Spontaneous nasal oscillations in dog. A mucosal expression of the respiration-related activities of cervical sympathetic nerve.

We studied the respiratory oscillations of the nasal mucosa in dogs. Even after temporarily stopping the respirator, intranasal balloon pressure showed respiration-related oscillations (spontaneous nasal oscillations). These spontaneous oscillations were recorded in all 21 dogs. Spontaneous nasal oscillations were not abolished even after thoracotomy, vagotomy and vidian neurectomy. Only cervical sympathectomy could to a large extent abolish the spontaneous nasal oscillations. Furthermore, the spontaneous nasal oscillations were found to be synchronized with the respiration-related fluctuations of cervical sympathetic nerve activities. Rhythms of the spontaneous nasal oscillations were not dependent on the rates of artificial ventilation, but were closely related to the rates of spontaneous respiration before administering the muscle relaxant. On some occasions, we recognized remarkable differences in the height of waves of the spontaneous nasal oscillations between the sides of the body. On eight occasions in 5 dogs, reciprocal changes of the dominant side of bilateral spontaneous nasal oscillations were noted which might be an expression of the nasal cycle.