在三叉神经病理性疼痛大鼠模型中,面部感觉运动皮层会发生神经可塑性变化。
Face sensorimotor cortex undergoes neuroplastic changes in a rat model of trigeminal neuropathic pain.
作者信息
Yao Dongyuan, Sessle Barry J
机构信息
School of Pharmaceutical Science and Jiangxi Mental Hospital, Nanchang University, 461 Bayi Road, Nanchang, 330006, Jiangxi, China.
Department of Physiology, Faculty of Dentistry, and Faculty of Medicine, University of Toronto, 124 Edward St., Toronto, ON, M5G 1G6, Canada.
出版信息
Exp Brain Res. 2018 May;236(5):1357-1368. doi: 10.1007/s00221-018-5226-2. Epub 2018 Mar 8.
Trigeminal nerve injury can result in neuropathic pain behavior and alterations in motor function, but it is unclear if such injury produces neuroplastic alterations in face sensorimotor cortex that could contribute to the alterations in motor function. Therefore, this study aimed to determine if trigeminal nerve injury in a rat neuropathic pain model induces neuroplastic changes in jaw and tongue motor representations in face sensorimotor cortex in association with facial nociceptive behavior. Right infraorbital nerve transection was performed in adult male Sprague-Dawley rats; sham-operated rats served as controls. Nociceptive behavior was assessed by testing facial mechanical sensitivity pre-operatively and post-operatively (1-28 days). Intracortical microstimulation was also applied post-operatively in a series of microelectrode penetrations to map jaw and tongue motor representations in the face sensorimotor cortex by analyzing anterior digastric and genioglossus electromyographic activities evoked by microstimulation at histologically verified sites in face primary somatosensory cortex (face-SI) as well as face primary motor cortex (face-MI). Compared to sham, infraorbital nerve injury induced a significant (2-way repeated-measures analysis of variance, P < 0.001) bilateral decrease in facial mechanical threshold that lasted up to 28 days post-operatively. Nerve injury also induced a significant bilateral decrease compared to sham (P < 0.05) in the number of anterior digastric and/or genioglossus sites in face-MI and in face-SI. These findings indicate that trigeminal nerve injury induces neuroplastic alterations in jaw and tongue motor representations in face sensorimotor cortex that are associated with facial nociceptive behavior and that may contribute to sensorimotor changes following trigeminal nerve injury.
三叉神经损伤可导致神经性疼痛行为和运动功能改变,但尚不清楚这种损伤是否会在面部感觉运动皮层产生神经可塑性改变,而这种改变可能导致运动功能改变。因此,本研究旨在确定大鼠神经性疼痛模型中的三叉神经损伤是否会在面部感觉运动皮层的颌骨和舌部运动表征中诱导神经可塑性变化,并与面部伤害感受行为相关联。对成年雄性Sprague-Dawley大鼠进行右侧眶下神经横断术;假手术大鼠作为对照。术前和术后(1 - 28天)通过测试面部机械敏感性来评估伤害感受行为。术后还通过一系列微电极穿刺进行皮层内微刺激,通过分析在面部初级体感皮层(面部SI)以及面部初级运动皮层(面部MI)经组织学验证的部位进行微刺激所诱发的前腹侧二腹肌和颏舌肌肌电图活动,来绘制面部感觉运动皮层中的颌骨和舌部运动表征。与假手术组相比,眶下神经损伤导致面部机械阈值显著(双向重复测量方差分析,P < 0.001)双侧降低,持续至术后28天。与假手术组相比,神经损伤还导致面部MI和面部SI中前腹侧二腹肌和/或颏舌肌部位的数量显著双侧减少(P < 0.05)。这些发现表明,三叉神经损伤会在面部感觉运动皮层的颌骨和舌部运动表征中诱导神经可塑性变化,这些变化与面部伤害感受行为相关,并且可能导致三叉神经损伤后的感觉运动变化。