Gastric type H+,K+-ATPase in the cochlear lateral wall is critically involved in formation of the endocochlear potential

2006 ◽  
Vol 291 (5) ◽  
pp. C1038-C1048 ◽  
Author(s):  
Toshiaki Shibata ◽  
Hiroshi Hibino ◽  
Katsumi Doi ◽  
Toshihiro Suzuki ◽  
Yasuo Hisa ◽  
...  
Keyword(s):  
Stria Vascularis ◽  
Critical Role ◽  
Specific Inhibitor ◽  
Lateral Wall ◽  
Endocochlear Potential ◽  
Pcr Analysis ◽  
Spiral Ligament ◽  
Gastric Type ◽  
Marginal Cells ◽  
Strong Immunoreactivity

Cochlear endolymph has a highly positive potential of approximately +80 mV known as the endocochlear potential (EP). The EP is essential for hearing and is maintained by K+ circulation from perilymph to endolymph through the cochlear lateral wall. Various K+ transport apparatuses such as the Na+,K+-ATPase, the Na+-K+-2Cl− cotransporter, and the K+ channels Kir4.1 and KCNQ1/KCNE1 are expressed in the lateral wall and are known to play indispensable roles in cochlear K+ circulation. The gastric type of the H+,K+-ATPase was also shown to be expressed in the cochlear lateral wall (Lecain E, Robert JC, Thomas A, and Tran Ba Huy P. Hear Res 149: 147–154, 2000), but its functional role has not been well studied. In this study we examined the precise localization of H+,K+-ATPase in the cochlea and its involvement in formation of EP. RT-PCR analysis showed that the cochlea expressed mRNAs of gastric α1-, but not colonic α2-, and β-subunits of H+,K+-ATPase. Immunolabeling of an antibody specific to the α1 subunit was detected in type II, IV, and V fibrocytes distributed in the spiral ligament of the lateral wall and in the spiral limbus. Strong immunoreactivity was also found in the stria vascularis. Immunoelectron microscopic examination exhibited that the H+,K+-ATPase was localized exclusively at the basolateral site of strial marginal cells. Application of Sch-28080, a specific inhibitor of gastric H+,K+-ATPase, to the spiral ligament as well as to the stria vascularis caused prominent reduction of EP. These results may imply that the H+,K+-ATPase in the cochlear lateral wall is crucial for K+ circulation and thus plays a critical role in generation of EP.

Distribution and significance of endothelin 1 in guinea pig cochlear lateral wall

2007 ◽  
Vol 121 (8) ◽  
pp. 721-724 ◽  
Author(s):  
D-Y Xu ◽  
Y-D Tang ◽  
S-X Liu ◽  
J Liu
Keyword(s):  
Guinea Pig ◽  
Stria Vascularis ◽  
Lateral Wall ◽  
Complex Method ◽  
Spiral Ligament ◽  
Basal Cells ◽  
Endothelin 1 ◽  
Marginal Cells ◽  
Spiral Ligament Fibrocytes ◽  
Avidin Biotin Complex

AbstractEndothelin 1 is a vasoconstrictive peptide with many biological functions. To investigate the distribution of endothelin 1 in guinea pig cochlear lateral wall and the significance of endothelin 1 in maintaining cochlear homeostasis, the immunohistochemistry avidin biotin complex method was applied by using rabbit anti-endothelin 1 polyclonal antibody as primary antibody. Endothelin-1-like activities were detected in the marginal cells, spiral prominence epithelial cells, outer sulcus cells, stria vascularis capillaries, basal cells and spiral ligament fibrocytes.These results suggest that endothelin 1 may play an important role in maintaining cochlear homeostasis.

scholarly journals Expression of Gap Junction Protein Connexin43 in the Adult Rat Cochlea: Comparison with Connexin26

2003 ◽  
Vol 51 (7) ◽  
pp. 903-912 ◽  
Author(s):  
Toshihiro Suzuki ◽  
Tetsuro Takamatsu ◽  
Masahito Oyamada
Keyword(s):  
Gap Junction ◽  
Stria Vascularis ◽  
Three Dimensional ◽  
Organ Of Corti ◽  
Structural Difference ◽  
Lateral Wall ◽  
Spiral Ligament ◽  
Adult Rat ◽  
Junction Protein ◽  
Rat Cochlea

