测定法 (ELISA)方法观察RVM及脊髓背角内5-HT含量

    迅速提取脊髓背角L3处和脑组织RVM部分,具体操作方法参照我们之前的操作

    12
    transl

    1.8 统计学分析

    统计分析使用 SPSS 16.0统计分析软件,实验结果以均数 ± 标准误(Mean± SEM)表示,p<0.05则认为有统计学差异。行为学测试结果因不符合正态分布,均采用非参数检验进行分析。所有定量资料满足正态分布,且通过方差齐性检验后采用单因素方差分析,否则采用非参数检验。两个不同实验组同一时间点的数据比较采用Mann-Whitney U检验。免疫荧光光密度,ELISA测得的5-HT 浓度数据在满足正态分布,且通过方差齐性检验后采用单因素方差分析(one-way ANOVA),组间差异用Tukey法(Tukey post hoc test)检测。

    transl

    2 结 果

    2.1 SMIR 引起长时间的机械痛敏

    行为学测试发现,与手术前基础值或与假手术组比较,隐神经支配部位的皮肤及肌肉牵拉持续1 h后(图1A-D),大鼠同侧后肢50%机械刺激撤足阈值于手术后1 d显著下降(P<0.01),7 d降至最低点(P<0.001),显著性差异一直保持至术后21 d左右(图1E)。说明SMIR可引起较长时间的术后机械痛敏。

    transl

    2.2 SMIR 引起RVM内TNFα及IL-1β表达上调

    TNF-α是神经损伤以及神经炎症过程最重要和最早释放的致炎细胞因子

    13,其能进一步促进其他细胞因子(如IL-1β、IL-6 等)的产生。我们之前的研究表明,脊髓背角IL-1β14和IL-615 均在神经损伤引起的病理性疼痛的产生和维持过程发挥着重要作用。因此本研究探讨了RVM 具有代表性的两个致炎细胞因子 TNF-α和IL-1β在SMIR 引起的慢性术后疼痛中的作用。因SMIR术后1 d时50%机械刺激阈值刚刚开始下降,属于疼痛的产生阶段。7 d时50%机械刺激阈值降至最低水平,之后开始逐渐恢复,本研究选取1 d和14 d作为代表性的两个时间点来进行分子生物学的观察。
    transl

    免疫组化实验结果表明,SMIR可引起RVM内TNFα表达上调,如图2所示,与假手术组(图2A D)相比,SMIR术后1 d时TNFα的免疫荧光密度已显著上调(图2B-D),7 d时进一步上调(图2C-D)。同样的,IL-1β的免疫荧光密度也呈现出与TNFα类似的变化(图2E-H)。免疫荧光双染实验发现,SMIR 7 d时,上调的TNFα及IL-1β主要位于NeuN标记的神经元(图3A-C J-L),但GFAP标记的星形胶质细胞(图3D-F M-O)以及Iba1标记的小胶质细胞内(图3G-I P-R)也有少量表达。

    transl

    fig

    图2  皮肤/肌肉牵拉对RVM TNFα及IL-1β 表达的影响

    Fig.2  The effect of SMIR on the expression of TNFα及IL-1βin RVM

    Compared to the sham group, SMIR upregulated the expression of TNFα(A-D)及IL-1β(E-H) at day 1 and 7 (n=5/group).D: F (2, 12)=22.09, P<0.001, *** P =0.000 2 at SMIR 1d and 7 d compared with sham group. H: F(2, 12)=20.14, P=0.000 1, ***P =0.000 3 at SMIR 1 d,***P=0.000 2 at SMIR 7 d compared with sham group.

    icon Download:  Full-size image | High-res image | Low-res image
    fig

    图3  SMIR 后7 d RVM内TNFα及IL-1β表达的细胞类型

    Fig. 3  The cell types that expressed TNFα及IL-1β 7 days after SMIR

    TNFα was expressed mostly in NeuN labeled neurons (A-C), and to a much lesser extent in GFAP marked astrocyte (D-F) and Iba1 marked microglia (G-I) in RVM at day 7 after SMIR. IL-1β was expressed mostly in NeuN labeled neurons (J-L), and to a much lesser extent in GFAP marked astrocyte (M-O) and Iba1 marked microglia (P-R) in RVM at day 7 after SMIR. n=3/group.

