Isu N, Yokota J
Exp Brain Res. 1983;53(1):151-62. doi: 10.1007/BF00239407.
(1) Spikes of single neurons were extracellularly recorded in the medial vestibular nucleus (MVN) in decerebrate cats and were functionally identified as secondary type I neurons by observing their responses to horizontal rotation and monosynaptic activation after stimulation of the ipsilateral vestibular nerve. Axonal projection of these neurons was examined by their antidromic responses to stimulation of the contralateral abducens nucleus, the spinal cord, and the ascending and descending MLF. (2) Almost all secondary type I vestibular neurons which sent their axon to the contralateral abducens nucleus were antidromically activated from the descending MLF at the level of the obex as well. Nearly half of these neurons sent their collateral axon to the level of C1 segment in the spinal cord and approximately one third to the ascending MLF close to the oculomotor complex. (3) The mean conduction velocity was 29 m/s for descending collateral axons and 30 m/s for ascending collateral axons. (4) Systematic tracking for antidromic microstimulation in the contralateral abducens nucleus and spinal gray matter at C2-C3 suggested that collateral axons of single type I vestibular neurons gave off local branches in the abducens nucleus and the motoneuron pool in the upper cervical gray matter. Existence of terminal branches in the neck motoneuron pool was confirmed by intraaxonal staining with horseradish peroxidase (HRP). (5) Neurons which projected to both the contralateral abducens nucleus and the spinal cord were located in a fairly localized region in the ventrolateral part of the rostral MVN. Neurons which projected to the contralateral abducens nucleus and not to the spinal cord were located in a rostrocaudally wider area in the ventrolateral MVN. Neurons projecting to the spinal cord and not to the contralateral abducens nucleus were located in the widest area in the rostrocaudal direction, covering almost the whole extent of the rostral half of the MVN.
(1) 在去大脑猫的内侧前庭核（MVN）中细胞外记录单个神经元的锋电位，并通过观察其对水平旋转的反应以及同侧前庭神经刺激后的单突触激活，将其功能鉴定为II型次级神经元。通过对这些神经元对同侧展神经核、脊髓以及上升和下降的内侧纵束（MLF）刺激的逆向反应来检查其轴突投射。(2) 几乎所有将轴突发送到同侧展神经核的II型次级前庭神经元也能从闩平面水平的下降MLF被逆向激活。这些神经元中近一半将其侧支轴突发送到脊髓C1节段水平，约三分之一发送到靠近动眼神经复合体的上升MLF。(3) 下降侧支轴突的平均传导速度为29 m/s，上升侧支轴突的平均传导速度为30 m/s。(4) 对同侧展神经核和C2 - C3脊髓灰质中逆向微刺激的系统追踪表明，单个I型前庭神经元的侧支轴突在展神经核和上颈段灰质的运动神经元池中发出局部分支。用辣根过氧化物酶（HRP）进行轴内染色证实了颈运动神经元池中有终末分支。(5) 投射到同侧展神经核和脊髓的神经元位于吻侧MVN腹外侧部分的一个相当局限的区域。投射到同侧展神经核但不投射到脊髓的神经元位于腹外侧MVN中前后更宽的区域。投射到脊髓但不投射到同侧展神经核的神经元位于前后方向最宽的区域，几乎覆盖了MVN吻侧一半的整个范围。
