Cotanche D A, Petrell A, Picard D A
Department of Anatomy & Neurobiology, Boston University School of Medicine, MA 02118.
Ciba Found Symp. 1991;160:131-42; discussion 142-50. doi: 10.1002/9780470514122.ch7.
Exposure of the chick cochlea to intense acoustic overstimulation leads to rapid changes in the structural organization of hair cells and supporting cells. During the noise exposure the surface areas of the hair cells are reduced and, concomitantly, the adjacent supporting cells expand. If the exposure continues long enough hair cells bleb out apically and are ejected from the sensory epithelium. Surviving hair cells begin to expand their surface areas again within 24 hours after the termination of noise exposure. By 48 hours of recovery most of the hair cells that have died are ejected from the epithelium and new, regenerating hair cells begin to sprout immature stereociliary bundles. The regenerating stereociliary bundles undergo steps in their maturation that are equivalent to those seen during the normal embryonic development of hair cells. The extent and timing of recovery in the chick cochlea correlates with the length of the noise exposure. Shorter exposures (approximately 12 hours) result in only a few regenerating hair cells but the basilar papilla recovers almost completely within 14 days. Longer exposures (approximately 24 hours) lead to the production of more new hair cells but the recovery of the basilar papilla is incomplete, even after 28 days of recovery.
将雏鸡耳蜗暴露于强烈的声学过度刺激下会导致毛细胞和支持细胞的结构组织迅速发生变化。在噪声暴露期间，毛细胞的表面积减小，与此同时，相邻的支持细胞扩张。如果暴露持续足够长的时间，毛细胞会在顶端形成气泡并从感觉上皮中排出。存活的毛细胞在噪声暴露终止后的24小时内开始再次扩大其表面积。到恢复48小时时，大多数死亡的毛细胞会从上皮中排出，新的、正在再生的毛细胞开始长出未成熟的静纤毛束。正在再生的静纤毛束经历的成熟步骤与毛细胞正常胚胎发育过程中所见的步骤相当。雏鸡耳蜗恢复的程度和时间与噪声暴露的时长相关。较短时间的暴露（约12小时）仅导致少数再生毛细胞，但基底乳头在14天内几乎完全恢复。较长时间的暴露（约24小时）会产生更多新的毛细胞，但即使在恢复28天后，基底乳头的恢复也不完全。