    icon Download:  Full-size image | High-res image | Low-res image

    2.3 预先RVM内给予TNFα或IL-1β中和性抗体可防止SMIR引起的机械痛敏

    上述结果表明SMIR手术导致了RVM内TNFαIL-1β表达的上调,那么致炎细胞因子的上调与疼痛产生之间的关系又是怎样的呢?为此我们在RVM内分别微量注射了TNFα中和性抗体(100 pg,1 μL,每天1次,SMIR术前30 min开始,共4次)或IL-1β中和性抗体(100 pg,1 μL,SMIR术前30 min开始,每天1次,共4次),结果发现其均可阻断SMIR引起的机械痛敏,而给予对照溶剂则无作用,SMIR后50%机械刺激撤足阈值仍然出现下降(图4A-B)。ELISA实验进一步发现,SMIR后7 d的RVM和脊髓背角内5-HT的含量均显著增加。与给予溶剂组相比,给予TNFα或IL-1β的中和性抗体显著降低了RVM内和脊髓背角内神经递质5-HT的含量(图4C-D)。给予溶剂对SMIR引起的5-HT释放影响不大。该结果提示SMIR后RVM内致炎细胞因子的释放可能通过引起脊髓内5-HT释放增多进而引起慢性术后疼痛。

    transl

    fig

    图4  RVM内注射TNFα或IL-1β中和性抗体对SMIR引起的机械痛敏及5-HT水平的影响

    Fig.4  The effect of TNFα or IL-1β neutralizing antibody on the nociceptive sensitization and 5-HT level in RVM and spinal cord induced by SMIR

    A: Compared to the vehicle group, microinjection of TNFα neutralizing antibody into RVM inhibited the development of nociceptive sensitization .day -1, Z=-8.383, P=0.421; day 1, Z=-2.41, P=0.016; day 3, Z=-2.611, P=0.09;day 5, Z=-2.611, P=0.09; day 7, Z=-2.643, P=0.008, day 9, Z=-Z=-2.643, P=0.008. B : Compared to the vehicle group , microinjection of IL-1β neutralizing antibody into RVM inhibited the development of nociceptive sensitization. C-D :the effect of TNFα or IL-1β neutralizing antibody on the 5-HT level in RVM (C) and spinal dorsal horn(D) C: F(4, 20)=69.25, P<0.0001, ***P<0.001, SMIR+TNF antibody group ( the 5-HT level was significantly decreased ) compared with SMIR+vehicle group.***P<0.001, SMIR+IL-1 antibody group ( the 5-HT level was significantly decreased ) compared with SMIR+vehicle group . **P<0.01,***P<0.001 compared with the related group. n=5/group.

    icon Download:  Full-size image | High-res image | Low-res image

    2.4 RVM内注射TNFα或IL-1β可引起正常动物机械痛敏及5-HT释放增多。

    我们进一步观察了RVM内TNFα或IL-1β是否是引起机械痛敏的充分条件。发现RVM内微量注射TNFα或IL-1β均可引起机械痛敏(图5A-B)。ELISA实验进一步证实,注射TNFα或IL-1β 也可引起5-HT释放增多(图5C-D)。

    transl

    fig

    图5  RVM 内微量注射TNFα或IL-1β对正常动物50%机械刺激撤足阈值及RVM 内和脊髓背角神经递质5-HT含量的影响

    Fig.5  The effect of microinjection of TNFα or IL-1β into RVM of naive rats on the 50% paw withdrawal threshold and the level of 5-HT in RVM and spinal dorsal horn

