Satar B, Ozkaptan Y, Sürücü H S, Oztürk H
Department of Otolaryngology, Head and Neck Surgery, Gülhane Military Medical Academy, 06010 Etlik-Ankara, Turkey.
Otol Neurotol. 2001 Nov;22(6):786-9. doi: 10.1097/00129492-200111000-00012.
The goals of this study were to identify the effects of hypercholesterolemia on the cochlea and to find out where the pathologic changes first occur.
Some authors have stated that hypercholesterolemia alone does not produce auditory dysfunction. Others propose that auditory dysfunction is caused by glycogen accumulation and other alterations on cochlear ultrastructure.
Twenty guinea pigs were classified as a control group fed with a normal diet, and a cholesterol group of 24 animals was given a diet composed of 1 g cholesterol per day for 4 months. The hearing acuity of the animals before the diets was compared with that after the diets by means of auditory brainstem responses. The basal and apical turns of the cochleas were examined by light microscopy and transmission electron microscopy.
The control group showed normal cochlear ultrastructures consistent with normal hearing thresholds, whereas the cholesterol group had profound edema in the strial marginal layer and slight edema in the outer hair cells, in line with data from auditory brainstem responses revealing changes in hearing sensitivity in various degrees. The pathologic changes in the basal turn and the stria vascularis were qualitatively prominent in comparison with those of the apical turn and the outer hair cell.
These observations confirm that hypercholesterolemia alone may cause auditory dysfunction if dietary cholesterol is kept at a high level for a long time. Alterations attributed to hypercholesterolemia begin in the stria vascularis and then spread over the outer hair cells, mainly in the basal turn.
本研究的目的是确定高胆固醇血症对耳蜗的影响，并找出病理变化首先发生的部位。
一些作者指出，单纯的高胆固醇血症不会导致听觉功能障碍。另一些人则认为，听觉功能障碍是由糖原积累和耳蜗超微结构的其他改变引起的。
将20只豚鼠分为对照组，给予正常饮食；24只动物组成胆固醇组，每天给予含1克胆固醇的饮食，持续4个月。通过听觉脑干反应比较动物饮食前后的听力。用光镜和透射电镜检查耳蜗的基底转和顶转。
对照组耳蜗超微结构正常，听力阈值正常；而胆固醇组血管纹边缘层有严重水肿，外毛细胞有轻微水肿，这与听觉脑干反应数据显示的不同程度的听力敏感性变化一致。与顶转和外毛细胞相比，基底转和血管纹的病理变化在性质上更为突出。
这些观察结果证实，如果长期保持高胆固醇饮食，单纯的高胆固醇血症可能会导致听觉功能障碍。高胆固醇血症引起的改变始于血管纹，然后扩散到外毛细胞，主要在基底转。
