Development of the Sensory Receptor Cells in the Utricular Macula

1978 ◽  
Vol 86 (2) ◽  
pp. ORL-297-ORL-304 ◽  
Author(s):  
Thomas R. Van De Water ◽  
Jan Wersäll ◽  
Matti Anniko ◽  
Hans Nordeman

Normal CBA mice were timed for the developmental stage by the vaginal plug technique. The day of copulatory plug observance was designated as gestation day one. The developmental characteristics of the utricular macula sensory epithelium is described on an ultrastructural level from the 15th to the 19th day of gestation (approximate day of birth). The following pertinent observations are reported: (1) the formation of stereocilia begins prior to the 15th day and continues to approximately the 18th day, (2) the formation of the stereocilia suggests a mechanism of gradual transformation of existing cell surface microvilli, (3) the onset of the genesis of stereocilia precedes neuronal contact and cuticular plate formation, (4) stereocilia rootlets are forming before cuticular plate formation, (5) utricular sensory hair cells have undergone significant ultrastructural differentiation prior to the development of synaptic contacts, and (6) nerve chalice formation of type I sensory cells begins on the 18th day and is still incomplete at birth.

1998 ◽  
Vol 79 (4) ◽  
pp. 2235-2239 ◽  
Author(s):  
John S. Oghalai ◽  
Jeffrey R. Holt ◽  
Takashi Nakagawa ◽  
Thomas M. Jung ◽  
Newton J. Coker ◽  
...  

Oghalai, John S., Jeffrey R. Holt, Takashi Nakagawa, Thomas M. Jung, Newton J. Coker, Herman A. Jenkins, Ruth Anne Eatock, and William E. Brownell. Ionic currents and electromotility in inner ear hair cells from humans. J. Neurophysiol. 79: 2235–2239, 1998. The upright posture and rich vocalizations of primates place demands on their senses of balance and hearing that differ from those of other animals. There is a wealth of behavioral, psychophysical, and CNS measures characterizing these senses in primates, but no prior recordings from their inner ear sensory receptor cells. We harvested human hair cells from patients undergoing surgical removal of life-threatening brain stem tumors and measured their ionic currents and electromotile responses. The hair cells were either isolated or left in situ in their sensory epithelium and investigated using the tight-seal, whole cell technique. We recorded from both type I and type II vestibular hair cells under voltage clamp and found four voltage-dependent currents, each of which has been reported in hair cells of other animals. Cochlear outer hair cells demonstrated electromotility in response to voltage steps like that seen in rodent animal models. Our results reveal many qualitative similarities to hair cells obtained from other animals and justify continued investigations to explore quantitative differences that may be associated with normal or pathological human sensation.


1989 ◽  
Vol 109 (4) ◽  
pp. 1711-1723 ◽  
Author(s):  
M S Tilney ◽  
L G Tilney ◽  
R E Stephens ◽  
C Merte ◽  
D Drenckhahn ◽  
...  

The sensory epithelium of the chick cochlea contains only two cell types, hair cells and supporting cells. We developed methods to rapidly dissect out the sensory epithelium and to prepare a detergent-extracted cytoskeleton. High salt treatment of the cytoskeleton leaves a "hair border", containing actin filament bundles of the stereocilia still attached to the cuticular plate. On SDS-PAGE stained with silver the intact epithelium is seen to contain a large number of bands, the most prominent of which are calbindin and actin. Detergent extraction solubilizes most of the proteins including calbindin. On immunoblots antibodies prepared against fimbrin from chicken intestinal epithelial cells cross react with the 57- and 65-kD bands present in the sensory epithelium and the cytoskeleton. It is probable that the 57-kD is a proteolytic fragment of the 65-kD protein. Preparations of stereocilia attached to the overlying tectorial membrane contain the 57- and 65-kD bands. A 400-kD band is present in the cuticular plate. By immunofluorescence, fimbrin is detected in stereocilia but not in the hair borders after salt extraction. The prominent 125 A transverse stripping pattern characteristic of the actin cross-bridges in a bundle is also absent in hair borders suggesting fimbrin as the component that gives rise to the transverse stripes. Because the actin filaments in the stereocilia of hair borders still remain as compact bundles, albeit very disordered, there must be an additional uncharacterized protein besides fimbrin that cross-links the actin filaments together.


