Acute Effects of Irradiation on Middle Ear Mucosa

Single field, fixed irradiation of bilateral tympanic cavities using 200-kV x-rays was administered to five guinea pigs. The irradiation dose was 30 Gy. They were killed immediately after irradiation, and bilateral middle ear mucosa was examined for ciliary activity and epithelial structure. Significant deterioration of the ciliary activity in the middle ear mucosa was observed, proximal as well as distal to the eustachian tube. Electron microscopy showed various changes in the irradiated middle ear mucosa. The most conspicuous findings were hyperreactivity in secretion, vacuolation of ciliated cells, and stomal edema.

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Effects of Platelet Activating Factor on the Tubotympanic Mucosa and Inner Ear in the Guinea Pig

Annals of Otology Rhinology & Laryngology ◽

10.1177/000348949810701012 ◽

1998 ◽

Vol 107 (10) ◽

pp. 876-884 ◽

Cited By ~ 4

Author(s):

Yoshiharu Ohno ◽

Yoshihiro Ohashi ◽

Hideki Okamoto ◽

Yoshikazu Sugiura ◽

Yoshiaki Nakai

Keyword(s):

Hearing Loss ◽

Sensorineural Hearing Loss ◽

Inner Ear ◽

Otitis Media ◽

Middle Ear ◽

Otitis Media With Effusion ◽

Platelet Activating Factor ◽

Sensorineural Hearing ◽

Ciliary Activity ◽

Middle Ear Mucosa

The effect of platelet activating factor (PAF) was studied to elucidate its role in the pathogenesis of otitis media and sensorineural hearing loss. The PAF alone did not induce a reduction of ciliary activity of the cultured middle ear mucosa. However, a dose-dependent decrease in ciliary activity was observed in the presence of the medium containing both PAF and macrophages. Intravenous injection of PAF did not induce dysfunction of the mucociliary system or morphologic changes of epithelium in the tubotympanum, but cytoplasmic vacuolization and ballooning were observed in the inner ear within 1 hour after injection of PAF. In contrast, intratympanic injection of PAF induced mucociliary dysfunction and some pathologic changes in the tubotympanum. Intratympanic inoculation of PAF induced no pathologic findings in the inner ear. These results suggest that PAF is at least partially involved in the pathogenesis of certain middle ear diseases such as otitis media with effusion. Additionally, PAF might be involved in the pathogenesis of some types of unexplained sensorineural hearing loss.

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Regenerated Middle Ear Mucosa after Tympanoplasty. Part I. Transmission Electron Microscopy

Otolaryngology ◽

10.1177/019459988609400314 ◽

1986 ◽

Vol 94 (3) ◽

pp. 339-343 ◽

Cited By ~ 4

Author(s):

Roberto Gamoletti ◽

Paola Poggi ◽

Mario Sanna ◽

Carlo Zini

Keyword(s):

Electron Microscopy ◽

Middle Ear ◽

Goblet Cells ◽

Secretory Cells ◽

Canal Wall ◽

Ciliated Cells ◽

Middle Ear Mucosa ◽

Morphologic Characteristics ◽

Transmission Electron ◽

Ultrastructural Appearance

The ultrastructural appearance of the regenerated middle ear mucosa—found at the second operation of staged intact canal wall tympanoplasty (ICWT) with mastoidectomy—has been evaluated with the transmission electron microscope. The regenerated epithelium showed all the morphologic characteristics of the normal middle ear mucosa: ciliated cells, noncillated cells, and secretory cells. All of these (Including goblet cells) have been found in the specimens. It is concluded that a normal middle ear mucosa regenerates to cover all denuded bone surfaces after the first operation of staged ICWT with mastoidectomy, when silicone rubber sheeting has been used to prevent adhesions and maintain an air-containing middle ear space.

