Horseradish Peroxidase Permeation from the Capillaries of the Stria Vascularis after Inoculation of Endotoxin into the Middle Ear

Escherichia coli-derived endotoxin was inoculated in the middle ear of guinea pigs 24 hours after being injected intraperitoneally. Twenty-four hours after the middle ear inoculation, horseradish peroxidase (HRP) was injected via the femoral vein and the permeability of HRP through the capillaries of the stria vascularis and the destination of the leaked HRP were examined. A large amount of HRP leaked out of the capillary through the opened endothelial cell junctions and penetrated the enlarged intercellular spaces. Leaked HRP entered the pinocytotic vesicles of the intermediate cells. Even slightly degenerated intermediate cells retained this function. The HRP penetrated the spongelike structure of the marginal cells leading to the intercellular space. This structure was not observed without endotoxin. The HRP could not pass to the cochlear duct through the tight junctions between marginal cells. Blood sludging was observed in the strial capillaries. It appeared more frequently in the upper three turns than in the basal turn. The HRP leakage out of the capillaries was observed not only in the upper three turns but also in the basal turn.

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Another role for melanocytes: their importance for normal stria vascularis development in the mammalian inner ear

Development ◽

10.1242/dev.107.3.453 ◽

1989 ◽

Vol 107 (3) ◽

pp. 453-463 ◽

Cited By ~ 12

Author(s):

K.P. Steel ◽

C. Barkway

Keyword(s):

Neural Crest ◽

Basal Cell ◽

Stria Vascularis ◽

Normal Adult ◽

Basal Cells ◽

Cochlear Duct ◽

Cell Layers ◽

Marginal Cells ◽

Intermediate Cells ◽

And Function

The stria vascularis of the mammalian cochlea is composed primarily of three types of cells. Marginal cells line the lumen of the cochlear duct and are of epithelial origin. Basal cells also form a continuous layer and they may be mesodermal or derived from the neural crest. Intermediate cells are melanocyte-like cells, presumably derived from the neural crest, and are scattered between the marginal and basal cell layers. The marginal cells form extensive interdigitations with the basal and intermediate cells in the normal adult stria. The stria also contains a rich supply of blood vessels. We investigated the role of melanocytes in the stria vascularis by studying its development in a mouse mutant, viable dominant spotting, which is known to have a primary neural crest defect leading to an absence of recognisable melanocytes in the skin. Melanocytes were not found in the stria of most of the mutants examined, and from about 6 days of age onwards a reduced amount of interdigitation amongst the cells of the stria was observed. These ultrastructural anomalies were associated with strial dysfunction. In the normal adult mammal, the stria produces an endocochlear potential (EP), a resting dc potential in the endolymph in the cochlear duct, which in mice is normally about +100 mV. In our control mice, EP rose to adult levels between 6 and 16 days after birth. In most of the mutants we studied, EP was close to zero at all ages from 6 to 20 days. Melanocyte-like cells appear to be vital for normal stria vascularis development and function. They may be necessary to facilitate the normal process of interdigitation between marginal and basal cell processes at a particular stage during development, and the lack of adequate interdigitation in the mutants may be the cause of their strial dysfunction. Alternatively, melanocytes may have some direct, essential role in the production of an EP by the stria. Melanocytes may be important both for normal strial development and for the production of the EP. We believe this is the clearest demonstration yet of a role for migratory melanocytes other than their role in pigmentation.

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

AJP Cell Physiology ◽

10.1152/ajpcell.00312.2001 ◽

2002 ◽

Vol 282 (2) ◽

pp. C403-C407 ◽

Cited By ~ 210

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.

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The Morphologic Effects of Histamine on the Lateral Cochlear Wall

Otolaryngology ◽

10.1177/019459987908700523 ◽

1979 ◽

Vol 87 (5) ◽

pp. 666-684 ◽

Cited By ~ 2

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.

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Stria Ultrastructure and Vessel Transport in Acoustic Trauma

Annals of Otology Rhinology & Laryngology ◽

10.1177/000348947408300413 ◽

1974 ◽

Vol 83 (4) ◽

pp. 498-514 ◽

Cited By ~ 43

Author(s):

Arndt J. Duvall ◽

W. Dixon Ward ◽

Kathryn E. Lauhala

Keyword(s):

Horseradish Peroxidase ◽

Stria Vascularis ◽

Membrane System ◽

Acoustic Trauma ◽

Consistent Pattern ◽

The Other ◽

Intravenous Injections ◽

Significant Damage ◽

Intermediate Cells ◽

Ultrastructural Abnormality

One hundred and ten chinchillas were exposed to a 700–2800 Hz noise at 123 dB for 15 minutes. A consistent pattern of ultrastructural pathology within the lateral cochlear wall was found. Significant damage to the stria vascularis was first observed one hour postexposure, reached a peak at 24 hours, and had recovered almost completely by 28 days. Spiral prominence damage was permanent. The pathology included stria widening, temporary disappearance of intermediate cells, alterations of the internal membrane system and abnormal vessel transport. Horseradish peroxidase (HRP) was employed as an indicator of transport from vessels. Transport from the stria vessels was absent when stria ultrastructural abnormality was at a maximum; at other postexposure times, however, abnormally rapid exodus of HRP from the vessels of the stria was observed in animals who had received intravenous injections of HRP 30 seconds prior to sacrifice. On the other hand, no leakage was observed in the animals injected one minute before sacrifice. Theories to explain this transport dichotomy are proposed.

