Anatomical and Physiological studies of the laryngeal feedback system and it's control.

本研究利用逆行神经示踪剂对歧义核的树突进行了实验，结果表明歧义核中支配喉内肌的神经元和吻侧与呼吸系统有关的botzinger神经元与尾侧歧义核中的神经元之间存在密切的相互关系。伴吞咽旋转的咽部运动神经元的树突面积和密度与歧义核其他神经元的树突弧度和密度不同。这表明吞咽系统是复杂的。本研究还通过fos免疫组化检测了猫脑干下部的部分功能性神经元通路，并通过免疫组化双染色技术鉴定了哪些区域含有兴奋性或抑制性中间神经元。本研究结果与孤立核（NTS）和双核（NA）之间的网状结构（FTL）的外侧节段场的Fos阳性神经元是声门关闭反应的中间神经元的假设一致。在猫喉诱发反应实验中，认为P3-N3-P4来源于网状结构的外侧节段野神经元。从潜伏期来看，NTS和NA之间存在少量中间神经元。通过对GABA和谷氨酸的免疫组化，推测喉反射通路包括兴奋性和抑制性内神经元。可以推测，痉挛性发声障碍的原因之一是抑制通路的紊乱。

In this study, the experiments of the dendrites of the nucleus ambiguus using retrograde neurotracer suggested the intimate interrelation between the neurons in the nucleus ambiguus which supply the intrinsic laryngeal muscles and Botzainger neurons relating with the respiratory system in the rostral Part, and the neurons in the retroambigual nucleus in the caudal part. The area and density of the dcntritcs of the pharyngcal motoncurons rclating with swallowing were different from the arca and density of the dendrites of the other neurons in the nucleus ambiguus. This result showed the swallowing system was complex. This study also detecrmined that part of the functional neuronal Pathway within the lower brainstem in the cat by means of Fos-immunohistochemistry and identified which regions contain excitatory or inhibitory interneurons using double staining immunohistochemical techniques. The results of this study are consistent with the hypothesis that Fos positive neurons in the lateral segmental field of the reticular formation (FTL) between the solitary nucleus (NTS) and the ambigual nucleus (NA) were interneurons in the glottic closure response. In the experiment of the laryngeal evoked response in the cat, the origin of P3-N3-P4 was considered those neurons in the lateral segmental field of the reticular formation. Based on the latency, this result indicated that there were a few interneurons between the NTS and the NA.It is inferred that the laryngeal reflex pathway includes both excitatory and inhibitory internneurons by way of immunohistochemistry of GABA and glutamate. It might be surmised that one of the causes of the spasmodic dysphonia was the disturbance of the inhibitory pathway.