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1.
HNO ; 2024 Apr 09.
Article de Allemand | MEDLINE | ID: mdl-38592481

RÉSUMÉ

BACKGROUND: Results of neurotological function diagnostics in the context of interdisciplinary vertigo assessment are usually formulated as free-text reports (FTR). These are often subject to high variability, which may lead to loss of information. The aim of the present study was to evaluate the completeness of structured reports (SR) and referrer satisfaction in the neurotological assessment of vertigo. MATERIALS AND METHODS: Neurotological function diagnostics performed as referrals (n = 88) were evaluated retrospectively. On the basis of the available raw data, SRs corresponding to FTRs from clinical routine were created by means of a specific SR template for neurotological function diagnostics. FTRs and SRs were evaluated for completeness and referring physician satisfaction (n = 8) using a visual analog scale (VAS) questionnaire. RESULTS: Compared to FTRs, SRs showed significantly increased overall completeness (73.7% vs. 51.7%, p < 0.001), especially in terms of patient history (92.5% vs. 66.7%, p < 0.001), description of previous findings (87.5% vs. 38%, p < 0.001), and neurotological (33.5% vs. 26.7%, p < 0.001) and audiometric function diagnostics (58% vs. 32.3%, p < 0.001). In addition, SR showed significantly increased referring physician satisfaction (VAS 8.8 vs. 4.9, p < 0.001). CONCLUSION: Neurotological SRs enable a significantly increased report completeness with higher referrer satisfaction in the context of interdisciplinary assessment of vertigo. Furthermore, SRs are particularly suitable for scientific data analysis, especially in the context of big data analyses.

2.
HNO ; 66(11): 843-846, 2018 Nov.
Article de Allemand | MEDLINE | ID: mdl-30006652

RÉSUMÉ

This article presents the case of a 39-year-old woman receiving injection therapy for cervicalgia. Due to accidental injection into the cervical spinal cord, the patient suffered from syncope, sensomotoric deficit, and bilateral neural hearing loss. Injection therapies for spinal disorders are routinely carried out in clinical practice, despite a low level of evidence and potentially severe complications. In the event of neuro-otologic complications, prompt evaluation by an otologist should be sought and rehabilitation initiated if necessary.


Sujet(s)
Perte auditive soudaine , Cervicalgie , Adulte , Femelle , Surdité bilatérale partielle , Perte auditive soudaine/étiologie , Humains , Injections/effets indésirables , Cervicalgie/thérapie
3.
HNO ; 66(2): 144-147, 2018 Feb.
Article de Allemand | MEDLINE | ID: mdl-28608188

RÉSUMÉ

A 48-year-old female patient presented to the ENT department of the University Medical Center of the Johannes Gutenberg University Mainz with subfebrile temperatures, one-sided nasal obstruction, and left-sided cephalgia. Clinical examination and CT scans showed a mass occupying the left nasal cavity and left paranasal sinuses. Further diagnosis and histopathological examination showed an HIV-associated plasmablastic lymphoma of the left paranasal sinuses. This case report with literature review discusses the diagnosis and treatment of this rare nasal tumor.


Sujet(s)
Infections à VIH , Tumeurs des sinus de la face , Lymphome plasmoblastique , Femelle , Infections à VIH/complications , Humains , Résultats fortuits , Adulte d'âge moyen , Tumeurs des sinus de la face/virologie , Lymphome plasmoblastique/virologie
4.
Neuroscience ; 311: 490-8, 2015 Dec 17.
Article de Anglais | MEDLINE | ID: mdl-26528886

RÉSUMÉ

Gentamicin treatment induces hair cell death or survival in the inner ear. Besides the well-known toxic effects, the phosphatidylinositol-3 kinase/Akt (PI3K/Akt) pathway was found to be involved in cell protection. After gentamicin application, the spatiotemporal expression patterns of Akt and its activated form (p-Akt) were determined in male guinea pigs. A single dose of 0.1 mL gentamicin (4 mg/ear/animal) was intratympanically injected. The auditory brainstem responses (ABRs) were recorded prior to application and 1, 2 and 7 days afterward. At these three time points the cochleae (n=10 in each case) were removed, transferred to fixative and embedded in paraffin. Seven ears were used as untreated controls. Gentamicin, Akt and p-Akt were identified immunohistochemically in various regions of the cochlea and their staining intensities were quantified on sections using digital image analysis. The application of gentamicin resulted in hearing loss with a concomitant up-regulation of Akt-expression in the organ of Corti and spiral ganglion cells and an additional activation in spiral ganglion cells. At the level of individual ears, clear intracellular correlations were found between Akt- and p-Akt-expression in the stria vascularis and interdental cells and, to a minor extent, in the spiral ligament and the organ of Corti. Furthermore, statistical evidence for the connection between gentamicin up-take and hearing loss was detected. The increase in Akt- and p-Akt-expression in the organ of Corti and spiral ganglion cells indicates a selected response of the cochlea against gentamicin toxicity.