    A-B:The effect of microinjection of TNFα or IL-1β into RVM of naïve rats on the 50% paw withdrawal threshold A: day -1, Z=-2.643, P=0.008; day 1 and 3, Z=-2.611, P=0.008; day 5, Z=-2.627, P=0.008;day 7, Z=-2.611, P=0.009; day 14, Z=-2.619, P=0.008, day 21, Z=-2.227, P=0.051.B: day -1, Z=-4.88, P=0.639; day 1, Z=-2.847, P=0.003; day 3 and 5, Z=-2.842, P=0.003; day 7, Z=-2.847, P=0.003;day 14, Z=-2.842, P=0.003; day 21, Z=-2.632, P=0.008. C-D: The effect of microinjection of TNFα or IL-1β into RVM of naïve rats on the level of 5-HT in RVM and spinal dorsal horn。C: 5-HT level in RVM.F(3, 16)=143.4, P<0.001. ***P<0.001, TNFα group compared with vehicle group;***P<0.001, IL-1β group compared with vehicle group。D: 5-HT level in SP.F(3, 16)=29.14, P<0.001. ***P<0.001, TNFα group compared with vehicle ;***P<0.001, IL-1β group compared with vehicle group.

    icon Download:  Full-size image | High-res image | Low-res image

    3 讨 论

    在本研究中,我们发现SMIR可引起大鼠后肢产生持续性痛觉敏感,且RVM中致炎细胞因子TNFα和IL-1β显著上调。此外,将TNFα和IL-1β中和性抗体微量注射入RVM中可防止SMIR引起机械痛敏的产生,并抑制SMIR引起的RVM及脊髓背角5-HT水平的升高。而在正常动物RVM内微量注射TNFα或IL-1β均可引起持续性机械痛敏,并引起RVM及脊髓内5-HT的水平升高。这些结果表明,RVM致炎细胞因子增多通过引起下行性易化作用参与了CPSP。

    transl

    以前的观点认为慢性术后痛主要由手术期间外周神经的损伤产生。然而,研究表明,皮肤/肌肉切开和牵拉(SMIR模型)导致CPSP产生的同时并没有引起外周神经损伤

    2,却引起了作为痛觉信号上行传递必经之路的脊髓背角胶质细胞的激活及致炎细胞因子的释放3。该研究进一步发现作为痛觉调制系统的重要区域——RVM内致炎细胞因子的表达也上调,中和TNFα或IL-1β可以阻断SMIR后持续性疼痛的产生。提示RVM致炎细胞因子上调导致的炎症微环境的出现也参与CPSP的产生。
    transl

    内源性痛觉调制系统主要由中央导水管周围灰质和RVM构成。过度疼痛可激活内源性痛觉调制系统,从而起控制疼痛的作用。RVM内 50% 左右的神经元为 5-HT能神经元,可对伤害性信息传递产生紧张性抑制作用。与急性痛时不同,机体处于病理性疼痛状态时,内源性痛觉调制系统自身发生了显著的变化

    16。最新研究报道:神经损伤引起脊髓背角氯离子失衡,导致内源性5-HT系统由下行抑制转变为下行易化,进而导致神经病理性疼痛17。除此之外,在病理性状态时,脊髓5-HT受体亚型的表达发生了变化。正常状态时脊髓内痛觉初级传入纤维末梢上(即Aδ和C传入 纤维末梢)以5-HT1A受体表达为主,RVM释放的5-HT通过与5-HT1A受体结合,抑制了痛刺激引起的兴奋性神经递质谷氨酸的释放,从而抑制了痛觉信号从脊髓向丘脑的传递。而病理情况下脊髓非选择性配体门控通道5-HT3受体表达上调18],5-HT转而与5-HT3受体结合,对阳离子钠、钾、钙等离子的通透性增加,增加神经末梢递质的释放,从而引起病理性疼痛19。本研究进一步发现SMIR导致RVM和脊髓背角5-HT含量均增多,综合以前的研究报道,我们认为在SMIR后,RVM起源的5-HT介导的下行性易化作用发生了增强,由此介导了慢性术后疼痛的产生。
    transl

    我们的前期工作已经报道SMIR可引起DRG和脊髓背角致炎细胞因子的上调

    37。有研究表明,在DRG, TNFα和IL-1β可上调电压门控钠通道,引起感觉神经元放电增多,也就是产生了外周敏感化20-21。在本研究中,我们发现SMIR 后致炎细胞因子TNFα或IL-1β在RVM中上调。文章报道: TNFɑ通过作用于神经元的TNFR1, 激活PI3K信号通路,特异性引起不包含GluR2 的AMPA受体在细胞膜上表达,同时,TNFɑ也可引起细胞膜上GABAA受体表达降低22。膜片钳记录也显示TNFɑ和IL-1β可引起AMPA- 或 NMDA电流增大及GABA电流减小23。因此,致炎细胞因子TNFα和IL-1β可增强谷氨酸介导的兴奋性突触传递,并可减弱GABA介导的抑制性突触传递。通过分别对兴奋性和抑制性突触发挥长时程的影响,从而驱动神经元过度兴奋 ,进而促进痛觉信号的上行传递。
    transl

