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，游离铁浓度一过性升高。局部缺血后DPOAE的抑制可通过耳蜗铁螯合剂的灌流得到改善。羟基自由基：局部缺血后外淋巴液中可识别羟基自由基的产生，再灌流后持续2小时以上。给予羟基自由基清除剂可显著降低豚鼠脑缺血后CAP阈值漂移。类固醇激素：豚鼠耳蜗糖皮质激素受体基因表达水平较高。声学过度刺激后即刻糖皮质激素受体基因表达水平明显下降。耳蜗糖皮质激素浓度较高，且维持较长时间。一氧化氮(NO)：再灌流后NO浓度明显升高。NO抑制剂可减轻局部缺血后CAP阈值的漂移。

项目成果

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。

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。

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》。

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)

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。