Functional significance of the gap junctions in the ion transport mechanism in the cochlea -molecular biological analysis

间隙连接在耳蜗离子传输机制中的功能意义-分子生物学分析

• 批准号: 10671581
• 负责人: KIKUCHI Toshihiko
• 金额: $ 0.58万
• 依托单位: Nagasaki University (1999)Tohoku University (1998)
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1998
• 资助国家: 日本
• 起止时间: 1998 至 1999
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10671581/
• 关键词: gap junction; connexin 26; connexin 31; Na,K-ATPase; Na-K-Cl cotransporter; endolymphatic potential; Brain-4; connexin26

1. Immunohistochemical localization of Na,K-ATPase, Na-K-Cl cotransporter, connexin 26 and connexin 31 in the mouse cochlea was studied in the present investigation. Intense Na,K-ATPase-like immunoreactivity was observed in the type II fibrocyte in the spiral ligament, suprastrial fibrocytes and marginal cells in the stria vascularis. The distribution pattern of Na-K-Cl cotransporter was comparable to that of Na,K-ATPase. Connexin 26 was densely distributed among the fibrocytes in the spiral ligament and along the basal cells of the stria vascularis. Connexin 31 was also widely distributed among the fibrocytes in the spiral ligament.2. The expression of Na,K-ATPase and connexin 26 was studied in the postnatal developmental process of the mouse cochlea. The expression patterns of Na,K-ATPase and connexin 26 in the fibrocytes in the spiral ligament coincided with the rapid growth and maturation of the endolymphatic potential.3. The endolymphatic potential was significantly decreased in the mutant mouse lacking Brain-4. It is suggested that a dysfunction of fibrocytes and an interruption of the transcellular route via gap junctions can cause a depression of endolymphatic potential in the cochlea of this mutant mouse.4. The perilymphatic perfusion of long-chain alcohol resulted in the depression of endolymphatic potential.These results obtained in the present study strongly suggest that the transcellular pathway via gap junctions plays a very important role in the generation of endolymphatic potential in the cochlea.

1.本研究应用免疫组织化学方法对小鼠耳蜗内Na，K-ATP酶、Na-K-Cl协同转运蛋白、连接蛋白26和连接蛋白31进行了定位研究。在螺旋韧带中的II型纤维细胞、血管纹中的血管纹上纤维细胞和边缘细胞中观察到强烈的Na，K-ATP酶样免疫反应。Na-K-Cl协同转运蛋白的分布模式与Na，K-ATP酶的分布模式相似。连接蛋白26密集分布于螺旋韧带的纤维细胞间和血管纹的基底细胞沿着分布。连接蛋白31也广泛分布于螺旋韧带的纤维细胞中.研究了Na，K-ATP酶和连接蛋白26在小鼠耳蜗生后发育过程中的表达。螺旋韧带内纤维细胞Na，K-ATP酶和连接蛋白26的表达模式与内淋巴潜能的快速生长和成熟相吻合.在缺乏Brain-4的突变小鼠中，内淋巴电位显著降低。这表明纤维细胞功能障碍和通过缝隙连接的跨细胞途径的中断可以导致该突变小鼠耳蜗内淋巴电位的抑制。长链酒精外淋巴灌流可引起耳蜗内淋巴电位的降低，提示通过缝隙连接的跨细胞通路在耳蜗内淋巴电位的产生中起重要作用。

项目成果

Minowa O,Ikeda K,Sugitani Y,Osbima T,Nakai S.,Katori Y,Suzuki M,Furukawa M,Kawase T,Zheng Y,Ogura N,Asada Y,Watanabe K,Yamanaka H,Gotoh S,Nishi-Takeshima M,Hamada H,Sugimoto T,Kikuchi T,Takasaka T,Noda T.: "Altered cochlear fibrocytes in a mouse model of

Minowa O、Ikeda K、Sugitani Y、Osbima T、Nakai S.、Katori Y、Suzuki M、Furukawa M、Kawase T、Zheng Y、Ogura N、Asada Y、Watanabe K、Yamanaka H、Gotoh S、Nishi-Takeshima M

Xia A-P, Kikuchi T., hozawa K., Katori Y., Takasaka T.: "expression of connexin 26 and Na, k-ATPase in the developing mouse cochlear lateral wall: functional implications"Brain Research. 846. 106-111 (1999)

Xia A-P、Kikuchi T.、hozawa K.、Katori Y.、Takasaka T.：“连接蛋白 26 和 Na、k-ATP 酶在发育中的小鼠耳蜗侧壁中的表达：功能意义”脑研究。

Xia A.P, Kikuchi T, Hozawa K, Katori Y, Takasaka T.: "Expression of connexin 26 and Na,K-ATPase in the developing mouse cochlear lateral wall: functional implications"Brain Resaerch. 846. 106-111 (1999)

Xia A.P、Kikuchi T、Hozawa K、Katori Y、Takasaka T.：“连接蛋白 26 和 Na,K-ATP 酶在发育中的小鼠耳蜗侧壁中的表达：功能意义”脑研究。