1992 ◽  
Vol 337 (1282) ◽  
pp. 457-469 ◽  

The osphradium of Campanile symbolicum Iredale, 1917 is a gill-like, bipectinate sense organ, which is located at the left side of the mantle roof. The mass of the deeply clefted sensory epithelium of the leaflets is built up by sensory cells, which are provided with deeply invaginated aberrant cilia and large cytosomes containing pigment formations. In addition, many free nerve processes are present, bearing a single or few sensory cilia with accessory centrioles. Polyciliary cells are interspersed. A cell type with netlike or concentrically arranged smooth endoplasmic reticulum is commonly found near the central axis of the osphradium . The central zone of each leaflet includes nervous tissue and a complicated muscular grid, with pore cells and fibroblasts also present. Based on the fine-structural data the functional and ecological significance of the osphradium of Campanile symbolicum is discussed. The com bination of herbivory and a lamellar osphradium is rare among the Gastropoda, suggesting that the osphradium of Campanile might also be involved in reproductive biology. Many fine-structural features of the osphradium of Campanile symbolicum are unique among the gastropods and reflect the phylogenetic isolation of this relict snail. The net-like cell type, however, is probably homologous with the so-called Si4 cell in the rem aining caenogastropods, for which a largely different osphradial fine-structure is diagnostic. The affinities of Campanile symbolicum are probably closer to the Caenogastropoda than to the Allogastropoda and Euthyneura. With present knowledge it might be best classified near the base or even as the first clade within the Caenogastropoda.


ORL ◽  
1971 ◽  
Vol 33 (5) ◽  
pp. 304-311 ◽  
Author(s):  
K. Watanuki ◽  
H.F. Stupp ◽  
A. Meyer zum Gottesberge

2019 ◽  
Vol 379 (3) ◽  
pp. 459-471 ◽  
Author(s):  
Lejo Johnson Chacko ◽  
Consolato Sergi ◽  
Theresa Eberharter ◽  
Jozsef Dudas ◽  
Helge Rask-Andersen ◽  
...  

AbstractExpression patterns of transcription factors leucine-rich repeat-containing G protein-coupled receptor 5 (LGR5), transforming growth factor-β-activated kinase-1 (TAK1), SRY (sex-determining region Y)-box 2 (SOX2), and GATA binding protein 3 (GATA3) in the developing human fetal inner ear were studied between the gestation weeks 9 and 12. Further development of cochlear apex between gestational weeks 11 and 16 (GW11 and GW16) was examined using transmission electron microscopy. LGR5 was evident in the apical poles of the sensory epithelium of the cochlear duct and the vestibular end organs at GW11. Immunostaining was limited to hair cells of the organ of Corti by GW12. TAK1 was immune positive in inner hair cells of the organ of Corti by GW12 and colocalized with p75 neurotrophic receptor expression. Expression for SOX2 was confined primarily to the supporting cells of utricle at the earliest stage examined at GW9. Intense expression for GATA3 was presented in the cochlear sensory epithelium and spiral ganglia at GW9. Expression of GATA3 was present along the midline of both the utricle and saccule in the zone corresponding to the striolar reversal zone where the hair cell phenotype switches from type I to type II. The spatiotemporal gradient of the development of the organ of Corti was also evident with the apex of the cochlea forming by GW16. It seems that highly specific staining patterns of several transcriptions factors are critical in guiding the genesis of the inner ear over development. Our findings suggest that the spatiotemporal gradient in cochlear development extends at least until gestational week 16.