    RVM内预防性给予TNFα或IL-1β中和性抗体可缓解机械痛敏并降低RVM和脊髓背角中的5-HT水平。而在正常动物,RVM内注射微量的TNFα或IL-1β可引起机械痛敏,同时RVM和脊髓背角5-HT水平升高。RVM的神经元根据对μ受体激动剂的敏感性分成两类,一类对μ受体激动剂不敏感,而另外一类细胞膜上表达μ受体(MOR)且对μ阿片受体激动剂产生超级化反应,即抑制反应

    24-25 。在正常情况下,阿片类物质部分地通过减少RVM 神经元的GABA信息传递,激活下行抑制系统而产生抑制疼痛的作用。然而在致炎细胞因子TNFɑ或IL-1β存在的情况下,无论是GABA的输入活动还是GABAA受体的性质都会发生改变,导致GABA介导的抑制性突触传递功能受到抑制(去抑制),由此可能进一步激活MOR阳性神经元的神经元26,导致其释放5-HT增多。RVM 5-HT 的释放可通过引起下行性易化作用,最终导致痛觉过敏。这与我们的发现是一致的,即在RVM注射TNFɑ或IL-1β可引起RVM和脊髓背角5-HT浓度的增加。我们目前的实验只是发现了5-HT的增高,如能进一步验证脊髓5-HT受体的表达情况,以及使用5-HT受体激动剂和拮抗剂加以验证,或能测定5-HT代谢物5-羟阴多酰乙酸(5-HIAA)与5-HT比值的改变情况,并将其作为5-HT释放的指标27-28,将能显著提高我们研究的可信性和科学性。这也是该研究的局限之处,后续将会进一步跟进深入研究。
    transl

    既往研究表明,TNFɑ和IL-1β 的受体,即TNFR1和IL-1R, 主要表达在含有NMDAR亚基NR1的RVM 神经元

    8,而TNFR2主要位于胶质细胞上28。最近的研究表明,敲除小胶质细胞的TNFR2可引起淋巴细胞入侵,T细胞激活以及中枢神经脱髓鞘,从而导致自身免疫性脑脊髓炎出现时间提前,说明小胶质细胞的TNFR2具有一定的保护意义。而敲除单核/巨噬细胞的TNFR2 可通过减轻外周T细胞激活及中枢T细胞入侵及脱髓鞘起到减轻自身免疫性脑脊髓炎的作用,提示单核/巨噬细胞的TNFR2具有加重自身免疫性脑脊髓炎的作用29。虽然本研究未评估TNFR1及TNFR2的表达情况及表达的 细胞类型,但据以往的研究,我们可以推测出SMIR后RVM上调的两类炎性因子也可能是通过神经元及非神经元两方面发挥致痛作用。我们的实验结果表明疼痛在术后 1 d即刻诱导,且疼痛行为的进展具有时效性,3 d到峰值,维持至7 d。免疫荧光结果也表明 (图 2),RVM 脑区中 TNFα 和 IL-1β在 1 d和 7 d时表达并无显著差异,表明TNFα 和 IL-1β可能有助于疼痛启动,但似乎仍有其他机制参与疼痛发展。过往研究指出RVM内注射TNFɑ可通过磷酸化NR1受体异化痛觉过敏,SMIR后RVM内升高的TNFɑ可能通过类似的作用机制导致疼痛8。既往研究表明,除了TNFα和IL-1β之外,RVM中的其他介质包括胆囊收缩素30-31和脑源性神经营养因子11也参与了疼痛的易化作用。我们之前的研究也表明,NADPH 氧化酶2 激活导致活性氧簇的释放也起到了类似的作用12]。综上所述,预防慢性术后疼痛的预防不应只关注手术切口本身,而应关注手术所导致的炎症微环境的形成及下行易化系统的激活。
    transl