Sujet(s)
Agents du système nerveux central/pharmacologie , Cochlée/effets des médicaments et des substances chimiques , Cochlée/physiologie , Gentamicine/pharmacologie , Protéines proto-oncogènes c-akt/métabolisme , Animaux , Seuil auditif/effets des médicaments et des substances chimiques , Seuil auditif/physiologie , Cochlée/cytologie , Potentiels évoqués auditifs du tronc cérébral/effets des médicaments et des substances chimiques , Potentiels évoqués auditifs du tronc cérébral/physiologie , Cochons d'Inde , Immunohistochimie , Mâle
5.
Horm Metab Res ; 45(12): 887-92, 2013 Nov.
Article de Anglais | MEDLINE | ID: mdl-23794402

RÉSUMÉ

Intense noise exposure and the application of ototoxic substances result in increased levels of reactive oxygen species (ROS) and reactive nitrogen species (RNS), such as nitric oxide (NO). In order to reduce the free NO concentration in the inner ear under pathological conditions, the use of natural cytoprotective substances such as 17ß-estradiol is a promising therapeutic concept. In male guinea pigs the organ of Corti and the lateral wall were isolated from the cochlea and afterwards incubated for 6 h in cell-culture medium. 17ß-Estradiol was adjusted in 2 concentrations to organ cultures of the right ears (12 animals per concentration). The left ears were used as controls. The NO production was quantified in the supernatant by chemiluminescence after incubation. Depending on the concentration, 17ß-estradiol reduced NO in the organ of Corti by 43% (p=0.015) and 46% (p=0.026), respectively. In the lateral wall, the NO concentration was reduced by 24%, but without statistical significance (p=0.86). However, when analyzing the association between the 2 cochlear regions for each animal separately, the NO concentrations were lower in nearly all 17ß-estradiol-treated ears compared to controls. In order to demonstrate the flexibility of the organ culture system, the NO donor DETA NONOate and the nitric oxide synthase inhibitors L-NAME and L-NMMA were applied. The electron microscopic analysis revealed a well-preserved cochlear cell morphology after incubation. The ability of 17ß-estradiol to influence the NO production preferentially in the organ of Corti might offer new therapeutic perspectives for inner ear protection.


Sujet(s)
Cochlée/métabolisme , Oestradiol/pharmacologie , Monoxyde d'azote/biosynthèse , Animaux , Forme de la cellule/effets des médicaments et des substances chimiques , Cochlée/cytologie , Cochlée/ultrastructure , Régulation négative/effets des médicaments et des substances chimiques , Cochons d'Inde , Mâle , Nitrites/métabolisme , Techniques de culture d'organes , Régulation positive/effets des médicaments et des substances chimiques
6.
Cell Death Dis ; 1: e51, 2010 Jul 01.
Article de Anglais | MEDLINE | ID: mdl-21364656

RÉSUMÉ

Hearing impairment caused by ototoxic insults, such as noise or gentamicin is a worldwide health problem. As the molecular circuitries involved are not yet resolved, current otoprotective therapies are rather empirical than rational. Here, immunohistochemistry and western blotting showed that the cytoprotective protein survivin is expressed in the human and guinea pig cochlea. In the guinea pig model, moderate noise exposure causing only a temporary hearing impairment transiently evoked survivin expression in the spiral ligament, nerve fibers and the organ of Corti. Mechanistically, survivin upregulation may involve nitric oxide (NO)-induced Akt signaling, as enhanced expression of the endothelial NO synthase and phosphorylated Akt were detectable in some surviving-positive cell types. In contrast, intratympanic gentamicin injection inducing cell damage and permanent hearing loss correlated with attenuated survivin levels in the cochlea. Subsequently, the protective activity of the human and the guinea pig survivin orthologs against the ototoxin gentamicin was demonstrated by ectopic overexpression and RNAi-mediated depletion studies in auditory cells in vitro. These data suggest that survivin represents an innate cytoprotective resistor against stress conditions in the auditory system. The pharmacogenetic modulation of survivin may thus provide the conceptual basis for the rational design of novel therapeutic otoprotective strategies.


