Diagne Monique, Valla Jocelyne, Delfini Christian, Buisseret-Delmas Catherine, Buisseret Pierre
Laboratoire de Neuroanatomie Fonctionnelle des Systèmes Sensorimoteurs, Paris, France.
J Comp Neurol. 2006 Jun 20;496(6):759-72. doi: 10.1002/cne.20964.
This study identified neurons in the sensory trigeminal complex with connections to the medial (MVN), inferior (IVN), lateral (LVN), and superior (SVN) vestibular nuclei or the spinal cord. Trigeminovestibular and trigeminospinal neurons were localized by injection of retrograde tracers. Immunohistochemical processing revealed gamma-aminobutyric acid (GABA)- and glutamate-containing neurons in these two populations. Trigeminovestibular neurons projecting to the MVN and the IVN were in the caudal principal nucleus (5P), pars oralis (5o), interpolaris (5i), and caudalis (5c) and scattered throughout the rostral 5P. Projections were bilateral to the IVN, with an ipsilateral dominance to the MVN, except from the rostral 5P, which was contralateral. Neurons projecting to the LVN were numerous in the ventral caudal 5P and the 5o and less abundant in the rostral 5P, 5i, and 5c. Our results suggested that only 5P and 5o project to the dorsal LVN. Neurons projecting to the SVN were in the dorsal 5P, 5o, and 5i but not in 5c. Trigeminospinal neurons were mainly in the ventral 5o and 5i and in the lateral 5c, rarely or never in 5P. Among trigeminovestibular neurons, most of the somas were immunoreactive for glutamate, but some reacted for GABA. Among trigeminospinal neurons, the number of somas immunoreactive for each of the two amino acids was similar. Trigeminal terminals were observed in contact with vestibulospinal neurons in the IVN and LVN, giving evidence of a trigeminovestibulospinal pathway. Therefore, inhibitory and excitatory facial inputs may contribute through trigeminospinal or trigeminovestibulospinal pathways to the control of head/neck movements.
本研究确定了感觉三叉神经复合体中与内侧（MVN）、下侧（IVN）、外侧（LVN）和上侧（SVN）前庭核或脊髓有连接的神经元。通过注射逆行示踪剂对三叉神经前庭和三叉神经脊髓神经元进行定位。免疫组织化学处理揭示了这两类神经元中含γ-氨基丁酸（GABA）和谷氨酸的神经元。投射到MVN和IVN的三叉神经前庭神经元位于尾侧主核（5P）、口部（5o）、极间部（5i）和尾部（5c），并散布于头侧5P。投射至IVN是双侧性的，除了头侧5P是对侧投射外，对MVN的投射以同侧为主。投射至LVN的神经元在尾侧腹侧5P和5o中数量众多，而在头侧5P、5i和5c中数量较少。我们的结果表明，只有5P和5o投射至背侧LVN。投射至SVN的神经元位于背侧5P、5o和5i，但不在5c中。三叉神经脊髓神经元主要位于腹侧5o和5i以及外侧5c，很少或从未见于5P。在三叉神经前庭神经元中，大多数胞体对谷氨酸呈免疫反应，但有些对GABA呈反应。在三叉神经脊髓神经元中，对这两种氨基酸呈免疫反应的胞体数量相似。在IVN和LVN中观察到三叉神经终末与前庭脊髓神经元相接触，这证明了三叉神经前庭脊髓通路的存在。因此，抑制性和兴奋性面部输入可能通过三叉神经脊髓或三叉神经前庭脊髓通路对头/颈部运动的控制起作用。