    参考文献

    1

    Steyaert ADe Kock M. Chronic postsurgical pain[J]. Curr Opin Anaesthesiol2012255):584-588. [Baidu Scholar] 

    2

    Flatters SJ. Characterization of a model of persistent postoperative pain evoked by skin/muscle incision and retraction (SMIR)[J]. Pain20081351-2):119-130. [Baidu Scholar] 

    3

    Ying YLWei XHXu XBet al. Over-expression of P2X7 receptors in spinal glial cells contributes to the development of chronic postsurgical pain induced by skin/muscle incision and retraction (SMIR) in rats[J]. Exp Neurol2014261836-843. [Baidu Scholar] 

    4

    Guo WMiyoshi KDubner Ret al. Spinal 5-HT3 receptors mediate descending facilitation and contribute to behavioral hypersensitivity via a reciprocal neuron-glial signaling cascade[J]. Mol Pain2014910):35. [Baidu Scholar] 

    5

    Cai YQWang WHou YYet al. Optogenetic activation of brainstem serotonergic neurons induces persistent pain sensitization[J]. Mol Pain20141070. [Baidu Scholar] 

    6

    Wang WZhong XLi Yet al. Rostral ventromedial medulla-mediated descending facilitation following P2X7 receptor activation is involved in the development of chronic post-operative pain[J]. J Neurochem20191496):760-780. [Baidu Scholar] 

    7

    Huang ZXLu ZJMa WQet al. Involvement of RVM-expressed P2X7 receptor in bone cancer pain: mechanism of descending facilitation[J]. Pain20141554):783-791. [Baidu Scholar] 

    8

    Wei FGuo WZou Set al. Supraspinal glial-neuronal interactions contribute to descending pain facilitation[J]. J Neurosci20082842):10482-10495. [Baidu Scholar] 

    9

    Guo MChen FGuo JCet al. Study of the hippocampus and the anterior cingulate gyrus by proton MR spectroscopy in patients with post-traumatic stress disorder[J]. Asian Pac J Trop Med201252):162-164. [Baidu Scholar] 

    10

    Roberts JOssipov MHPorreca F. Glial activation in the rostroventromedial medulla promotes descending facilitation to mediate inflammatory hypersensitivity[J]. Eur J Neurosci2009302):229-241. [Baidu Scholar] 

    11

    Guo WRobbins MTWei Fet al. Supraspinal brain-derived neurotrophic factor signaling: a novel mechanism for descending pain facilitation[J]. J Neurosci2006261):126-137. [Baidu Scholar] 

    12

    代娟丽杨涛魏绪红.延髓头端腹内侧部NADPH氧化酶2激活导致活性氧簇释放在皮肤/肌肉切开和牵拉引起的慢性术后疼痛中的作用[J].中国病理生理杂志2021375):769-778. [Baidu Scholar] 

    Dai JLYang TWei XH. NADPH oxidase 2-derived release of reactive oxygen species in rostralventromedial medulla contributes to chronic postoperative pain afterskin/muscle incision and retraction[J]. Chin J Pathophysiol2021375):769-778. [Baidu Scholar] 

    13

    DeLeo JAColburn RWRickman AJ. Cytokine and growth factor immunohistochemical spinal profiles in two animal models of mononeuropathy[J]. Brain Res19977591):50-57. [Baidu Scholar] 

    14

    Wei XHYang TWu Qet al. Peri-sciatic administration of recombinant rat IL-1β induces mechanical allodynia by activation of src-family kinases in spinal microglia in rats[J]. Exp Neurol2012342):389-397. [Baidu Scholar] 

    15

    Wei XHNa XDLiao GJet al. The up-regulation of IL-6 in DRG and spinal dorsal horn contributes to neuropathic pain following L5 ventral root transection[J]. Exp Neurol2013241159-168. [Baidu Scholar] 

    16

    Bardin L. The complex role of serotonin and 5-HT receptors in chronic pain[J]. Behav Pharmacol2011225-6):390-404. [Baidu Scholar] 