Cells ◽  
2019 ◽  
Vol 8 (10) ◽  
pp. 1266 ◽  
Author(s):  
Eszter Berekméri ◽  
Ádám Fekete ◽  
László Köles ◽  
Tibor Zelles

Exploring the development of the hearing organ helps in the understanding of hearing and hearing impairments and it promotes the development of the regenerative approaches-based therapeutic efforts. The role of supporting cells in the development of the organ of Corti is much less elucidated than that of the cochlear sensory receptor cells. The use of our recently published method of single-cell electroporation loading of a fluorescent Ca2+ probe in the mouse hemicochlea preparation provided an appropriate means to investigate the Deiters’ cells at the subcellular level in two different cochlear turns (apical, middle). Deiters’ cell’s soma and process elongated, and the process became slimmer by maturation without tonotopic preference. The tonotopically heterogeneous spontaneous Ca2+ activity less frequently occurred by maturation and implied subcellular difference. The exogenous ATP- and UTP-evoked Ca2+ responses were maturation-dependent and showed P2Y receptor dominance in the apical turn. By monitoring the basic structural dimensions of this supporting cell type as well as its spontaneous and evoked purinergic Ca2+ signaling in the hemicochlea preparation in different stages in the critical postnatal P5-25 developmental period for the first time, we showed that the soma and the phalangeal process of the Deiters’ cells go through age- and tonotopy-dependent changes in the morphometric parameters and purinergic signaling.


2017 ◽  
Vol 114 (21) ◽  
pp. E4271-E4280 ◽  
Author(s):  
Jianguo Fan ◽  
Li Jia ◽  
Yan Li ◽  
Seham Ebrahim ◽  
Helen May-Simera ◽  
...  

The polycistronic miR-183/96/182 cluster is preferentially and abundantly expressed in terminally differentiating sensory epithelia. To clarify its roles in the terminal differentiation of sensory receptors in vivo, we deleted the entire gene cluster in mouse germline through homologous recombination. The miR-183/96/182 null mice display impairment of the visual, auditory, vestibular, and olfactory systems, attributable to profound defects in sensory receptor terminal differentiation. Maturation of sensory receptor precursors is delayed, and they never attain a fully differentiated state. In the retina, delay in up-regulation of key photoreceptor genes underlies delayed outer segment elongation and possibly mispositioning of cone nuclei in the retina. Incomplete maturation of photoreceptors is followed shortly afterward by early-onset degeneration. Cell biologic and transcriptome analyses implicate dysregulation of ciliogenesis, nuclear translocation, and an epigenetic mechanism that may control timing of terminal differentiation in developing photoreceptors. In both the organ of Corti and the vestibular organ, impaired terminal differentiation manifests as immature stereocilia and kinocilia on the apical surface of hair cells. Our study thus establishes a dedicated role of the miR-183/96/182 cluster in driving the terminal differentiation of multiple sensory receptor cells.


2000 ◽  
Vol 201 (6) ◽  
pp. 467-473 ◽  
Author(s):  
M. Matsuoka ◽  
Junko Yoshida-Matsuoka ◽  
Richard M. Costanzo ◽  
Masumi Ichikawa

1974 ◽  
Vol 22 (3) ◽  
pp. 263 ◽  
Author(s):  
DE Hollis ◽  
AG Lyne

The innervation of the mystacial vibrissa follicles in the adult brush-tailed possum, T. vulpecula, has been studied by light and electron microscopy. One to five large nerve trunks penetrate the lower part of the follicle capsule and divide many times as they ascend and completely envelop the con- nective tissue sheath of the follicle. As many as 500 myelinated nerves have been observed in the mid region of the largest follicles. Above the mid region, most of the nerves move closer to the centre of the follicle and finally terminate within or near the outer layer of epithelial cells. Four main types of nerve endings have been observed: (1) Sensory receptor cells, called Merkel cells, with their associated neurites are numerous within the outer layer of epithelial cells. (2) Palisade endings, which are less common than the Merkel cell-neurite complexes, surround the upper part of the glassy membrane of the follicle. In transverse section each palisade ending appears as a flattened central neurite partially enveloped on either side by Schwann cell processes. (3) Bulbous endings occur in both the connective tissue sheath and in the outer layer of follicle epithelial cells. They are larger than types (1) and (2) and their ultrastructure varies markedly. (4) Compound endings occur within the connective tissue sheath of the follicle. They are uncommon but large and are composed of a chain of bulbous units joined by nerves; the entire ending may be encapsulated. Within each unit there is a tangle of nerve fibres. The Merkel cell-neurite complexes and the palisade endings in T. vulpecula are remarkably similar to those of eutherian mammals, suggesting that such sensory structures were features of primitive mammals.


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