神经性异常性疼痛涉及大鼠脊髓中神经纤连蛋白-1β依赖性神经连接蛋白-1/突触后致密蛋白-95/NR2B级联反应。

Neuropathic Allodynia Involves Spinal Neurexin-1β-dependent Neuroligin-1/Postsynaptic Density-95/NR2B Cascade in Rats.

作者信息

Lin Tzer-Bin, Lai Cheng-Yuan, Hsieh Ming-Chun, Jiang Jian-Lin, Cheng Jen-Kun, Chau Yat-Pang, Ruan Ting, Chen Gin-Den, Peng Hsien-Yu

机构信息

From the Department of Physiology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan (T.-B.L.); Graduate Institute of Basic Medical Science, College of Medicine, China Medical University, Taichung, Taiwan (T.-B.L.); Department of Biotechnology, Asia University, Taichung, Taiwan (T.-B.L.); Department of Medicine, Mackay Medical College, New Taipei, Taiwan (C.-Y.L., M.-C.H., J.-L.J., J.-K.C., Y.-P.C., H.-Y.P.); Department of Veterinary Medicine, College of Veterinary Medicine, National Chung-Hsing University, Taichung, Taiwan (C.-Y.L.); Department of Physiology, School of Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan (M.-C.H.); Department of Anesthesiology, Mackay Memorial Hospital, New Taipei, Taiwan (J.-K.C.); School of Medicine, Fu-Jen Catholic University, New Taipei, Taiwan (T.R.); and Department of Obstetrics and Gynecology, Chung-Shan Medical University Hospital, Chung-Shan Medical University, Taichung, Taiwan (G.-D.C.).

出版信息

Anesthesiology. 2015 Oct;123(4):909-26. doi: 10.1097/ALN.0000000000000809.

DOI:10.1097/ALN.0000000000000809

PMID:26263430

Abstract

BACKGROUND

Neuroligin-1 (NL1) forms a complex with the presynaptic neurexin-1β (Nrx1b), regulating clustering of N-methyl-D-aspartate receptors with postsynaptic density-95 (PSD-95) to underlie learning-/memory-associated plasticity. Pain-related spinal neuroplasticity shares several common features with learning-/memory-associated plasticity. The authors thereby investigated the potential involvement of NL1-related mechanism in spinal nerve ligation (SNL)-associated allodynia.

METHODS

In 626 adult male Sprague-Dawley rats, the withdrawal threshold and NL1, PSD-95, phosphorylated NR2B (pNR2B) expressions, interactions, and locations in dorsal horn (L4 to L5) were compared between the sham operation and SNL groups. A recombinant Nrx1b Fc chimera (Nrx1b Fc, 10 μg, 10 μl, i.t., bolus), antisense small-interfering RNA targeting to NL1 (10 μg, 10 μl, i.t., daily for 4 days), or NR2B antagonist (Ro 25-6981; 1 μM, 10 μl, i.t., bolus) were administered to SNL animals to elucidate possible cascades involved.

RESULTS

SNL-induced allodynia failed to affect NL1 or PSD-95 expression. However, pNR2B expression (mean ± SD from 13.1 ± 2.87 to 23.1 ± 2.52, n = 6) and coexpression of NL1-PSD-95, pNR2B-PSD-95, and NL1-total NR2B were enhanced by SNL (from 10.7 ± 2.27 to 22.2 ± 3.94, 11.5 ± 2.15 to 23.8 ± 3.32, and 8.9 ± 1.83 to 14.9 ± 2.27 at day 7, n = 6). Furthermore, neuron-localized pNR2B PSD-95-pNR2B double-labeled and NL1/PSD-95/pNR2B triple-labeled immunofluorescence in the ipsilateral dorsal horn was all prevented by Nrx1b Fc and NL1-targeted small-interfering RNA designed to block and prevent NL1 expression. Without affecting NL1-PSD-95 coupling, Ro 25-6981 decreased the SNL-induced PSD-95-pNR2B coprecipitation (from 18.7 ± 1.80 to 14.7 ± 2.36 at day 7, n = 6).

CONCLUSION

SNL-induced allodynia, which is mediated by the spinal NL1/PSD-95/pNR2B cascade, can be prevented by blockade of transsynaptic Nrx1b-NL1 interactions.

摘要

背景

神经连接蛋白-1（NL1）与突触前神经配蛋白-1β（Nrx1b）形成复合物，调节N-甲基-D-天冬氨酸受体与突触后致密蛋白95（PSD-95）的聚集，从而成为学习/记忆相关可塑性的基础。疼痛相关的脊髓神经可塑性与学习/记忆相关可塑性具有一些共同特征。因此，作者研究了NL1相关机制在脊髓神经结扎（SNL）相关的异常性疼痛中的潜在作用。

方法

在626只成年雄性Sprague-Dawley大鼠中，比较假手术组和SNL组之间的撤药阈值以及NL1、PSD-95、磷酸化NR2B（pNR2B）在背角（L4至L5）中的表达、相互作用和定位。将重组Nrx1b Fc嵌合体（Nrx1b Fc，10μg，10μl，鞘内注射，推注）、靶向NL1的反义小干扰RNA（10μg，10μl，鞘内注射，每日一次，共4天）或NR2B拮抗剂（Ro 25-6981；1μM，10μl，鞘内注射，推注）给予SNL动物，以阐明可能涉及的级联反应。

结果

SNL诱导的异常性疼痛未影响NL1或PSD-95的表达。然而，SNL增强了pNR2B的表达（平均值±标准差，从13.1±2.87增至23.1±2.52，n = 6）以及NL1-PSD-95、pNR2B-PSD-95和NL1-总NR2B的共表达（第7天时从10.7±2.27增至22.2±3.94、从11.5±2.15增至23.8±3.32、从8.9±1.83增至14.9±2.27，n = 6）。此外，Nrx1b Fc和旨在阻断和防止NL1表达的靶向NL1的小干扰RNA可防止同侧背角中神经元定位的pNR2B、PSD-95-pNR2B双标记以及NL1/PSD-95/pNR2B三标记免疫荧光。Ro 25-6981在不影响NL1-PSD-95偶联的情况下，减少了SNL诱导的PSD-95-pNR2B共沉淀（第7天时从18.7±1.80降至14.7±2.36，n = 6）。