铁缺乏大鼠畸变产物耳声发射与耳蜗毛细胞的改变

目的 观察不同饲养期铁缺乏大鼠畸变产物耳声发射（DPOAE）的改变与耳蜗毛细胞改变的关系，探讨铁缺乏引起听毛细胞损伤的可能机制。方法 以缺铁饮食饲养法复制缺铁Wistar大鼠模型33只，标准饮食喂养33只作对照。每组分别于喂养第4，8，12周各随机取11只测双耳DPOAE幅值，并处死做耳蜗扫描电镜。结果 缺铁组第4周，36．4％耳数（8／22）出现DPOAE幅值中、高频率段下移，但扫描电镜下未发现毛细胞病理改变；缺铁至第8周，59．1％耳数（13／22）出现DPOAE幅值中、高频率段程度较重的下移，13耳中，3个耳蜗出现不同程度外毛细胞静纤毛散乱、扭曲、倒伏、融合等病理改变；缺铁至第12周，55．6％耳数（10／18）DPOAE幅值中、高频率段下移。10耳中，5个耳蜗出现不同程度外毛细胞静纤毛散乱、扭曲、倒伏、融合。缺失等病理改变，病变范围扩大。结论铁缺乏可使Wistar大鼠DPOAE以及耳蜗毛细胞发生改变。DPOAE改变发生在毛细胞改变之前，DPOAE幅值下降到一定程度延缓或停止，但毛细胞病理改变仍有加重趋势。

Changes of distortion product otoacoustic emissions and cochlear hair cells in iron-deficient rats

Objective To obsreve DPOAE change in rats at different iron-deficient stages. Methods Sixty-six healthy Wistar rats were randomly divided into control group (33 rats) and iron-deficient group (33 rats). The iron-deficient group were fed with iron-different diet. DPOAEs were measured and cochlear hair cell were examined by scanning electron microscopy at the 4th,8th and 12th week in both groups. The iron-deficient diet was continued to the 8th week but stopped at the 12th week. Results A significant decrease of DPOAE threshold levers at 2 kHz,4 kHz in iron-deficient group was obserred at the 4th week, More frequencies were affected as the iron-deficient diet was continued to the 8th week, but stop at the 12th week. Conclusions Iron-deficient can effect the function and structure of cochlear hair cells.