To elucidate whether the two different gap junction proteins connexin43 (Cx43) and connexin26 (Cx26) are expressed and localized in a similar manner in the adult rat cochlea, we performed three-dimensional confocal microscopy using cryosections and surface preparations. In the cochlear lateral wall, Cx43-positive spots were localized mainly in the stria vascularis and only a few spots were present in the spiral ligament, whereas Cx26-positive spots were detected in both the stria vascularis and the spiral ligament. In the spiral limbus, Cx43 was widely distributed, whereas Cx26 was more concentrated on the side facing the scala vestibuli and in the basal portion. In the organ of Corti, Cx43-positive spots were present between the supporting cells but they were fewer and much smaller than those of Cx26. These data demonstrated distinct differences between Cx43 and Cx26 in expression and localization in the cochlea. In addition, the area of overlap of zonula occludens-1 (ZO-1) immunolabeling with Cx43-positive spots was small, whereas it was fairly large with Cx26-positive spots in the cochlear lateral wall, suggesting that the differences are not associated with the structural difference between carboxyl terminals, i.e., those of Cx43 possess sequences for binding to ZO-1, whereas those of Cx26 lack these binding sequences.

KCNJ10 (Kir4.1) potassium channel knockout abolishes endocochlear potential

2002 ◽  
Vol 282 (2) ◽  
pp. C403-C407 ◽  
Author(s):  
Daniel C. Marcus ◽  
Tao Wu ◽  
Philine Wangemann ◽  
Paulo Kofuji
Keyword(s):  
Driving Force ◽  
Stria Vascularis ◽  
Endocochlear Potential ◽  
Sensory Transduction ◽  
Basal Cells ◽  
Transport Pathways ◽  
Main Charge ◽  
Marginal Cells ◽  
Intermediate Cells ◽  
Two Barriers

Stria vascularis of the cochlea generates the endocochlear potential and secretes K+. K+ is the main charge carrier and the endocochlear potential the main driving force for the sensory transduction that leads to hearing. Stria vascularis consists of two barriers, marginal cells that secrete potassium and basal cells that are coupled via gap junctions to intermediate cells. Mice lacking the KCNJ10 (Kir4.1) K+ channel in strial intermediate cells did not generate an endocochlear potential. Endolymph volume and K+ concentration ([K+]) were reduced. These studies establish that the KCNJ10 K+ channel provides the molecular mechanism for generation of the endocochlear potential in concert with other transport pathways that establish the [K+] difference across the channel. KCNJ10 is also a limiting pathway for K+ secretion.

The morphological and functional development of the stria vascularis in miniature pigs

2017 ◽  
Vol 29 (3) ◽  
pp. 585 ◽  
Author(s):  
Weiwei Guo ◽  
Haijin Yi ◽  
Zhang Yan ◽  
Lili Ren ◽  
Lei Chen ◽  
...  
Keyword(s):  
Animal Studies ◽  
Stria Vascularis ◽  
Organ Of Corti ◽  
Lateral Wall ◽  
Cell Types ◽  
Endocochlear Potential ◽  
Miniature Pigs ◽  
Functional Development ◽  
Transmission Electron ◽  
Different Types

The purpose of this study was to examine the morphological and functional development of the lateral wall of the scala media of the cochlea in miniature pigs; light and transmission electron microscopy and electrophysiology were used for this purpose. We showed that the lateral wall of the scala media of the cochlea appears at embryonic Day 21 (E21) when the cochlear duct begins to form. From E28 to E49, the lateral wall can be distinguished according to its position along the cochlea. At E56, cells in the lateral wall begin to differentiate into three different types. At E70, three cell types, marginal, intermediate and basal, can be clearly distinguished. At E91, the stria vascularis is adult-like and the organ of Corti is also morphologically mature. The average endocochlear potential measured from the second turn of the cochlea (at E98, postnatal Day 1 (P1), P13 and P30) was 71.4 ± 2.5 (n = 7), 78.8 ± 1.5 (n = 10), 77.3 ± 2.3 (n = 10) and 78.0 ± 2.1 mV (n = 10), respectively. Our results suggest that in miniature pigs the stria vascularis develops during the embryonic period, concurrent with maturation of the organ of Corti. The magnitude of the endocochlear potential reached its mature level when the stria vascularis was morphologically adult-like at E98. These findings provide a morphological and functional basis for future animal studies using the miniature pig model concerning the pathogenesis of various inner-ear diseases.