    17

    Aby FLorenzo LEGrivet Zet al.Switch of serotonergic descending inhibition into facilitation by a spinal chloride imbalance in neuropathic pain[J]. Sci Adv2022830): eabo0689. [Baidu Scholar] 

    18

    Suzuki RRygh LJDickenson AH. Bad news from the brain: descending 5-HT pathways that control spinal pain processing[J]. Trends Pharmacol Sci20042512):613-617. [Baidu Scholar] 

    19

    Song JYing YWang Wet al. The role of P2X7R/ERK signaling in dorsal root ganglia satellite glial cells in the development of chronic postsurgical pain induced by skin/muscle incision and retraction (SMIR)[J]. Brain Behav Immun201869180-189. [Baidu Scholar] 

    20

    He XHZang YChen Xet al.TNF-α contributes to up-regulation of Nav1.3 and Nav1.8 in DRG neurons following motor fiber injury[J]. Pain20101512):266-279. [Baidu Scholar] 

    21

    Noh MCStemkowski PLSmith PA. Long-term actions of interleukin-1β on K+, Na+ and Ca2+ channel currents in small, IB4-positive dorsal root ganglion neurons; possible relevance to the etiology of neuropathic pain[J]. J Neuroimmunol2019332198-211. [Baidu Scholar] 

    22

    Stellwagen DBeattie ECSeo JYet al. Differential regulation of AMPA receptor and GABA receptor trafficking by tumor necrosis factor-alpha[J]. J Neurosci20052512):3219-3228. [Baidu Scholar] 

    23

    Kawasaki YZhang LCheng JKet al. Cytokine mechanisms of central sensitization: distinct and overlapping role of interleukin-1beta, interleukin-6, and tumor necrosis factor-alpha in regulating synaptic and neuronal activity in the superficial spinal cord[J]. J Neurosci20082820):5189-5194. [Baidu Scholar] 

    24

    Pan ZZTershner SAFields HL. Cellular mechanism for anti-analgesic action of agonists of the kappa-opioid receptor[J]. Nature19973896649):382-385. [Baidu Scholar] 

    25

    Ma JZhang YKalyuzhny AEet al. Emergence of functional delta-opioid receptors induced by long-term treatment with morphine[J]. Mol Pharmacol2006694):1137-1145. [Baidu Scholar] 

    26

    Zhang HDougherty PM. Acute inhibition of signalling phenotype of spinal GABAergic neurons by tumour necrosis factor-alpha[J]. J Physiol2011589Pt 18):4511-4526. [Baidu Scholar] 

    27

    Yoshimoto KWatanabe YTanaka Met al. Serotonin2C receptors in the nucleus accumbens are involved in enhanced alcohol-drinking behavior[J]. Eur J Neurosci2012358):1368-1380. [Baidu Scholar] 

    28

    Fu RMei QShiwalkar Net al. Anxiety during alcohol withdrawal involves 5-HT2C receptors and M-channels in the lateral habenula[J]. Neuropharmacology2020163107863. [Baidu Scholar] 

    29

    Gao HDanzi MCChoi CSet al. Opposing functions of microglial and macrophagic TNFR2 in the pathogenesis of experimental autoimmune encephalomyelitis[J]. Cell Rep2017181):198-212. [Baidu Scholar] 

    30

    Marshall TMHerman DSLargent-Milnes TMet al. Activation of descending pain-facilitatory pathways from the rostral ventromedial medulla by cholecystokinin elicits release of prostaglandin-E₂ in the spinal cord[J]. Pain20121531):86-94. [Baidu Scholar] 

    31

    Xie JYHerman DSStiller COet al. Cholecystokinin in the rostral ventromedial medulla mediates opioid-induced hyperalgesia and antinociceptive tolerance[J]. J Neurosci2005252):409-416. [Baidu Scholar] 

    0

    Views

    7

    Downloads

    0

    CSCD

    Alert me when the article has been cited
    Submit
    Tools
    Download
    Export Citation
    Share
    Add to favorites
    Add to my album

    Related Articles

    No data

    Related Author

    WEI Xuhong

    Related Institution

    Department of Physiology, Zhongshan School of Medicine // Department of Physiology and Pain Research Center Sun Yat-Sen University
    0