Suzuki M, Kitano H, Yazawa Y, Kitajima K
Department of Otolaryngology, Shiga University of Medical Science, Seta, Otsu, Japan.
Acta Otolaryngol. 1998 Sep;118(5):712-6. doi: 10.1080/00016489850183232.
Changes in ambient pressure can elicit the vertigo and bodily disequilibrium known clinically as alternobaric vertigo. Our previous studies showed that changes in middle ear pressure altered the activity of the primary vestibular neuron, and the finding suggests that the pressure-induced vestibular response causes alternobaric vertigo. To investigate the roles played by the round window (RW) and the oval window (OW) in the vestibular response induced by pressure, we measured the change in perilymphatic pressure and the firing rates of primary vestibular neurons after the application of positive or negative pressure to the middle ear. We found an increase in the pressure-induced vestibular response in the group with a closed OW, and a decrease in the group with a closed RW. Measurements showed that the amplitude of the change in perilymphatic pressure in the group with a closed OW did not differ from that in the control group, whereas the amplitude of the perilymphatic pressure change in the group with a closed RW was significantly reduced. A discrepancy between the number of neurons responding and the amplitude of the perilymphatic pressure change in the closed OW group suggests that the vestibular response induced by the change in middle ear pressure was not related solely to the magnitude of the pressure change in the inner ear, but also involved the oval and round windows.
环境压力的变化可引发临床上称为交替性气压性眩晕的眩晕和身体失衡。我们之前的研究表明，中耳压力的变化会改变初级前庭神经元的活动，这一发现表明压力诱导的前庭反应会导致交替性气压性眩晕。为了研究圆窗（RW）和卵圆窗（OW）在压力诱导的前庭反应中所起的作用，我们在向中耳施加正压或负压后，测量了外淋巴压力的变化以及初级前庭神经元的放电频率。我们发现，卵圆窗封闭组的压力诱导前庭反应增加，而圆窗封闭组的反应则减少。测量结果显示，卵圆窗封闭组的外淋巴压力变化幅度与对照组无差异，而圆窗封闭组的外淋巴压力变化幅度则显著降低。卵圆窗封闭组中反应神经元数量与外淋巴压力变化幅度之间的差异表明，中耳压力变化诱导的前庭反应不仅与内耳压力变化的幅度有关，还涉及卵圆窗和圆窗。
