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目的：探讨应用强化铁营养对抗稳态噪声致聋作用的可能性。方法：４０只健康幼龄Ｗｉｓｔａｒ大鼠按随机化原则分为两组，每组２０只：Ａ组喂标准饲料；Ｂ组喂强铁化饲料。将Ａ、Ｂ两组大鼠同时暴露于１１０ｄＢＳＰＬ２０～１００００Ｈｚ稳态白噪声，持续４０ｍｉｎ。根据暴露前后听性脑干反应（ＡＢＲ）阈差值判定听力阈移，扫描电镜及光镜下观察耳蜗显微结构和听毛细胞表面超微结构变化。结果：暴露后２ｈ，３ｄ和１１ｄ的Ｂ组听力阈移值显著小于Ａ组；暴露后２１ｄ，虽然两组听力阈移均数值的差异无显著意义，但Ａ组ＡＢＲ阈值均数仍显著大于该组大鼠噪声暴露前平均听阈。扫描电镜下观察，暴露后２ｈ的Ａ组大鼠外毛细胞静纤毛出现严重扭曲、倒伏、排列紊乱等病理变化，３ｄ后，上述病变明显减轻，２１ｄ后，部分听毛细胞静纤毛排列紊乱仍未能完全恢复。在Ｂ组大鼠，外毛细胞静纤毛暴露２ｈ后有轻度扭曲及排列紊乱，３ｄ后这些病变基本恢复，２１ｄ后外毛细胞静纤毛形态完全恢复正常。结论：强化铁营养具有对抗稳态噪声听损伤作用，其机制可能与其对含铁酶类活性的增强作用有关。
Objective: To explore the possibility of applying iron fortification to deafness against steady-state noise. Methods: Forty healthy Wistar rats were randomly divided into two groups according to the principle of randomization: group A was fed with standard feed; group B was fed with iron-enriched feed. The A and B groups of rats were simultaneously exposed to steady-state white noise of 110dBSPL20 ~ 10000Hz for 40min. The hearing thresholds were determined according to the difference of threshold of auditory brainstem response (ABR) before and after exposure. The ultrastructure of cochlear ultrastructure was observed under scanning electron microscope and light microscope. Results: The hearing threshold of group B at 2h, 3d and 11d after exposure was significantly lower than that of group A, and 21d after exposure, although there was no significant difference in hearing threshold between two groups, the mean ABR threshold in group A was still significantly higher than that of group A The mean hearing threshold of rats before noise exposure. Scanning electron microscopy showed that after 2 hours of exposure, the outer cilia of outer hair cells in group A appeared serious distortion, lodging and disordered pathological changes. After 3 days, the above lesions were significantly alleviated. After 21 days, Failure to fully recover. In group B, the outer hair cells were slightly twisted and disordered after they were exposed for 2 hours. After 3 days, these lesions recovered, and the morphology of outer cilia remained intact after 21 days. CONCLUSION: Fortified iron nutrition has a protective effect against steady-state noise and its mechanism may be related to the enhancement of iron-containing enzyme activity.