Sujet(s)
Cochlée/métabolisme , Protéines IAP/physiologie , Animaux , Cellules cultivées , Cochlée/cytologie , Femelle , Gentamicine/toxicité , Cochons d'Inde , Humains , Protéines IAP/génétique , Protéines IAP/métabolisme , Mâle , Monoxyde d'azote/métabolisme , Nitric oxide synthase type III/métabolisme , Phosphorylation , Protéines proto-oncogènes c-akt/métabolisme , Interférence par ARN , Transduction du signal , Survivine , Régulation positive
7.
HNO ; 57(4): 339-44, 2009 Apr.
Article de Allemand | MEDLINE | ID: mdl-19148615

RÉSUMÉ

BACKGROUND: The protective effect of ascorbic acid against noise-induced hearing loss and increased nitric oxide (NO) formation after noise exposure have already been demonstrated in animal models. However, the influence of ascorbic acid on noise-induced NO production within the cochlea is still unclear. METHODS: Guinea pigs (n=48) were fed for 7 days with low [25 mg/kg bodyweight (bw)/day] and high (525 mg/kg bw/day) doses of ascorbic acid. Then half of the animals were exposed to noise (90 dB for 1 h). The hearing levels were recorded beforehand, on the 3rd and 7th days after feeding, and directly after noise exposure. Finally, the organ of Corti and the lateral wall were removed from the inner ear and incubated separately for 6 h in culture medium, and the nitrite content was determined in the supernatant. RESULTS: Compared with low-dose feeding, feeding of high doses of ascorbic acid resulted in a reduction of hearing impairment of about 8 dB after noise exposure. A correlation between hearing improvement and decreased NO production was detectable for both cochlea regions but was more pronounced in the lateral wall. CONCLUSION: A high dose of ascorbic acid lowers NO production in the inner ear, reduces hearing loss, and protects the cochlea from nitroactive stress.


Sujet(s)
Acide ascorbique/administration et posologie , Cochlée/effets des médicaments et des substances chimiques , Cochlée/physiopathologie , Perte d'audition/étiologie , Perte d'audition/prévention et contrôle , Monoxyde d'azote/métabolisme , Bruit/effets indésirables , Animaux , Cochons d'Inde , Perte d'audition/métabolisme , Mâle , Transduction du signal/effets des médicaments et des substances chimiques
8.
HNO ; 56(10): 996-1002, 2008 Oct.
Article de Allemand | MEDLINE | ID: mdl-18810373

RÉSUMÉ

In the clinical routine, the diagnostic of the lateral gait is often comparable with a complete peripheral vestibular function examination. Diseases of the otolithic organs, with the saccule and utricle are not identified with conventional clinical examination methods. In more than 50% of patients with thermal hypostimulation, orientation tests show a simultaneous pathology of the utricle function. Participation of the saccule has been described for vestibular neuropathy, Menière's disease, bilateral vestibulopathy and acoustic neurinoma. Both otolithic organs are included in posttraumatic vertigo, a recognition, which will influence expert opinions in the future. Only by an exact diagnostic of diseases of the otolithic organs can individual disease courses be differential diagnostically separated from each other.


Sujet(s)
Troubles neurologiques de la marche/diagnostic , Troubles neurologiques de la marche/thérapie , Membrane des statoconies , Maladies vestibulaires/diagnostic , Maladies vestibulaires/thérapie , Humains
9.
Laryngorhinootologie ; 87(12): 870-3, 2008 Dec.
Article de Allemand | MEDLINE | ID: mdl-18609463

RÉSUMÉ

BACKGROUND: Nowadays, tonsillotomy is an accepted operating procedure for the diagnosis of tonsillar hyperplasia in small children. Up to now many different techniques such as laser, radiofrequency, coblation or micro-debrider have been used. In this study, for the first time bipolar coagulation scissors were utilized. METHODS: Up to December 2006, a total of 91 children with benign tonsillar hyperplasia were tonsillotomized by bipolar coagulation scissors. Of these 91 children, 38 (average age 74 months) were recruited for this study. Pre-operative and post-operative complaints were documented and the success of the operation was evaluated by the parents. RESULTS: In more than 90 % of the children, pre-operative complaints had disappeared completely after surgery. The operation was considered by all parents to have been very helpful. With no child did re-tonsillotomy or tonsillectomy have to be performed in the observation interval, which was a maximum of three years. CONCLUSION: Tonsillotomy with the bipolar coagulation scissors is a reliable method of surgery in children with tonsillar hypertrophy. This type of scissors offers an ideal combination of dissection and coagulation. From an economic point of view, the bipolar coagulation scissors offer a clear advantage over laser.


