Chang J S, Popper A N, Saidel W M
Department of Zoology, University of Maryland, College Park 20742.
J Comp Neurol. 1992 Oct 22;324(4):621-40. doi: 10.1002/cne.903240413.
The ultrastructure of sensory hair cells in the utricle of the cichlid fish, Astronotus ocellatus, the oscar, was studied by transmission electron microscopy of serial ultrathin sections from different regions of the epithelium. Two distinctly different types of hair cell were found, one located in the striolar region of the epithelium and the other in the extrastriolar region. Striolar hair cells have a well-defined perinuclear cisterna located just below the nucleus, and large perinuclear mitochondria. Synaptic bodies of striolar cells are small and located in clusters, while those in extrastriolar cells are relatively large and individually dispersed. The extrastriolar hair cell closely resembles the amniote type II hair cell. On the basis of these data, and consistent with earlier studies, it appears that the striolar hair cells closely resemble amniote type I hair cells in many significant ways. Thus we have called them type I-like cells. The extrastriolar hair cells appear to be typical of eighth nerve mechanoreceptors commonly described for fish and closely resemble the amniote type II hair cell.
通过对丽鱼科鱼类眼斑星丽鱼（也称奥斯卡）椭圆囊上皮不同区域的连续超薄切片进行透射电子显微镜观察，研究了其感觉毛细胞的超微结构。发现了两种明显不同类型的毛细胞，一种位于上皮的纹状区，另一种位于纹状区以外的区域。纹状区毛细胞在细胞核正下方有一个界限分明的核周池，以及大型的核周线粒体。纹状区细胞的突触小体较小且成簇分布，而纹状区以外细胞的突触小体则相对较大且单个分散。纹状区以外的毛细胞与羊膜动物的II型毛细胞非常相似。基于这些数据，并与早期研究一致，纹状区毛细胞在许多重要方面似乎与羊膜动物的I型毛细胞非常相似。因此，我们将它们称为I型样细胞。纹状区以外的毛细胞似乎是鱼类中通常描述的第八神经机械感受器的典型代表，并且与羊膜动物的II型毛细胞非常相似。
