Erulkar J S, O'Brien D A, Saunders J C
Department of Otorhinolaryngology: Head and Neck Surgery, University of Pennsylvania, Philadelphia 19104-4283, USA.
Scanning Microsc. 1996;10(4):1127-40; discussion 1140-2.
Exposure to intense sound produces a well-defined "patch" lesion on the chick basilar papilla in which 30-35% of the short hair cells are lost. The present study compares various aspects of sensory hair bundle morphology on surviving hair cells in the patch lesion with hair bundles from matched locations on nonexposed control papilla immediately after removal from the exposure and 12-days post exposure. The height and thickness of the hairs, the total number of hairs in the bundle, the width of the bundle, and the area and perimeter of the apical surface of the hair cell were quantified from scanning electron microscope photomicrographs. An attempt was also made to determine if there was a consistent microstructure to the pattern of hair cell loss within the lesion area. Similar observations in 12-day recovered ears are also presented. The results indicated that stereocilia height increased and width decreased on surviving hair cells in the exposed ear. The width of the hair bundle, the hair cell surface area, and perimeter also decreased. However, the number of hairs per cell remained unchanged, and there was no evidence of any consistent organization to the hair cell loss within the patch across a number of specimens. These observations indicated that the hair bundles on short hair cells underwent changes as a consequence of intense sound exposure. The results after 12 days of recovery were complicated by developmental changes on the papilla and incomplete maturation of the newly regenerated hair cells. It remains to be seen whether these changes were the result of cell sampling in the sound-damaged ear or were due to true structural alterations within the sensory hairs themselves.
暴露于高强度声音会在雏鸡的基底乳头产生一个界限分明的“斑块”损伤，其中30%-35%的短毛细胞会丢失。本研究比较了斑块损伤中存活毛细胞上感觉毛束形态的各个方面，与刚从暴露环境中取出时以及暴露后12天，未暴露的对照乳头中匹配位置的毛束形态。从扫描电子显微镜显微照片中量化了毛的高度和厚度、毛束中的毛总数、毛束宽度以及毛细胞顶端表面的面积和周长。还试图确定损伤区域内毛细胞丢失模式是否存在一致的微观结构。也展示了在恢复12天的耳朵中的类似观察结果。结果表明，暴露耳中存活毛细胞上的静纤毛高度增加而宽度减小。毛束宽度、毛细胞表面积和周长也减小。然而，每个细胞的毛数量保持不变，并且在多个标本的斑块内，没有证据表明毛细胞丢失存在任何一致的组织模式。这些观察结果表明，短毛细胞上的毛束因高强度声音暴露而发生了变化。恢复12天后的结果因乳头的发育变化和新再生毛细胞的不完全成熟而变得复杂。这些变化是声音损伤耳中细胞采样的结果，还是由于感觉毛本身真正的结构改变，仍有待观察。