Sujet(s)
Électrocoagulation/instrumentation , Tonsille palatine/anatomopathologie , Tonsille palatine/chirurgie , Tonsilles pharyngiennes/anatomopathologie , Tonsilles pharyngiennes/chirurgie , Enfant , Enfant d'âge préscolaire , Association thérapeutique , Troubles de la déglutition/étiologie , Troubles de la déglutition/chirurgie , Femelle , Études de suivi , Humains , Hyperplasie , Mâle , Complications postopératoires/étiologie , Récidive , Ronflement/étiologie , Ronflement/chirurgie
10.
Acta Otolaryngol ; 126(6): 587-93, 2006 Jun.
Article de Anglais | MEDLINE | ID: mdl-16720442

RÉSUMÉ

CONCLUSIONS: Subjective visual vertical (SVV) estimation during on-axis rotation provides an efficient screening test of utricle function. The survey demonstrates that isolated disorders of peripheral utricular function can occur while SCC function appears normal. OBJECTIVE: The present study aimed to investigate estimation of SVV during constant velocity yaw rotation (with the head held on-axis--to enhance any asymmetry between right and left utricular responses), as a useful screening test. MATERIALS AND METHODS: In all, 230 patients were recruited from the dizziness clinic. For each patient, the SVV was estimated (a) while held stationary, and (b) during constant angular velocity (240 degrees/s), with the head centred on-axis. Bithermal caloric testing was also performed in 201 of the patients. RESULTS: Of those patients with normal SVV results during stationary testing, 18.3% were pathological during rotation testing. In those cases with pathological SVV during stationary testing, a significantly greater deviation from the norm was observed during rotation (p<0.001). Of those patients with normal caloric responses, 44.4% showed pathological SVV estimates; this increased to 54.3% for cases with unilateral weakness, and 56.5% for unilateral loss. No clear correlation was found between reports of tilt illusion and pathological SVV, respectively, between rotatory vertigo and pathological caloric responses.


Sujet(s)
Kinesthésie/physiologie , Orientation/physiologie , Membrane des statoconies/physiopathologie , Saccule et utricule/physiopathologie , Maladies vestibulaires/diagnostic , Épreuves vestibulaires , Adulte , Sujet âgé , Épreuves vestibulaires caloriques , Électro-oculographie , Femelle , Humains , Illusions/physiologie , Mâle , Dépistage de masse , Adulte d'âge moyen , Valeurs de référence , Réflexe vestibulo-oculaire/physiologie , Reproductibilité des résultats , Vertige/physiopathologie , Maladies vestibulaires/physiopathologie
12.
Histol Histopathol ; 20(2): 339-50, 2005 04.
Article de Anglais | MEDLINE | ID: mdl-15736036

RÉSUMÉ

Potassium ions are a prerequisite for the development and regulation of sensory cell stimulation in the inner ear. From the potassium-rich endolymph the ions flow into the sensory cells apically and are released basolaterally. After transport pathways of various lengths potassium is released again into the endolymph - in the cochlea by marginal cells of the stria vascularis, in the vestibular labyrinth by dark cells. While this long recycling pathway is relatively well-known in the cochlea, few studies have been conducted on the semicircular canal ampullae (SCCA) where its morphological basis is largely unknown. According to the present electron microscopic findings, potassium ions are initially released into the extracellular space during stimulation of the sensory cells and then absorbed by supporting and light cells. Finally they are transported transcellularly over numerous very long gap junctions into the region of the dark cells. From here they move to an extracellular compartment, which is more or less completely sealed off basally by basal plates of the light cells. Apically the intercellular space between light and dark cells is sealed by junctional complexes. This newly identified space in the SCCA corresponds to the extracellular compartment between the marginal and intermediate cells in the stria vascularis. At both sites, the cochlea and the SCCA, this probably serves as a regulatory valve, reservoir or storage space, particularly for potassium ions. It is likely that the different morphology of the ion transport pathways is related to the different flow levels of potassium ions expressed by the different levels of the so-called endocochlear potential and concomitant movement of other ions in the cochlea and SCCA.