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MRL/MP-lpr/lpr Mouse as a Model of Immune-Induced Sensorineural Hearing Loss

Annals of Otology Rhinology & Laryngology ◽

10.1177/0003489492101s1017 ◽

1992 ◽

Vol 101 (10_suppl) ◽

pp. 82-86 ◽

Cited By ~ 42

Author(s):

Chikashi Kusakari ◽

Koji Hozawa ◽

Masahisa Kyogoku ◽

Shuji Koike ◽

Tomonori Takasaka

Keyword(s):

Hearing Loss ◽

Sensorineural Hearing Loss ◽

Stria Vascularis ◽

Sensorineural Hearing ◽

Response Threshold ◽

Auditory Brain Stem Response ◽

Auditory Brain Stem ◽

Hearing Acuity ◽

Marginal Cells ◽

Intermediate Cells

Hearing acuity and inner ear disorders of MRL/ lpr mice, bred for the study of autoimmune disease, were examined in comparison to those of BALB/c mice. The auditory brain stem response threshold of 20-week-old MRL/ lpr mice was significantly higher than that of BALB/c mice of the same age (p < .01). The pathologic changes of 20-week-old MRL/ lpr mice were characterized by the degeneration of intermediate cells, widened intercellular spaces, and immunoglobulin G deposition on the basement membrane of strial blood vessels as well as in the basal infolding of strial marginal cells, which were absent in BALB/c mice. That there were no other evident pathologic findings in the cochlea or middle ear suggests that these changes in the stria vascularis seemed to be responsible for the sensorineural hearing loss of this mouse. The MRL/ lpr mouse was thought to be a good experimental model to study the spontaneous sensorineural hearing loss caused by an immune reaction.

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Two types of K+ currents in marginal cells cultured from rat stria vascularis

Hearing Research ◽

10.1016/s0378-5955(97)00120-2 ◽

1997 ◽

Vol 112 (1-2) ◽

pp. 186-198 ◽

Cited By ~ 1

Author(s):

Sang Jeong Kim ◽

Steven K. Juhn

Keyword(s):

Stria Vascularis ◽

Marginal Cells ◽

K Currents ◽

Cells Cultured

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Ultrastructural Characteristics of Capillaries Entering and Leaving the Stria Vascularis

Annals of Otology Rhinology & Laryngology ◽

10.1177/000348948609500320 ◽

1986 ◽

Vol 95 (3) ◽

pp. 309-312 ◽

Cited By ~ 7

Author(s):

Kensuke Watanabe

Keyword(s):

Horseradish Peroxidase ◽

Basal Cell ◽

Stria Vascularis ◽

The Other ◽

Spiral Ligament ◽

Perivascular Spaces ◽

Basal Cells ◽

Vascular Flow ◽

Cell Layers ◽

Ultrastructural Characteristics

Capillaries entering and leaving the stria vascularis were surrounded by layers of basal cells and fibrocytes. The entering capillaries were surrounded by one or two thin basal cells, while the leaving capillaries were surrounded by four or five thicker and interdigitated basal cell layers. Moreover, the layers surrounding the leaving capillaries persisted further into the spiral ligament. Two kinds of filaments were observed in the basal cells, one thin and the other thick. Capillaries were observed to leak horseradish peroxidase before they entered and after they left the stria vascularis. Although the reaction product of horseradish peroxidase was observed in all perivascular spaces of leaving capillaries, very little or no reaction product was observed around some entering capillaries. It is speculated that the layers of basal cells and fibrocytes around entering and leaving capillaries control the vascular flow out of the stria vascularis, although the layers around leaving capillaries may be more contractile than those around entering capillaries.

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THE FATE OF EXOGENOUS PEROXIDASE IN THE THYMUS OF NEWBORN AND YOUNG ADULT MICE

Journal of Histochemistry & Cytochemistry ◽

10.1177/20.6.445 ◽

1972 ◽

Vol 20 (6) ◽

pp. 445-462 ◽

Cited By ~ 4

Author(s):

SUSAN WINTER GERVIN ◽

ERIC HOLTZMAN

Keyword(s):

Young Adult ◽

Horseradish Peroxidase ◽

Blood Vessels ◽

Blood Stream ◽

Active Uptake ◽

Adult Mice ◽

Pinocytotic Vesicles ◽

Parenchymal Cells ◽

Shed Light

Horseradish peroxidase injected intraperitoneally into newborn and young adult mice is subsequently found in the thymus within the lumina of blood vessels and in perivascular areas. In the newborns, much peroxidase is also detectable throughout the thymic parenchyma; it is present in extracellular spaces and in pinocytotic vesicles and lysosomes in thymocytes and other parenchymal cells. In young adult mice, very little peroxidase escapes from the vicinity of blood vessels; cells resembling macrophages contain most of the tracer present outside of blood vessels and only those thymocytes located very near small venules or capillaries are exposed to peroxidase. The results suggest that the "blood-thymic" barrier is not simply a static set of structures that prevents penetration of potential antigens from the blood stream into the parenchyma; in young adult animals, active uptake of foreign molecules by macrophages and other cells is an important component of the barrier. In addition, the findings may shed light on aspects of the development of the immunologic system, since it appears, for example, that potential antigens can interact directly with far more cells in the newborn thymus than is true in the adult.

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