Positive endocochlear potential: Mechanism of production by marginal cells of stria vascularis

1987 ◽  
Vol 29 (2-3) ◽  
pp. 117-124 ◽  
Author(s):  
Franklin F. Offner ◽  
Peter Dallos ◽  
Mary Ann Cheatham
Keyword(s):  
Stria Vascularis ◽  
Endocochlear Potential ◽  
Potential Mechanism ◽  
Marginal Cells

Membranous Cytoplasmic Bodies in the Lateral Wall of the Cat Cochlea

1992 ◽  
Vol 101 (4) ◽  
pp. 355-359 ◽  
Author(s):  
Kensuke Watanabe ◽  
Atsushi Komatsuzaki
Keyword(s):  
Stria Vascularis ◽  
Lateral Wall ◽  
Spiral Ligament ◽  
Phagocytic Function ◽  
The Core ◽  
Cytoplasmic Bodies ◽  
Dense Bodies ◽  
Intermediate Cells

Membranous cytoplasmic bodies (MCBs) were observed both in the intermediate cells of the stria vascularis and in the fibrocytes of the spiral ligament in normal cats. The MCBs in the intermediate cells were round or ovoid, ranged from 1 to 5 μm in diameter, and consisted of 2 to 40 or more layers disposed concentrically about a core. The core was composed of not only cytoplasm but also of mitochondria in various stages of disintegration, empty vacuoles, and many kinds of dense bodies similar to lysosomes. The MCBs in the fibrocytes were similar to those in the intermediate cells, but they were a little smaller in diameter and consisted of fewer than 10 layers. Both in the intermediate cells and in the fibrocytes, MCBs seem to have a phagocytic function.

The Morphologic Effects of Histamine on the Lateral Cochlear Wall

1979 ◽  
Vol 87 (5) ◽  
pp. 666-684 ◽  
Author(s):  
Arndt J. Duvall ◽  
Margaret J. Hukee ◽  
Peter A. Santi
Keyword(s):  
Stria Vascularis ◽  
Spiral Ligament ◽  
Glycogen Depletion ◽  
Intercellular Spaces ◽  
Pore System ◽  
Vessel Permeability ◽  
Dependent Change ◽  
Mode Of Transport ◽  
Marginal Cells ◽  
Dose Dependent

The chinchilla lateral cochlear wall (stria vascularis, spiral ligament, and spiral prominence) was examined by morphologic and histochemical techniques following various doses of intravenous histamine. The three main findings were as follows: (1) the basic ultrastructure was not altered by histamine; (2) there is a time- and dose-dependent change in the rate of stria vascularis vessel permeability to a small protein tracer (horseradish peroxidase), but the mode of transport (large pore system) is unchanged; and (3) glycogen depletion in stria marginal cells occurs with its apparent mobilization into stria intercellular spaces.

scholarly journals Quantitative immunocytochemical localization of Na+,K+-ATPase alpha-subunit in the lateral wall of rat cochlear duct.

