三叉神经节酸敏感离子通道ASIC3对大鼠牙移动疼痛的调控机制

Dentofacial anomaly, highly prevalent in populations, severely influences patients’ health. Thus, orthodontic treatment plays an important role in improving people’s health. However, pain induced by tooth movement interferes with the applications of orthodontic treatment. It is paramount to delve into the mechanisms underlying pain induced by tooth movement and to explore effective analgesic treatment. Research advances reveal that acid sensing ion channel 3 (ASIC3) participate in the regulations of inflammatory pain. Pain induced by tooth movement is an inflammatory pain in the orofacial region, but whether ASIC3 participate in pain induced by tooth movement are still largely unknown. Based on our previous results and recent understanding, we propose that trigeminal ASIC3 could regulate pain induced by tooth movement through increasing neuronal excitability and elevating periodontal sensitivity to stimuli. Through virus transduction, RNA interference, gene therapy, electrophysiology and molecular biology, this project aims to unravel the two proposed mechanisms—neuronal and periodontal mechanism—whereby trigeminal ASIC3 regulates pain induced by tooth movement in rats. Furthermore, this project aims to determine the effectiveness of ASIC3-based-gene-therapy on alleviating pain induced by tooth movement in rats and to provide scientific basis for analgesic treatment for orthodontic patients.

牙颌畸形发病率高并严重影响患者身心健康。因此，正畸治疗对提高人口健康水平具有十分重要的意义。然而，正畸治疗引起的牙移动疼痛严重影响正畸治疗的开展。深入研究牙移动疼痛机制并探索有效的镇痛方法已成为优化正畸治疗的关键。研究表明酸敏感离子通道3型（ASIC3）在炎性疼痛调控中扮演重要角色。牙移动疼痛是一种颌面部的炎性疼痛，但ASIC3是否参与牙移动疼痛调控尚未明确。基于前期工作基础和已有的研究，我们猜想：牙移动后大鼠三叉神经节ASIC3通过提高神经元兴奋性和提高牙周膜神经末梢对疼痛刺激的敏感度两种机制调控牙移动疼痛。本项目运用病毒转染、RNA干扰技术、基因治疗、组织和细胞电生理学技术和分子生物学技术等，旨在阐明三叉神经节ASIC3调控大鼠牙移动疼痛的神经元途径机制和牙周膜途径机制。另外，本项目探索基于ASIC3的基因治疗缓解大鼠牙移动疼痛的可行性，为今后研发适用于正畸患者的镇痛措施提供科学依据。

酸敏感离子通道3型（ASIC3）在炎性疼痛调控中扮演重要角色。牙移动疼痛是一种颌面部的炎性疼痛，但ASIC3是否参与牙移动疼痛调控尚未明确。本项目通过病毒转染、RNA干扰、基因治疗和分子生物学等技术完成检测大鼠牙移动后牙周膜ASIC3表达水平、检测大鼠牙移动后三叉神经节ASIC3表达水平、原代培养三叉神经节神经元、构建慢病毒载体lenti-ASIC3、大鼠体内转染慢病毒载体lenti-ASIC3等研究内容。本项目证实了ASIC3主要通过三叉神经节神经元合成并运输ASIC3至牙周膜途径调控大鼠牙移动疼痛。重要实验结果和关键数据如下：.1..证实牙周ASIC3在大鼠牙移动疼痛中扮演重要角色：大鼠牙移动后牙周膜ASIC3表达上调；我们通过大鼠面部表情分析评估大鼠牙移动疼痛水平，结果表明大鼠牙移动疼痛的变化趋势与牙周ASIC3表达水平相似；牙周注射ASCI3受体特异性抑制剂APETx2和非特异性抑制剂amiloride能缓解大鼠牙移动疼痛。.2..证实ASIC3参与大鼠牙齿机械压力感受：ASIC3受体表达在牙周机械感受器Ruffini小体；大鼠牙周膜注射ASIC3拮抗剂后咬合力增加疼痛减小，ASIC3表达下调；注射ASIC3激动剂咬合力下降疼痛增加，ASIC3表达上调。.3..证实三叉神经节ASIC3通过运输至牙周膜参与大鼠牙移动疼痛的调控：我们通过对大鼠牙移动后三叉神经节检测，发现实验组大鼠三叉神经节神经元ASIC3表达上调；大鼠三叉神经节注射ASIC3拮抗剂后咬合力增加疼痛下降，牙周膜ASIC3表达下调；大鼠三叉神经节注射ASIC3激动剂后咬合力下降疼痛增加，牙周膜ASIC3表达上调。.4..成功构建lenti-ASIC3病毒载体并成功转染大鼠三叉神经节神经元，该病毒载体可成功下调ASIC3表达，并发现可调控CGRP和TRPV1受体：本课题组已成功制备能下调ASIC3的慢病毒载体，靶向转染至大鼠三叉神经节并成功转染。大鼠三叉神经节ASIC3下调后，CGRP和TRPV1表达下调。.5..本课题组成功开发大鼠三叉神经节病毒转染注射技术和一种用于大鼠牙移动机械敏感性的疼痛评估方法。.. 本课题成果为深入阐明牙移动疼痛的调控机制提供一定的理论依据，并为该领域增添两项新研究技术，为本课题组深入研究牙移动疼痛机制奠定前期基础。