Neural organization of vertical saccadic eye movement

垂直扫视眼运动的神经组织

基本信息

批准号：
08458267
负责人：
SHINODA Yoshikazu
金额：
$ 4.42万
依托单位：
Tokyo Medical and Dental University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1996
资助国家：
日本
起止时间：
1996 至 1997
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08458267/
关键词：
saccade ocular motoneuron biocytin PPRF HRP superior colliculus eye movement neurophysiology

项目摘要

To understand the neural mechanisms of saccadic eye movement generation, the neural organization from the superior colliculuc (SC) to ocular motoneurons in the horizontal oculomotor system was analyzed in the anesthetized cat. Intracellular responses to stimulation ot the SC were analyzed in abducens motoneurons, medial rectus motoneurons and internuclear neurons (INNs) in the abducens nucleus. Abducens motoneurons received disynaptic excitatory inputs from the contralataeral SC via the ipsilateral paramedian pontine reticular formation (PPRF) and disynaptic inhibitory inputs from the ipsilateral SC via the contralateral PPRF.These electrophysiological findings were confirmed by anatomical experiments. Last-order premotor neurons were labeled transneuronally after injecting WGA-HRP into the abducens nerve, and in the same preparations dextran-biotin injection into the SC labeled axon terminals of tectoreticular neurons orthgradely in the contralateral PPRF rostral and caudal to the abducens nucleus. These axon terminals of tectoreticular fibers made direct contacts with last-order premotor neurons terminating on ipsilateral abducens motoneurons and contralateral abducens motoneurons. INNs in the abducens nucleus received disynaptic excitatory inputs from the contralateral SC and disynaptic inhibitory inputs from the ipsilateral SC.This pattern was the same as in abducens motoneurons. Medial rectus motoneurons received trisynaptic excitatory inputs from the ipsilateral SC via the contralateral INNs. Two groups of tectoreticular neurons were identified to convey output from the SC to the PPRF.One group projected to the PPRF,but not to the spinal cord, and the other group projected to both the PPRF and the spinal cord.

为了了解saccadic眼动运动产生的神经机制，在麻醉猫中分析了从上胶囊（SC）到水平眼动物系统中的眼动神经元的神经组织。在外表的运动神经元，内侧直肠运动神经元和核外神经元（INNS）中分析了对SC的细胞内反应。卧外的运动神经元通过同侧paramedian pontine网状结构（PPRF）从相反SC中获得了非触觉兴奋性输入，并通过对侧PPRF进行了同侧PPRF。将WGA-HRP注射到外纤维神经后，并在同一制剂中将右侧神经元注射到tectorulocular神经元的SC轴突末端，在相对pprf rostral和caudal to apducens us中。这些tectorencular纤维的轴突末端与终止在同侧外侧的运动神经元和对侧外侧仿生运动神经元的最后阶段前神经元直接接触。外围核中的Inns从对侧SC和双侧抑制性输入中收到了非接触性兴奋性输入，来自同侧SC。此模式与外皮运动神经元相同。内侧直肠运动神经元通过对侧旅馆从同侧SC接收了三突触兴奋性输入。确定了两组tecorenticular神经元，以将其从SC传达到PPRF的pPRF。投影到PPRF，但不能传达给脊髓，而另一组则投影到PPRF和脊髓。