Département de Neurosciences, UMR 6149 Neurosciences Intégratives et Adaptatives, Université de Provence/CNRS-Pôle 3C (Comportement, Cerveau, Cognition), Centre de Saint Charles, Marseille, France.
PLoS One. 2011;6(8):e22262. doi: 10.1371/journal.pone.0022262. Epub 2011 Aug 11.
Functional and reactive neurogenesis and astrogenesis are observed in deafferented vestibular nuclei after unilateral vestibular nerve section in adult cats. The newborn cells survive up to one month and contribute actively to the successful recovery of posturo-locomotor functions. This study investigates whether the nature of vestibular deafferentation has an incidence on the neurogenic potential of the vestibular nuclei, and on the time course of behavioural recovery. Three animal models that mimic different vestibular pathologies were used: unilateral and permanent suppression of vestibular input by unilateral vestibular neurectomy (UVN), or by unilateral labyrinthectomy (UL, the mechanical destruction of peripheral vestibular receptors), or unilateral and reversible blockade of vestibular nerve input using tetrodotoxin (TTX). Neurogenesis and astrogenesis were revealed in the vestibular nuclei using bromodeoxyuridine (BrdU) as a newborn cell marker, while glial fibrillary acidic protein (GFAP) and glutamate decarboxylase 67 (GAD67) were used to identify astrocytes and GABAergic neurons, respectively. Spontaneous nystagmus and posturo-locomotor tests (static and dynamic balance performance) were carried out to quantify the behavioural recovery process. Results showed that the nature of vestibular loss determined the cellular plastic events occurring in the vestibular nuclei and affected the time course of behavioural recovery. Interestingly, the deafferented vestibular nuclei express neurogenic potential after acute and total vestibular loss only (UVN), while non-structural plastic processes are involved when the vestibular deafferentation is less drastic (UL, TTX). This is the first experimental evidence that the vestibular complex in the brainstem can become neurogenic under specific injury. These new data are of interest for understanding the factors favouring the expression of functional neurogenesis in adult mammals in a brain repair perspective, and are of clinical relevance in vestibular pathology.
去传入的前庭核在成年猫单侧前庭神经切断后观察到功能性和反应性神经发生和星形胶质细胞发生。新生细胞存活长达一个月，并积极有助于姿势-运动功能的成功恢复。本研究调查了前庭去传入的性质是否对前庭核的神经发生潜力以及行为恢复的时间进程有影响。使用了三种模拟不同前庭病变的动物模型：单侧且永久性抑制前庭传入的单侧前庭神经切断术（UVN），或单侧迷路切除术（UL，外周前庭感受器的机械破坏），或单侧且可逆性阻断前庭神经传入的四氢生物蝶呤（TTX）。使用溴脱氧尿苷（BrdU）作为新生细胞标志物来揭示前庭核中的神经发生和星形胶质细胞发生，同时使用胶质纤维酸性蛋白（GFAP）和谷氨酸脱羧酶 67（GAD67）分别识别星形胶质细胞和 GABA 能神经元。进行自发性眼球震颤和姿势-运动测试（静态和动态平衡性能）以量化行为恢复过程。结果表明，前庭丧失的性质决定了前庭核中发生的细胞可塑性事件，并影响了行为恢复的时间进程。有趣的是，急性和完全前庭丧失后仅去传入的前庭核表达神经发生潜力（UVN），而当前庭去传入不太严重时（UL，TTX）涉及非结构性可塑性过程。这是第一个实验证据表明，脑干中的前庭复合体在特定损伤下可以具有神经发生能力。这些新数据对于理解在脑修复视角下促进成年哺乳动物功能性神经发生表达的因素具有重要意义，并且在前庭病理学中具有临床意义。
