Dental Institute, King's College London, Guy's Hospital, Oral Surgery Department, Great Maze Pond, London, UK.
J Clin Neurosci. 2010 Nov;17(11):1476-9. doi: 10.1016/j.jocn.2010.04.005. Epub 2010 Aug 11.
The cannabinoid receptor CB1 is involved in modulation of neuronal hypersensitivity and pain. The aim of this study was to evaluate CB1 receptor levels for the first time in dental pain. A total of 19 patients due for molar extraction were divided into two groups, those with existing dental pain (n=9), and those with no history of pain (n=10). Immunohistochemistry and computer image analysis was used to evaluate CB1-positive nerve fibres in tooth pulp, with neurofilament-immunostaining as a structural nerve marker. CB1-immunoreactive nerve fibres were scattered throughout the tooth pulp and often seen in nerve bundles, but the fibres did not penetrate the subodontoblastic layer. There was no statistically significant change in the CB1 nerve fibre percentage area in the painful group compared to the non-painful group (p=0.146); the neurofilament fibres were significantly reduced in the painful group compared to the controls (p=0.028), but there was no difference in the ratio of CB1 to neurofilaments between the two groups. Thus, CB1 expression is maintained by nerve fibres in painful human dental pulp, and peripherally-restricted CB1 agonists currently in development may advance the treatment of dental pain.
大麻素受体 CB1 参与神经元过敏和疼痛的调节。本研究旨在首次评估牙科疼痛中的 CB1 受体水平。总共 19 名因磨牙拔除而就诊的患者被分为两组，一组有现有的牙科疼痛（n=9），另一组无疼痛史（n=10）。免疫组织化学和计算机图像分析用于评估牙髓中 CB1 阳性神经纤维，以神经丝免疫染色作为结构神经标记。CB1 免疫反应性神经纤维散布在整个牙髓中，常可见于神经束中，但纤维不会穿透牙骨质下层。与无痛组相比，疼痛组的 CB1 神经纤维百分比面积无统计学显著变化（p=0.146）；与对照组相比，疼痛组的神经丝纤维明显减少（p=0.028），但两组之间 CB1 与神经丝的比值无差异。因此，疼痛人牙髓中的神经纤维维持 CB1 的表达，目前正在开发的外周受限 CB1 激动剂可能会推进牙科疼痛的治疗。
