摘要
本文作者在三叉神经本体感觉的中枢通路的研究中,曾注意到一条由三级神经元构成的通路。为了证实此通路,本研究用Ricin跨节溃变与HRP逆行追踪相结合的方法在光、电镜水平进行了研究。将Ricin注入大鼠咬肌神经,造成三叉神经中脑核神经元及其中枢突的溃变,再将HRP注入对侧丘脑腹后内侧核,逆行标记感觉主核背内侧部和三叉上核尾外侧部的三叉—丘脑投射神经元。在光镜下观察到明确的中脑核神经元及其终末溃变象以及感觉主核和三叉上核尾外侧部的HRP逆标细胞;在电镜下观察到中脑核神经元的溃变终末与后二者的丘脑投射神经元的胞体和树突形成轴-体和轴-树突触。从而确证了脑内存在一条由中脑核初级传入神经元,感觉主核背内侧部、三叉上核尾外侧部第二级中继神经元和丘脑腹后内侧核第三级神经元组成的三级通路。本文还对感觉主核背内侧部和三叉上核尾外侧部在三叉神经本体感觉中枢通路中的地位,以及本文证明的三级通路与王百忍等发现的四级通路的并存及其相互关系做了较深入的讨论。
The proprioceptive pathway of the fifth nerve in the CNS is not yet known at all. The authors have suggested a "three-neuron pathway" model of the proprioceptive information from the trigeminal mesencephalic nucleus (Vme) to the cortex on the basis of our previous studies. In order to confirm this suggestion, the present study was made on the light and electron microscopic level by using the methods of ricin transganglionic degeneration combined with HRP retrograde tracing. The degeneration of the Vme and HRP labeling of neurons projecting to the thalamus in the dorsomedial part of trigeminal principal sensory nucleus (Vpdm) and caudolateral part of supratrigeminal nucleus (Vsup CL) were observed respectively after riein injection into masseteric nerve and HRP injection into ventral posteromedial nucleus of thalamus contralaterally. Under electron microscope, it was observed that axo-somatic and axodendritic synapses occurred between the degenerated terminals of the Vme neurons and the thalamic projecting neurons in the Vpdm and Vsup CL neuropil. These findings established a "three-neuron proprioceptive pathway" from the fifth nerve to the cerebral cortex in the CNS, in which Vpdm and Vsup CL are proved to be the relay stations of the second neuron.
出处
《神经解剖学杂志》
CSCD
北大核心
1992年第1期57-62,共6页
Chinese Journal of Neuroanatomy
基金
国家自然科学基金
关键词
三叉神经
本体感觉
三级中枢通路
proprioception of the fifth nerve
three-neuron pathway
synaptic connection
rat
