일과성 소음성 난청의 회복에 따른 와우신경말단의 변화

서진경; 임현우; 박홍주; 박장호; 정종우

추천

검색

자료유형: 학술저널

저자정보: 서진경 임현우 박홍주 박장호 정종우

저널정보: 대한이비인후과학회 대한이비인후-두경부외과학회지 대한이비인후과학회지 두경부외과학 제56권 제4호

발행연도: 2013.1

수록면: 206 - 211 (6page)

이용수

📌

연구주제

📖

연구배경

🔬

연구방법

🏆

연구결과

초록· 키워드

오류제보하기

Background and Objectives Overexposure to intense sound can cause temporary or permanent hearing loss. Post-exposure recovery of thresholds has been assumed to indicate reversal of damage to the inner ear without persistent consequences for auditory function. However, there was a report that acoustic overexposures causing moderate temporary threshold shift caused acute loss of afferent nerve terminals and delayed degeneration of the cochlear ganglion cells while cochlear sensory cells were intact. The purpose of the study was to evaluate the numerical changes of ribbon synapses and efferents to the outer hair cells in ears with temporary noise-induced threshold shifts. Materials and Methods Four-week old CBA mice with normal Preyer’s reflexes were used. Mice were exposed to white noise of 110 dB SPL for one hour. Auditory brainstem response (ABR) and distortion-product otoacoustic emission (DPOAE) were recorded before exposure and at four different post-exposure times, 1, 3, 5, and 7 days after noise exposure. Ribbon synapses and efferents near cochlear nerve terminals were stained and calculated in the control group mice at two post-exposure times, 3 and 5 days after the exposure. Results In the noise-exposed ears, there was no loss of hair cells, in either inner hair cells or outer hair cells. ABR and DPOAE showed maximum threshold shifts after noise-exposure; they returned to the normal pre-exposure values by at day 5. The number of ribbon synapses tended to decrease at 3 days after noise-exposure, but the number of efferent fibers was not statistically different from those of the control mice. Conclusion Our results suggest that the loss of ribbon synapses could be related with the recovery course of temporary threshold shift, even to the point of full hearing recovery.

#Auditory hair cells #Noise-induced hearing loss #Presynaptic terminals #Synapses #Temporary threshold shifts.

참고문헌 (15)

참고문헌 신청

Glowatzki E / 2002 / Transmitter release at the hair cell ribbon synapse / Nat Neurosci 5 (2) : 147 ~ 154

Kujawa SG / 2006 / Acceleration of age-related hearing loss by early noise exposure: evidence of a misspent youth / J Neurosci 26 (7) : 2115 ~ 2123

Kujawa SG / 2009 / Adding insult to injury: cochlear nerve degeneration after “temporary” noise-induced hearing loss / J Neurosci 29 (45) : 14077 ~ 14085

Liberman MC / 1982 / Acute and chronic effects of acoustic trauma: cochlear pathology and auditory nerve pathophysiology, In New perspectives on noise-induced hearing loss / Raven : 105

Liberman MC / 1984 / Single-neuron labeling and chronic cochlear pathology. III. Stereocilia damage and alterations of threshold tuning curves / Hear Res 16 (1) : 55 ~ 74