Morphological polarizations of sensory hair cells in the three otolithic organs of a teleost fish: fluorescent imaging of ciliary bundles

It has been suggested that the morphological polarity of sensory hair cells in the otolithic organs plays important roles in directional hearing in fi sh. In this study, we examined the hair cell polarization patterns in the s accule, utricle, and lagena of a releost fish, the sleeper goby (Dormitator latifrons). In contrast to using traditional scanning electron microscopy, we employed a simple and rapid method that enabled us to map the hair cell polarization patterns using immunocytochemical and confocal imaging techni ques. The hair cells in the caudal part of the saccular epithelium are orie nted dorsally and ventrally, with some variations in the caudal end. The ha ir cells in the rostral part have diverse morphological polarizations. The utricular hair cells fall into internal and external groups which have oppo sing polarizations. The lagenar hair cells are found in anterior and poster ior groups with approximately opposite polarizations. The saccular and lage nar epithelia are oriented perpendicular to the horizontal plane of the fis h, while the utricular epithelium lies on the horizontal plane. Thus, the s leeper goby's ear is morphologically capable of being a three-dimensional s ound detector. (C) 1998 Elsevier Science B.V. All rights reserved.