Intense noise exposure activates JNK signal via generation of nitric oxide in cochlear spiral ligament fibrocytes

Constitutively expressed endothelial nitric oxide synthase (eNOS) is supposed to play a role in noise-induced nitric oxide (NO)-production. It is commonly known that intense noise exposure results in inducible NOS (iNOS) expression and increased NO-production, but knowledge about a contribution of the eNOS isoform is still lacking. Effects of noise exposure on eNOS immunolabeling were determined in male guinea pigs ( n=24). For light microscopic analysis, 11 animals were exposed to 90 dB for 1 hr and 6 animals were used as controls. After exposure, eNOS immunostaining was performed on paraffin sections, and the staining intensities were quantified for 4 cochlear regions. For electron microscopic analysis, 2 animals were exposed for 2 hr to 90 dB and 5 animals were used as controls. The intensity of eNOS immunolabeling was found to be already comprehensively increased 1 hr after noise exposure to 90 dB. At the ultrastructural level, a clear increase in eNOS immunolabeling was found in microtubules-rich areas of cochlear cuticular structures. Hence, our findings indicate that the reticular lamina forming the endolymph–perilymph barrier at the apical side of the organ of Corti is involved in a fast intrinsic otoprotective mechanism of the cochlea.

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A voltage- and Ca2+-dependent big conductance K channel in cochlear spiral ligament fibrocytes

Pflügers Archiv - European Journal of Physiology ◽

10.1007/s00424-002-0976-9 ◽

2003 ◽

Vol 445 (6) ◽

pp. 683-692 ◽

Cited By ~ 13

Author(s):

F. Liang ◽

A. Niedzielski ◽

B. A. Schulte ◽

S. S. Spicer ◽

D. J. Hazen-Martin ◽

...

Keyword(s):

K Channel ◽

Spiral Ligament ◽

Spiral Ligament Fibrocytes

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Prestin gene expression in the rat cochlea following intense noise exposure

Hearing Research ◽

10.1016/j.heares.2006.08.011 ◽

2006 ◽

Vol 222 (1-2) ◽

pp. 54-61 ◽

Cited By ~ 35

Author(s):

Guang-Di Chen

Keyword(s):

Gene Expression ◽

Noise Exposure ◽

Rat Cochlea ◽

Intense Noise

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Spiral ligament fibrocytes release chemokines in response to otitis media pathogens

Acta Oto-Laryngologica ◽

10.1080/00016480500452525 ◽

2006 ◽

Vol 126 (6) ◽

pp. 564-569 ◽

Cited By ~ 39

Author(s):

Sung-Kyun Moon ◽

Raekil Park ◽

Sung-Kyun Moon ◽

Raekil Park ◽

...

Keyword(s):

Otitis Media ◽

Spiral Ligament ◽

Spiral Ligament Fibrocytes

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Changes in endocochlear potential during anoxia after intense noise exposure

Hearing Research ◽

10.1016/0378-5955(90)90076-2 ◽

1990 ◽

Vol 44 (2-3) ◽

pp. 143-149 ◽

Cited By ~ 12

Author(s):

Jian Wang ◽

Wei-jia Dong ◽

Ji-sheng Chen

Keyword(s):

Noise Exposure ◽

Endocochlear Potential ◽

Intense Noise

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Intermittent Exposure to Noise: Effects on Hearing

Annals of Otology Rhinology & Laryngology ◽

10.1177/000348948309200618 ◽

1983 ◽

Vol 92 (6) ◽

pp. 623-628 ◽

Cited By ~ 9

Author(s):

Joseph Sataloff ◽

Robert T. Sataloff ◽

Raymond A. Yerg ◽

Hyman Menduke ◽

Robert P. Gore

Keyword(s):

Hearing Loss ◽

Noise Exposure ◽

Continuous Exposure ◽

Hearing Results ◽

Noise Effects ◽

High Frequencies ◽

Severe Loss ◽

Intermittent Exposure ◽

Intense Noise ◽

Continuous Noise

Most studies of the effects of noise upon hearing have dealt with continuous noise exposure. Previous reports on intermittent exposure to noise concluded that it causes less damage to hearing than does continuous exposure to noise of the same intensity. In this investigation, 12,000 workers were screened to find 295 subjects who met the strict criteria of the study. Most of the subjects were exposed to jackhammer noise at peak levels of 118 dBA. Intermittent exposure to intense noise results in very severe loss in high frequencies but relatively little or no hearing loss in the lower frequencies even after many years of exposure. This differs substantially from the effects of continuous exposure to noise of the same intensity. It remains to be determined whether this pattern of hearing results from intermittent exposure to all sorts of noise or only from the kinds of sources investigated in this study.

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