Sujet(s)
Columbidae/anatomie et histologie , Columbidae/métabolisme , Potassium/métabolisme , Canaux semicirculaires osseux/métabolisme , Canaux semicirculaires osseux/ultrastructure , Animaux , Cochlée/métabolisme , Cochlée/ultrastructure , Espace extracellulaire/métabolisme , Transport des ions , Microscopie électronique
13.
HNO ; 51(12): 993-7, 2003 Dec.
Article de Allemand | MEDLINE | ID: mdl-14647929

RÉSUMÉ

BACKGROUND AND OBJECTIVE: Basaloid squamous cell carcinoma s a rare, highly malignant carcinoma variant typically situated in the tongue base, supraglottis and pyriform sinus. It is usually only diagnosed at a very advanced stage due to its tendency towards submucosal growth, deep infiltration and early local and distant metastases. PATIENTS/METHODS: The case described involves a 39-year-old man with the clinical and histopathological findings typical for this neoplasm. RESULTS: In contrast to simple squamous cell carcinomas, the basaloid variant with its very poor prognosis calls for therapeutic decisions that give particular consideration to quality of life. It should be stressed that highly invasive surgery is justified only in exceptional cases because of the high local recurrence rate and early distant metastases. CONCLUSIONS: The case presented shows that radio- and chemotherapeutic approaches are just as important as surgery.


Sujet(s)
Carcinome basosquameux/thérapie , Tumeurs du larynx/thérapie , Tumeurs de l'oropharynx/thérapie , Adulte , Marqueurs biologiques tumoraux/analyse , Carcinome basosquameux/diagnostic , Carcinome basosquameux/anatomopathologie , Carcinome basosquameux/secondaire , Transformation cellulaire néoplasique/anatomopathologie , Traitement médicamenteux adjuvant , Association thérapeutique , Diagnostic différentiel , Humains , Cartilages laryngés/anatomopathologie , Tumeurs du larynx/diagnostic , Tumeurs du larynx/anatomopathologie , Laryngoscopie , Larynx/anatomopathologie , Thérapie laser , Tumeurs du poumon/diagnostic , Tumeurs du poumon/anatomopathologie , Tumeurs du poumon/secondaire , Noeuds lymphatiques/anatomopathologie , Mâle , Évidement ganglionnaire cervical , Invasion tumorale/anatomopathologie , Tumeurs de l'oropharynx/diagnostic , Tumeurs de l'oropharynx/anatomopathologie , Partie orale du pharynx/anatomopathologie , Radiothérapie adjuvante
15.
J Vestib Res ; 13(4-6): 215-25, 2003.
Article de Anglais | MEDLINE | ID: mdl-15096665

RÉSUMÉ

Attention is directed towards the recently developed unilateral tests of saccular and utricular function. Together with the now widely used head-thrust test and the standard caloric test for semicircular canal function, these provide for a more comprehensive unilateral examination of labyrinth function. The efficacy of vestibular evoked myogenic potentials (VEMP) as a direct unilateral test of saccular function is currently being demonstrated in an increasing number of reports. Furthermore, the relevant neuronal pathways have been delineated in animal studies, so that all evidence points to the validity of the VEMP as a saccule-mediated response. Concerning utricular function, considerable headway has been made using the unilateral centrifugation paradigm. Testing is performed with a variable radius rotary chair with constant velocity rotation about the earth-vertical axis. Displacing the head by 3.5-4 cm from the rotation axis, the eccentrically positioned utricle is stimulated unilaterally by the resultant centrifugal force. This paradigm can be employed to elicit a utriculo-ocular response (UOR) or to permit measurement of the subjective visual vertical (SVV). More recently, it has also been demonstrated that testing during normal, on-centre yaw axis rotation is often sufficient to localise peripheral otolith dysfunction by means of SVV estimation. This test mode can be easily integrated into routine clinical testing. To illustrate the efficacy of such differential testing, the findings from two patients are presented that demonstrate for the first time an isolated unilateral utricular dysfunction.


Sujet(s)
Saccule et utricule/physiologie , Animaux , Centrifugation , Électrophysiologie , Humains , Membrane des statoconies/physiologie , Maladies vestibulaires/physiopathologie , Épreuves vestibulaires
17.
HNO ; 50(5): 470-8, 2002 May.
Article de Allemand | MEDLINE | ID: mdl-12089813

RÉSUMÉ

Tonsillotomy, the partial resection of hyperplastic tonsils, is generally rejected in Germany as a treatment option for obstructions of the isthmus faucium in early childhood. We think this approach merits consideration. The favorable results obtained with tonsillotomy in the University Hospital Benjamin Franklin (n = 637), a private clinic, and an ENT practice with surgical facilities (n = 189) showed that there is no justification for adhering to literature reports of severe late complications with scarred tonsillar crypts and peritonsillar abscesses. No patient has developed any of these complications thus far. Following tonsillotomy, preoperative complaints (snoring, respiratory obstruction, dysphagia, and failure to grow) decreased considerably. Thus, tonsillotomy proved to be a suitable modality for treating tonsillar hyperplasia in early childhood. The prerequisite for long-term success is strict limitation of this intervention to the diagnosis of tonsillar hyperplasia.


