An Investigation of the Protective Reflex Mechanism of the Larynx.

在吞咽的第二阶段，喉参与保护反射。本研究通过形态学和电生理学的研究来阐明猫吞咽的神经组织结构。在咽喉粘膜中观察到游离神经末梢、味蕾和串珠状神经末梢。提示喉粘膜中存在机械感受器、化学感受器和多模态感受器。这些受体的结构和特性适合于吞咽的诱发。来自咽喉区域的大部分冲动被带入孤束核的间质亚核。感觉信息在间质亚核集中处理，是引起保护性反射所必需的。在吞咽过程中爆发的吞咽相关神经元分为三种类型。一部分II型神经元构成吞咽的中枢模式发生器。与吞咽有关的皮层位于眶回。该区域可以调节吞咽诱发的兴奋性。从头皮记录喉感觉诱发电位（LSEP），它是由电刺激上级喉神经诱发的脑干和皮层的短潜伏期电位组成，并确定了发生源。

The larynx participates in protective reflex during second stage of the swallowing. In this study, morphological and electrophysiological investigations were performed to clarify the neural organization of the swallowing in the cat.The free nerve ending, taste buds and beaded nerve terminals were observed in the pharyngolaryngeal mucosa. It is proposed that mechanoreceptors, chemoreceptors and polymodal receoptors exist in the laryngeal mucosa. The strucures and characteristics of these receptors are appropriate for elicitation of the swallowing. The majority of the impulses from the pharyngolaryngeal region are carried into the interstitial subnucleus of the nucleus tractus solitarius. The sensory informations, which are essential for elicitaion of the protective reflex, are converged and processed in the interstitial subnucleus. The swallowing related neurons which burst during swallowing are classified into three types. A part of type II neurons constitute the central pattern generator for swallowing. The region of the cortex related to the swallowing was located in the orbital gyrus. This region may modulate the excitability in the elicitation of the swallowing. LSEP (laryngeal sensory evoked potential), which was consisted of short latent potentials in the brainstem and cortex evoked by electrical stimulation of the superior laryngeal nerve, was recorded from the scalp and generator sources were determined.