Corwin J T
Department of Otolaryngology-Head and Neck Surgery, University of Virginia, School of Medicine, Charlottesville 22908.
Exp Neurol. 1992 Jan;115(1):7-12. doi: 10.1016/0014-4886(92)90212-9.
The auditory organs of birds and mammals normally stop producing sensory hair cells during embryonic development, so loss of those cells later in life results in hearing deficits that have been considered irreversible. In contrast to this, the ears of some fish and amphibians produce hair cells continuously throughout life and even increase in sensitivity. The lateral line organs in the skin of fish and aquatic amphibians also contain hair cells and have long been known to be replaceable through regeneration. Recently, it was discovered that after acoustic trauma or antibiotic poisoning, injured hair cells in the mature auditory organs of birds also could be replaced through regeneration. This is especially notable because it occurs in populations of cells that are mitotically quiescent in undamaged ears. More recent investigations have focused on identifying the cells that give rise to new hair cells during regeneration. In the lateral line organs of salamanders, time-lapse video microscopy has revealed that surviving supporting cells divide to give rise to progeny that can differentiate either as hair cells or as supporting cells. Definitive identification of the progenitors of regenerated hair cells in the avian cochlea awaits further investigation, but evidence that points to two possible candidate cell types is discussed.
鸟类和哺乳动物的听觉器官在胚胎发育过程中通常会停止产生感觉毛细胞，因此这些细胞在生命后期的丧失会导致听力缺陷，而这种缺陷一直被认为是不可逆的。与此形成对比的是，一些鱼类和两栖动物的耳朵在一生中会持续产生毛细胞，甚至敏感度还会增加。鱼类和水生两栖动物皮肤中的侧线器官也含有毛细胞，并且长期以来已知其可通过再生进行替换。最近发现，在遭受声学创伤或抗生素中毒后，鸟类成熟听觉器官中受损的毛细胞也可以通过再生来替换。这一点尤其值得注意，因为它发生在未受损耳朵中处于有丝分裂静止状态的细胞群体中。最近的研究集中在确定再生过程中产生新毛细胞的细胞。在蝾螈的侧线器官中，延时视频显微镜显示，存活的支持细胞会分裂产生后代，这些后代可以分化为毛细胞或支持细胞。鸟类耳蜗中再生毛细胞祖细胞的确切鉴定有待进一步研究，但文中讨论了指向两种可能候选细胞类型的证据。
