We have reported that the activity of the mechanoreceptors against vibration in the subglottic mucosa enhances reflexive contraction of the contralateral thyroarytenoid muscle (TA) primarily via the recurrent laryngeal nerve (RLN) and partially via the internal branch of the superior laryngeal nerve (ISLN), both of which are indispensable for reflexive laryngeal control. Morphologically, some parts of the laryngeal mucosa receive sensory innervation from both RLN and ISLN.
In the present study, we recorded respiratory neurograms of the Galen anastomosis (GA) of spontaneously breathing cats under general anesthesia. Rhythmic inspiratory activities were recorded from GA and they were synchoronous with the activities of the posterior cricoarytenoid muscle (PCA). Weak expiratory activities were also recorded from GA. Sections of the nerve branches for the adductor muscles did not affect the rhythmic activities of GA. When the nerve branch to PCA was sectioned, the inspiratory activities of GA disappeared. An additional section of the main trunk of RLN resulted in disappearance of the remaining expiratory activities.
