Cochlear Dysfunction and Free Radicals : hydroxyl radicals, metallic elements, steroid hormones and SOD

耳蜗功能障碍和自由基：羟基自由基、金属元素、类固醇激素和 SOD

• 批准号: 10470351
• 负责人: HARA Akira
• 金额: $ 2.56万
• 依托单位: University of Tsukuba
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1998
• 资助国家: 日本
• 起止时间: 1998 至 2001
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-10470351/
• 关键词: Cochlear dysfunction; Free radicals; Hydrnxyl radicals; NO; Transient ischemia; Steroid hormone; Iron chelator; Acoustic trauma; アスフィキシア; フリーラジカルスカベンジャー; ヒドロモシルラジカル; NOS阻害薬; 鉄; 虚血; マンニトール

Metallic elements : Concentration of free iron transiently increased after local ischemia or asphyxia. The depression of DPOAE after local ischemia was improved by cochlear perfusion of an iron chelator.Hydroxyl radicals : The generation of hydroxyl radicals was recognized in the perilymph after local ischemia, and was continued for 2 hours or more after reperfusion. The threshold shift of CAP after ischemia was significantly reduced by administration of scavengers to hydroxyl radicals.Steroid hormones : The high level glucocorticoid receptor mRNA was revealed in the cochlea of the guinea pig. The level of glucocorticoid receptor mRNA significantly decreased immediately after exposure to the acoustic overstimulation. The concentration of glucocorticoid was high and maintained for a long period in the cochlea.Nitric oxide (NO) : Significant increase of NO concentration was recognized after reperfusion. NO inhibitors alleviated the CAP threshold shift after local ischemia.

金属元素：局部缺血或窒息后游离铁浓度短暂升高。局部缺血后DPOAE的抑制通过铁螯合剂的耳蜗灌注得到改善。 羟基自由基：局部缺血后在外淋巴中发现羟基自由基的产生，并且在再灌注后持续2小时或更长时间。通过给予羟基自由基清除剂，缺血后CAP的阈值移动显着降低。类固醇激素：在豚鼠的耳蜗中发现高水平的糖皮质激素受体mRNA。暴露于声音过度刺激后，糖皮质激素受体 mRNA 水平立即显着下降。糖皮质激素的浓度在耳蜗中高且维持较长时间。一氧化氮(NO)：再灌注后发现NO浓度显着增加。 NO 抑制剂减轻了局部缺血后 CAP 阈值的变化。

项目成果

原 晃: "内耳恒常性機構-液性制御「内耳液の動態とグルココルチコイド」"Otology Japan. 8. 1-5 (1998)

Akira Hara：“内耳稳态机制 - 体液控制‘内耳液体和糖皮质激素的动力学’”Otology Japan。 8. 1-5 (1998)

Tobita T: "Trial of measurement glucocorticoid in the cochlea"Otology Japany. 11 :. 108-111 (2001)

Tobita T：“测量耳蜗中糖皮质激素的试验”Otology Japany。

Keiji Tabuchi: "The poly(ADP-ribose) synthase inhibitor, 3-aminobenzamide, alleriates cochlear dysfunction induced by transient ischemia"Annals of Otology,Rhinology and Laryngology. (in press). (2000)

Keiji Tabuchi：“聚（ADP-核糖）合酶抑制剂 3-氨基苯甲酰胺可缓解短暂性缺血引起的耳蜗功能障碍”《耳科、鼻科和喉科年鉴》。

Akira Hara: "Hydroxyl radical formation in the perilymph of asphyxic guinea pig"Hearing Research. 143. 110-114 (2000)

原晃：“窒息豚鼠外淋巴中的羟基自由基形成”听力研究。

Tabuchi K.: "Effect of 7-nitroindazole upon cochlear dysfunction induced by transient local anoxia"Annals of Otology, Rhinology and Laryngology. 109. 715-719 (2000)

Tabuchi K.：“7-硝基吲唑对短暂局部缺氧引起的耳蜗功能障碍的影响”耳科、鼻科和喉科年鉴。