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Acute Effects of Sulfur Dioxide Exposure on the Middle Ear Mucosa

Annals of Otology Rhinology & Laryngology ◽

10.1177/000348948909800413 ◽

1989 ◽

Vol 98 (4) ◽

pp. 301-307 ◽

Cited By ~ 17

Author(s):

Yoshihiro Ohashi ◽

Yoshiaki Nakai ◽

Hiroyuki Koshimo ◽

Hiroshi Ikeoka ◽

Yusuke Esaki

Keyword(s):

Sulfur Dioxide ◽

Middle Ear ◽

Atmospheric Pollutants ◽

Ciliary Activity ◽

Middle Ear Effusion ◽

Middle Ear Mucosa ◽

Proximal Site ◽

Mucociliary Function ◽

Distal Site ◽

Ear Effusion

A variety of atmospheric pollutants are known to depress mucociliary function in the respiratory system. Since the mucociliary function in the middle ear is similar, and the middle ear may be invaded by atmospheric pollutants, we decided to investigate the possible contribution of sulfur dioxide to middle ear effusion. Guinea pigs were exposed for 24 hours to 300 ppm of sulfur dioxide or air. Immediately after exposure, ciliary activity and epithelial structure were examined close to the tympanic orifice (proximal site) and more distal to it (distal site). In the animals exposed to sulfur dioxide, no effusion was found in the tympanic cavity. Ciliary activity was reduced only in the distal site. Electron microscopy demonstrated hypersecretion in the proximal site and severe pathologic changes in the distal site. Although the normally functioning cilia in the proximal site may prevent retention of surplus secretions in the ear, sulfur dioxide may promote middle ear effusion when combined with other detrimental factors, because it stimulates mucus secretion in the proximal site and impairs ciliary function in the distal site.

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Tissue Culture of Human Adult Adenoids and of Middle Ear Mucosa

Annals of Otology Rhinology & Laryngology ◽

10.1177/000348947608500303 ◽

1976 ◽

Vol 85 (3) ◽

pp. 327-333 ◽

Cited By ~ 8

Author(s):

Ilana Drucker ◽

Ziva Weisman ◽

Jacob Sadé

Keyword(s):

Middle Ear ◽

Ciliary Activity ◽

Organ Cultures ◽

Middle Ear Mucosa ◽

Monolayer Growth ◽

Stratified Squamous Epithelium ◽

Inducing Factors ◽

Developmental Characteristics ◽

Mucociliary Epithelia

The increased number of mucus producing cells as well as the presence of stratified squamous epithelium in pathological and experimental middle ear conditions, point towards the possibility of metaplastic changes of the middle ear mucosa, similar to the metaplastic capabilities of respiratory mucosae in general, as observed clinically or provoked experimentally. The purpose of this study was to develop a model of postembryonic human respiratory mucosae, in vitro, for the study of triggering or inducing factors involved in its normal and metaplastic differentiation. Explants from adenoids and middle ear mucosa were cultured, both as organ cultures and monolayers, for periods of up to two weeks, and their developmental characteristics were studied and described. Over 50% of the explants showed mitosis, epithelial and monolayer growth, ciliary activity and differentiation into ciliated and into mucus-producing cells. Adenoid explants were grown in air without and with added 5% CO2. Under the latter conditions, the proportion of explants and monolayers showing ciliary activity was 50% greater. It is concluded that this model might be suitable for further studies of the factors which control cyto-differentiation in mucociliary epithelia. Maintaining its growth for a longer period would, however, be desirable.

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Acute effects of isopropyl alcohol exposure on the middle ear mucosa

Journal of Applied Toxicology ◽

10.1002/jat.2550070310 ◽

1987 ◽

Vol 7 (3) ◽

pp. 205-211 ◽

Cited By ~ 18

Author(s):

Yoshihiro Ohashi ◽

Yoshiaki Nakai ◽

Hiroshi Ikeoka ◽

Hiroyuki Koshimo ◽

Yusuke Esaki ◽

...

