Morphometry of otoconia in the utricle and saccule of developing Japanese quail
- 作者：Dickman ; J. David ; Huss ; David ; Lowe ; Melissa
- 关键词：Otolith ; Vestibular ; Development ; Inner ear ; Balance ; Spatial orientation ; E ; embryologic stage ; L/W ; length&ndash ; width ratio ; OC90 ; otoconin 90 protein ; OTOP1 ; otopetrin protein ; SEM ; scanning electron microscopy ; PH ; post-hatch day
- 刊名：Hearing Research
- 出版年：2004
- 期刊代码：111_03785955
- 类别：med
- 出版时间：February, 2004
- 卷：188
- 期：1-2
- 页码：89-103
- 文件大小：1.25 M
摘要
The development of otoconia in the utricular and saccular maculae from initial embryonic formation to adult stages was examined in Japanese quails. Both the morphology and size of the otoconia were quantified at different developmental stages. It was observed that the otoconia were initially formed on embryologic stage E5 in the saccule and E6 in the utricle. Otolith mass areas increased in a sigmoidal growth pattern, with saccular otolith areas being smaller than the utricular mass areas. Saccular otolith masses reached adult values at embryonic stage E12 and utricular areas reached adult values at post-hatch day 7. Mature individual otoconia were characterized by a barrel shape with two trihedral faceted ends. However, initial formation of otoconia at E5 (saccular) and E6 (utricular) maculae was characterized by a double fluted morphology that consisted of an hourglass shape with extended fins forming trihedral angles of 120°. Double fluted otoconia rapidly filled, so that by embryonic day 8 mature otoconia dominated the maculae for the remainder of development through adulthood. Thus, a progression from double fluted to mature forms was noted. Mature utricular otoconia in adult quails averaged 11 μm in length and 5 μm in width, with length/width ratios of approximately 2.5:1, for all size ranges. Saccular otoconia were smaller, having about 70%the size of utricular otoconia in both length and width. During development, the average size and range of individual otoconia increased nearly linearly for both otolith organs. In the utricular macula, large otoconia were concentrated in the lateral regions of the epithelium. In contrast, otoconia of various sizes were distributed uniformly across the surface of the saccular macula.