Sujet(s)
Obstruction des voies aériennes/chirurgie , Thérapie laser , Tonsille palatine/anatomopathologie , Amygdalectomie , Amygdalite/chirurgie , Obstruction des voies aériennes/anatomopathologie , Enfant , Enfant d'âge préscolaire , Femelle , Études de suivi , Humains , Hyperplasie/anatomopathologie , Hyperplasie/chirurgie , Mâle , Études rétrospectives , Amygdalite/anatomopathologie
18.
Alcohol Clin Exp Res ; 26(6): 836-40, 2002 Jun.
Article de Anglais | MEDLINE | ID: mdl-12068252

RÉSUMÉ

BACKGROUND: Alcoholics are at risk of developing major complications in the postoperative period. Adequate prophylactic treatment, as well as preoperative abstinence, can significantly decrease the rate of complications. However, the preoperative diagnosis of alcoholism is difficult to establish. The purpose of this study was to assess whether three preoperative visits, an alcohol-related questionnaire (CAGE), and the laboratory markers carbohydrate-deficient transferrin (CDT) and gamma-glutamyltransferase (GGT) would increase the rate of detection of chronic alcoholics. METHODS: The study included the Departments of ENT, Facial and Maxillofacial Surgery, and General Surgery of a university hospital; 705 male patients were assessed for tumor surgery of the upper digestive tract and were allocated to 5 different groups. All patients were seen three times, and five different strategies were used to detect chronic alcoholics. The gold standard was the diagnosis of alcohol misuse made by an experienced (blinded) investigator according to the DSM-III-R. The main outcome measurements were the detection rates of the different test strategies. RESULTS: By clinical routine alone, only 16% were detected during the first visit and 34% after three visits. If the CAGE questionnaire was added, sensitivity increased to 64%. The further addition of GGT or CDT led to 80 and 85% detections, respectively. A combination of all tests had a sensitivity of 91%. CONCLUSIONS: To detect more alcoholic patients at risk for major complications, patients should be seen more often, and additional diagnostic tools such as the CAGE, CDT, and GGT should be used before surgery.


Sujet(s)
Alcoolisme/diagnostic , Alcoolisme/chirurgie , Tumeurs de l'appareil digestif/chirurgie , Soins préopératoires/méthodes , Adulte , Sujet âgé , Alcoolisme/sang , Loi du khi-deux , Tumeurs de l'appareil digestif/sang , Humains , Mâle , Adulte d'âge moyen , /méthodes , /statistiques et données numériques , Soins préopératoires/statistiques et données numériques , Enquêtes et questionnaires
19.
Histol Histopathol ; 16(4): 1161-74, 2001 10.
Article de Anglais | MEDLINE | ID: mdl-11642736

RÉSUMÉ

Earlier morphological studies of the epithelial structure in the semicircular canals of mammals have focused on the sensory cells of the crista ampullaris. This report draws attention to the fact that there exist at least seven further cell types in the horizontal ampulla walls of pigeon with various functions; the role of ion- and H2O-transporting epithelial cells is dealt with here in detail. While the dark cells appear to play a decisive role in the regulation of ionic composition, the cells in the planum semilunatum may transport H2O and assist in the regulation of endolymph volume. In addition, protein-secreting structures are located in the apical region of the cells of the planum semilunatum. The question whether the proteins are dispersed in the endolymph or contribute to cupula formation remains unclear. The morphology and possible functions of these two cell types are discussed on the basis of electron microscopic results.


Sujet(s)
Columbidae/métabolisme , Oreille interne/métabolisme , Cellules épithéliales/métabolisme , Cellules épithéliales/ultrastructure , Eau/métabolisme , Animaux , Transport biologique actif , Membrane cellulaire/ultrastructure , Fixateurs , Tanins hydrolysables , Transport des ions , Microscopie électronique , Terminaisons nerveuses/métabolisme , Terminaisons nerveuses/ultrastructure , Neurones afférents/métabolisme , Neurones afférents/ultrastructure , Inclusion en plastique , Fixation tissulaire
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