Experimental Study on Hearing Impairment in Acoustic Neuromas

听神经瘤听力障碍的实验研究

基本信息

批准号：
63480385
负责人：
KANZAKI Jin
金额：
$ 3.58万
依托单位：
Keio University
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (B)
财政年份：
1988
资助国家：
日本
起止时间：
1988 至 1990
项目状态：
已结题

项目摘要

The relationship between cochlear blood flow (CBF) and cochlear electrical activity was investigated to better understand cochlear circulatory insufficiency, which is considered to be a cause of hearing loss acoustic neuroma.1. Experimental animal models for cochlear circulatory insufficiencyExperimental animal models for cochlear circulatory insufficiency were made by asphyxia, NO2 anoxia and obstruction of AICA.Changes in systemic blood pressure (BP) during asphyxia and NO2 anoxia were clearly associated with changes in CBF. At the initial stage of asphyxia, however, CBF did not change in spite of the decrease in BP. These discrepancies appeared to be related to autoregulation of CBF. There was no difference in the change in compound action potential of the eighth nerve (AP) between asphyxia and NO2 anoxia.Data from the experiment using AICA obstruction were insufficient to provide information on changes in AP as CBF decreased. However, the data indicated that the higher the CBF reduction rate, the higher the disappearing rate of AP.2. Effects of steroid hormone and hypothermia on cochlear circulatory insufficiencyAlthough changes in CBF following systemic administration of steroid hormone were not clearly observed, the recovery time of N1 (AP) latency became shorter with systemic administration of steroid hormone. Similar results were obtained with hypothermia. Based on the analysis of these results, we concluded that the reversibility of the cochlear activity in cochlear circulatory insufficiency could be improved by the administration of steroid and hypothermia.

研究了耳蜗血流（CBF）与耳蜗电活动之间的关系，以更好地理解耳蜗循环不足，这被认为是听力损失声学神经瘤的原因1。用于耳蜗循环循环不足的耳蜗循环系统动物模型的实验动物模型是通过窒息，NO2缺氧和AICA阻塞制成的。在窒息和NO2缺氧期间的系统性血压（BP）改变与CBF变化的变化明显相关。然而，在窒息的初始阶段，尽管BP减少，CBF并未改变。这些差异似乎与CBF的自动调节有关。窒息和NO2缺氧之间的第八神经（AP）的复合动作电位的变化没有差异。但是，数据表明CBF降低率越高，AP.2的消失率越高。类固醇激素和体温过低对类固醇激素的全身施用后，CBF的耳蜗循环不足的影响未明确观察到，随着类固醇激素的全身施用，N1（AP）潜伏期的恢复时间更短。体温过低也获得了相似的结果。基于对这些结果的分析，我们得出结论，可以通过类固醇和体温过低的给药来改善耳蜗循环不足中耳蜗活动的可逆性。