1989 ◽  
Vol 37 (3) ◽  
pp. 353-363 ◽  
Author(s):  
T Iwano ◽  
A Yamamoto ◽  
K Omori ◽  
M Akayama ◽  
T Kumazawa ◽  
...  
Keyword(s):  
Plasma Membranes ◽  
Rat Kidney ◽  
Stria Vascularis ◽  
Basolateral Membrane ◽  
Lateral Wall ◽  
Alpha Subunit ◽  
Membrane Domain ◽  
Cochlear Duct ◽  
Gold Particles ◽  
Marginal Cells

Ultrastructural localization of the alpha-subunit of Na+,K+-ATPase on the lateral wall of rat cochlear duct was investigated quantitatively by the protein A-gold method, using affinity-purified antibody against the alpha-subunit of rat kidney Na+,K+-ATPase. In the stria vascularis, gold particles were sparse over the endolymphatic luminal surface of the marginal cells but were numerous over the basolateral membrane. The labeling density of the basolateral membrane was almost equal to that of the same domain of the distal tubule cells of kidney. The intermediate cells were studded with a large number of gold particles on the plasma membrane domain facing the basolateral domain of the marginal cells. On the luminal surfaces of the other epithelial cells, including those of Reissner's membrane, no significant amount of gold particles was found. Many gold particles were localized on all the plasma membranes of the spiral prominence stromal cells and on the intracellular membrane domain of the external sulcus cells.

Location and function of the epithelial Na channel in the cochlea

2001 ◽  
Vol 280 (2) ◽  
pp. F214-F222 ◽  
Author(s):  
Vincent Couloigner ◽  
Michel Fay ◽  
Sabri Djelidi ◽  
Nicolette Farman ◽  
Brigitte Escoubet ◽  
...  
Keyword(s):  
Stria Vascularis ◽  
Spiral Ganglion ◽  
Endocochlear Potential ◽  
Na Channel ◽  
Spiral Ligament ◽  
Α Subunit ◽  
Subunit Mrna ◽  
Spiral Limbus ◽  
Epithelial Na Channel

In the cochlea, endolymph is a K-rich and Na-poor fluid. The purpose of the present study was to check the presence and to assess the role of epithelial Na channel (ENaC) in this organ. α-, β-, and γ-ENaC subunit mRNA, and proteins were detected in rat cochlea by RT-PCR and Western blot. α-ENaC subunit mRNA was localized by in situ hybridization in both epithelial (stria vascularis, spiral prominence, spiral limbus) and nonepithelial structures (spiral ligament, spiral ganglion). The α-ENaC-positive tissues were also positive for β-subunit mRNA (except spiral ganglion) or for γ-subunit mRNA (spiral limbus, spiral ligament, and spiral ganglion), but the signals of β- and γ-subunits were weaker than those observed for α-subunit. In vivo, the endocochlear potential was recorded in guinea pigs under normoxic and hypoxic conditions after endolymphatic perfusion of ENaC inhibitors (amiloride, benzamil) dissolved either in K-rich or Na-rich solutions. ENaC inhibitors altered the endocochlear potential when Na-rich but not when K-rich solutions were perfused. In conclusion, ENaC subunits are expressed in epithelial and nonepithelial cochlear structures. One of its functions is probably to maintain the low concentration of Na in endolymph.

Long-Term Changes in Off-Lesion Endocochlear Potential after Induction of Localized Lesions in the Lateral Wall

2001 ◽  
Vol 110 (3) ◽  
pp. 271-276 ◽  
Author(s):  
Rong Wu ◽  
Tomoyuki Hoshino
Keyword(s):  
Stria Vascularis ◽  
Green Light ◽  
Lateral Wall ◽  
Sudden Hearing Loss ◽  
Endocochlear Potential ◽  
Light Illumination ◽  
Morphological Examination ◽  
Damage Repair ◽  
Low Tone ◽  
Experimental Values

Localized lesions were produced in various turns of the guinea pig cochlea by means of a photochemical reaction between systemically administered rose bengal dye and green light illumination. The endocochlear potential (EP) was measured at various off-lesion sites, and a morphological examination was performed. In a previous study, this same investigation was done at 3 days, at which time all sites apical to the lesion showed significant EP depression, and damage to the stria vascularis at the lesion was ongoing. In the present 2-week study, the apical EP values were not different from the basal values, and all experimental values were essentially the same as the EP values found in control animals. Morphological examination revealed that the previously damaged structures were greatly repaired. Localized damage and early apical EP depression followed by damage repair and eventual EP recovery could account for the clinical course of certain cases of idiopathic sudden hearing loss involving low-tone deafness.

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