小鼠耳蜗Na-K-2Cl联合转运子-1的定位及其缺失后的耳蜗组织学改变

Localization of NKCC1 in the Cochlea of Mouse and Histological Changes of the Cochlea of NKCC1-Knockout Mouse

熊浩;褚汉启;黄孝文;韩芳;吴振恭;周良强;崔永华;

1:华中科技大学同济医学院附属同济医院耳鼻咽喉科

2:华中科技大学同济医学院附属同济医院耳鼻咽喉科

3:华中科技大学同济医学院附属同济医院耳鼻咽喉科

4:华中科技大学同济医学院附属同济医院耳鼻咽喉科

摘要
目的探讨耳蜗钾循环途径中Na-K-2Cl联合转运子-1(Na-K-2Clcotransporter-1,NKCC1)在小鼠耳蜗的分布及NKCC1基因敲除后耳蜗组织学的改变。方法选用10只C57BL/6J小鼠((NCKK1+/+)和5只NKCC1基因敲除小鼠(NKCC1-/-),应用听性脑干反应(auditorybrainstemresponse,ABR)分别检测NCKK1+/+小鼠和NKCC1-/-小鼠的听功能,采用免疫组织化学及甲苯胺蓝染色的方法观察NKCC1在NCKK1+/+小鼠耳蜗的定位及NKCC1-/-小鼠耳蜗组织学的变化。结果NCKK1+/+小鼠ABR平均阈值为31±5.36dBSPL,而NKCC1-/-小鼠听力完全丧失。NKCC1在NCKK1+/+型小鼠耳蜗主要分布在血管纹上皮(边缘细胞)和螺旋韧带下部纤维细胞,在纹上区和螺旋缘处的纤维细胞中也有适度表达;NKCC1-/-小鼠耳蜗前庭膜塌陷,中阶完全消失,内毛细胞、外毛细胞、支持细胞减少,Corti隧道消失。结论NKCC1在耳蜗的定位与耳蜗钾循环密切相关,NKCC1缺失会导致耳蜗正常结构的破坏,继而影响耳蜗生理功能。
关键词
Na-K-2Cl联合转运子;基因敲除;钾循环;免疫组织化学
基金项目(Foundation):
国家自然科学基金资助项目(编号30371526);; 湖北省自然科学基金资助项目(编号2002AB127)
作者
熊浩;褚汉启;黄孝文;韩芳;吴振恭;周良强;崔永华;
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