Electron-microscopic Study of the Vestibular Dark Cells in the Crista Ampullaris of the Guinea Pig

Kawamata, Seiichi; Harada, Yasuo; Tagashira, Nobuharu

doi:10.3109/00016488609108662

Cited by 9 publications

(4 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The localization of Na+,K+-ATPase activity in dark cell basolateral membranes may support the hypothesis that these cells are involved in endolymph formation (Burnham and Stirling, 1984). Such a role was also suggested by other authors (Dohlman, 1964;Kimura et al, 1964;Nakai and Hilding, 1968;Kimura, 1969;Kawamata et al, 1986).…”

Section: Discussionsupporting

confidence: 82%

Ultrastructural study of the semicircular canal cells of the frog Rana esculenta

1988

View full text Add to dashboard Cite

The ultrastructure of the nonsensory cells (dark cells, transitional cells, and undifferentiated cells) of the frog semicircular canal was studied by using transmission electron microscopy in an attempt to correlate the structure with the functions of these epithelial cells. All the nonsensory cells were linked by tight junctions and desmosomes; this suggested that there is little paracellular ionic transport from perilymph to endolymph. In the dark cell epithelium, the apical intercellular spaces were dilated; in the basal part, numerous basolateral plasma membrane infoldings, containing mitochondria, delimited electron-lucent spaces. The undifferentiated cells and the transitional cells were devoid of any basal membrane infolding. Surrounding the semicircular canal, very flattened and interdigitated mesothelial cells constituted a thin multilayer tissue which limited the perilymphatic space. The morphological aspect of the dark cells suggests that they may play a role in the secretion and/or in the reabsorption of endolymph, which bathes the apical pole of these cells. The undifferentiated and transitional cells can play a role in the maintenance of the endolymphatic ionic composition because of their apical tight junctions and desmosomes.

show abstract

Section: Discussionsupporting

confidence: 82%

Ultrastructural study of the semicircular canal cells of the frog Rana esculenta

1988

View full text Add to dashboard Cite

show abstract

“…On the luminal surface are unique meshwork structures composed of cytoplasmic processes in a reticular arrangement. Based on their findings in guinea pigs, Kawamata et al proposed involvement in the metabolism of otoconia and fluid transport 7 . Interestingly, these basolateral infoldings are closely interwoven with melanocyte processes.…”

Section: Histological Characteristicsmentioning

confidence: 99%

Stria vascularis and vestibular dark cells: characterisation of main structures responsible for inner-ear homeostasis, and their pathophysiological relations

Ciuman

2008

J. Laryngol. Otol.

View full text Add to dashboard Cite

The regulation of inner-ear fluid homeostasis, with its parameters volume, concentration, osmolarity and pressure, is the basis for adequate response to stimulation. Many structures are involved in the complex process of inner-ear homeostasis. The stria vascularis and vestibular dark cells are the two main structures responsible for endolymph secretion, and possess many similarities. The characteristics of these structures are the basis for regulation of inner-ear homeostasis, while impaired function is related to various diseases. Their distinct morphology and function are described, and related to current knowledge of associated inner-ear diseases. Further research on the distinct function and regulation of these structures is necessary in order to develop future clinical interventions.

show abstract

“…Mammalian vestibular endolymph is also characterized by a high potassium concentration. It has been posturated that the ''dark cells'' of utriculus and ampullae are engaged in the production and ionic regulation of vestibular endolymph (Nakai and Hilding, 1968;Kimura, 1969;Kawamata et al, 1986). The dark cells have numerous vacuoles and mitochondria as well as well-developed basal infoldings, which are general cytological features of fluid-transporting cells.…”

mentioning

confidence: 99%

Meshwork arrangement of mitochondria-rich, Na+,K+-ATPase-rich cells in the saccular epithelium of rainbow trout (Oncorhynchus mykiss) inner ear

Takagi

1997

Anat. Rec.

View full text Add to dashboard Cite

Background Electrolyte composition of the teleost fish inner ear endolymph is characterized by a high potassium concentration. From the ultrastructural characteristics, the mitochondria‐rich cells (MRCs) in the inner ear epithelium are suggested to regulate the ionic composition of the endolymph. Methods In the present study, the ultrastructure of MRCs in the saccular epithelium of the rainbow trout (Onchorhynchus mykiss) was studied, and the immunocytochemical detection of Na+,K+‐ATPase, the key enzyme of the ion‐transport, in the saccular epithelium was conducted. Electrolyte composition of the saccular endolymph was also determined. Results Electron‐microscopic observations revealed that MRCs located at the periphery of the sensory macula have numerous elongated mitochondria and a well‐developed tubular system. Immunocytochemical detection of Na+,K+‐ATPase on paraffin sections showed that immunoreactive (ir‐) cells were distributed specifically around the sensory macula. Judging from their shape, size, and localization, the Na+,K+‐ATPase ir‐cells corresponded to the MRCs. The whole‐mount immunocytochemistry using Na+,K+‐ATPase as a marker for the MRC revealed that MRCs were connected with one another by extended cellular processes, and thus forming a dense meshwork structure around the macula. In the endolymph, potassium levels were 13 times higher than those in plasma, chloride levels were slightly higher whereas sodium, calcium, magnesium, and phosphate levels were lower. Conclusions Thus, the saccular MRCs abundant in Na+,K+‐ATPase are distributed around the sensory macula forming a dense meshwork structure, with the suggested function to regulate the electrolyte composition of the saccular endolymph. Anat. Rec. 248:483‐489, 1997. © 1997 Wiley‐Liss, Inc.

show abstract

Electron-microscopic Study of the Vestibular Dark Cells in the Crista Ampullaris of the Guinea Pig

Cited by 9 publications

References 13 publications

Ultrastructural study of the semicircular canal cells of the frog Rana esculenta

Ultrastructural study of the semicircular canal cells of the frog Rana esculenta

Stria vascularis and vestibular dark cells: characterisation of main structures responsible for inner-ear homeostasis, and their pathophysiological relations

Meshwork arrangement of mitochondria-rich, Na+,K+-ATPase-rich cells in the saccular epithelium of rainbow trout (Oncorhynchus mykiss) inner ear

Contact Info

Product

Resources

About