ラットの外側頚核

Abstract

It has been established that the lateral cervical nucleus (LCN) in the cat is located in the first two cervical segments (C1 and C2).But in the rat even the existence of the LCN is stillcontroversial. In the present investigation, the entire cervical segments were sectioned seriallyand stained with cresyl violet in order to study the morphological characteristics of individualnerve cells.The projections to and from these nerve cells were then studied by employing the Nauta method and the HRP technique.Groups of nerve cells were found in the region ventral tothe dorsal horn in the lateral funiculus in each cervical segment.They were especially prominentat the levels of C1 and C2.These nerve cells received fibers ascending in the spinal cordhomolaterally and projected their axons into the brain stem contralaterally.These findings indicatedthat the groups of the nerve cells in C1 and C2 in the rat corresponded to the nerve cells inthe LCN in the cat.Furthermore, in the rat the nerve cells coinciding in the morphologicalcharacteristics with those in the LCN were found also in other cervical segments.