Keyword(s):

Middle Ear ◽

Isopropyl Alcohol ◽

Alcohol Exposure ◽

Acute Effects ◽

Middle Ear Mucosa

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Ultrastructure of the Middle Ear Mucosa

Annals of Otology Rhinology & Laryngology ◽

10.1177/00034894760850s208 ◽

1976 ◽

Vol 85 (2_suppl) ◽

pp. 30-35 ◽

Cited By ~ 8

Author(s):

Erwin Hentzer

Keyword(s):

Middle Ear ◽

Secretory Granules ◽

Goblet Cells ◽

Respiratory Epithelium ◽

Secretory Cells ◽

Secretory Product ◽

Ciliated Cells ◽

Loose Connective Tissue ◽

Middle Ear Mucosa ◽

Subepithelial Layer

Histologic studies of recent years have definitely concluded that the epithelium of the middle ear is a modified respiratory epithelium with ciliated and secretory cells, including goblet cells. These cells, like the ciliated cells, are developd from the basal cell and are just ordinary secretory cells completely filled with secretory granules. For different reasons it is postulated, that the dark secretory granules are prestages of the actual secretory product presenting as light granules and that dark and light granules do not represent different secretory capacities of the cell. The subepithelial layer which consists of loose connective tissue is a structure of just as great importance as the epithelial layer.

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Regenerated Middle Ear Mucosa after Tympanoplasty. Part II. Scanning Electron Microscopy

Otolaryngology ◽

10.1177/019459988609400404 ◽

1986 ◽

Vol 94 (4) ◽

pp. 430-434 ◽

Cited By ~ 4

Author(s):

Roberto Gamoletti ◽

Paolo Lanzarini ◽

Mario Sanna ◽

Carlo Zini

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Electron Microscope ◽

Scanning Electron Microscope ◽

Middle Ear ◽

Ciliated Cells ◽

Secretory Material ◽

Middle Ear Mucosa ◽

Ultrastructural Appearance ◽

Scanning Electron

The ultrastructural appearance of the regenerated middle ear epithelium, found at the second operation of staged ICWT with mastoidectomy, has been investigated herein with the scanning electron microscope. The regenerated epithelium consists of flat nonciliated cells, “elevated” nonciliated cells with microvilli, and ciliated cells. Secretory material is present on the surface of the “elevated” nonciliated cells surrounding the ciliated ones. Regeneration of the mucosa occurs following precise topographic differences that mimic the distribution of epithelial cells in the normal middle ear. It is confirmed that a morphologically normal middle ear epithelium regenerates to cover all denuded bone surfaces within 12 months—after first stage ICWT with mastoidectomy—when silicone rubber sheeting has been used to maintain an aerated middle ear and mastoid space.

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Fine Structures of the Normal Mucosa in Developing Rat Middle Ear

Annals of Otology Rhinology & Laryngology ◽

10.1177/00034894760855s201 ◽

1976 ◽

Vol 85 (5_suppl2) ◽

pp. 1-19 ◽

Cited By ~ 14

Author(s):

Shoichi Maeda ◽

Goro Mogi ◽

Motow Oh

Keyword(s):

Middle Ear ◽

Secretory Granules ◽

Transitional Zone ◽

Normal Mucosa ◽

Secretory Cells ◽

Ciliated Cells ◽

Middle Ear Mucosa ◽

Fine Structures ◽

Developing Rat ◽

Fetal Stage

Forty-two fetal and 90 developing young rats were studied electron microscopically to obtain a normal cellular distribution pattern of middle ear mucosa. The results showed that while ciliated columnar or cuboidal cells interspersed with secretory cells were predominantly distributed around the tympanic orifice and transitional zone, cuboidal or squamous nonciliated cells without secretory granules were numerous in the remaining part of the bulla. Development of ciliated cells started at the 17th or 18th fetal day, paralleling that of secretory cells. The number of ciliated and secretory cells increased rapidly after birth. Glands were not found in the osseous tube, tympanic orifice, or other portions of the middle ear cavity in fetal, newborn, or suckling rats, while they are abundant in the cartilaginous portion of the tube. The findings of this study indicate that both secretory and ciliated cells are normal components of middle ear mucosa although these cells are restricted to the tympanic orifice and transitional zone, and that the mucociliary defense system starts to develop during the fetal stage.

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