Jian B J, Shintani T, Emanuel B A, Yates B J
Department of Otolaryngology, University of Pittsburgh, Eye and Ear Institute, Room 106, 203 Lothrop Street, Pittsburgh, PA 15213, USA.
Exp Brain Res. 2002 May;144(2):247-57. doi: 10.1007/s00221-002-1042-8. Epub 2002 Mar 5.
The major goal of this study was to determine the patterns of convergence of non-labyrinthine inputs from the limbs and viscera onto vestibular nucleus neurons receiving signals from vertical semicircular canals or otolith organs. A secondary aim was to ascertain whether the effects of non-labyrinthine inputs on the activity of vestibular nucleus neurons is affected by bilateral peripheral vestibular lesions. The majority (72%) of vestibular nucleus neurons in labyrinth-intact animals whose firing was modulated by vertical rotations responded to electrical stimulation of limb and/or visceral nerves. The activity of even more vestibular nucleus neurons (93%) was affected by limb or visceral nerve stimulation in chronically labyrinthectomized preparations. Some neurons received non-labyrinthine inputs from a variety of peripheral sources, including antagonist muscles acting at the same joint, whereas others received inputs from more limited sources. There was no apparent relationship between the spatial and dynamic properties of a neuron's responses to tilts in vertical planes and the non-labyrinthine inputs that it received. These data suggest that non-labyrinthine inputs elicited during movement will modulate the processing of information by the central vestibular system, and may contribute to the recovery of spontaneous activity of vestibular nucleus neurons following peripheral vestibular lesions. Furthermore, some vestibular nucleus neurons with non-labyrinthine inputs may be activated only during particular behaviors that elicit a specific combination of limb and visceral inputs.
本研究的主要目标是确定来自四肢和内脏的非迷路性输入汇聚到接收来自垂直半规管或耳石器官信号的前庭核神经元上的模式。次要目的是确定非迷路性输入对前庭核神经元活动的影响是否受双侧外周前庭损伤的影响。在未损毁迷路的动物中，其放电受垂直旋转调制的前庭核神经元大多数（72%）对肢体和/或内脏神经的电刺激有反应。在长期迷路切除的标本中，更多的前庭核神经元（93%）的活动受肢体或内脏神经刺激的影响。一些神经元从多种外周来源接收非迷路性输入，包括作用于同一关节的拮抗肌，而其他神经元则从更有限的来源接收输入。神经元对垂直平面倾斜的反应的空间和动态特性与其所接收的非迷路性输入之间没有明显关系。这些数据表明，运动过程中引发的非迷路性输入将调节中枢前庭系统的信息处理，并可能有助于外周前庭损伤后前庭核神经元自发活动的恢复。此外，一些具有非迷路性输入的前庭核神经元可能仅在引发特定肢体和内脏输入组合的特定行为期间被激活。
