CC BY-NC-ND 4.0 · Laryngorhinootologie 2019; 98(S 02): S328
DOI: 10.1055/s-0039-1686517
Poster
Otology
Georg Thieme Verlag KG Stuttgart · New York

Cochlear expression patterns of endothelial nitric oxide synthase in guinea pigs after loud noise

S Strieth
1  HNO-Klinik der Universitätsmedizin Mainz, Mainz
,
BP Ernst
1  HNO-Klinik der Universitätsmedizin Mainz, Mainz
,
S Becker
1  HNO-Klinik der Universitätsmedizin Mainz, Mainz
,
RH Stauber
1  HNO-Klinik der Universitätsmedizin Mainz, Mainz
,
I Schmidtmann
2  Universitätsmedizin Mainz, Institut für Medizinische Biometrie, Epidemiologie und Informatik, Mainz
,
R Meuser
2  Universitätsmedizin Mainz, Institut für Medizinische Biometrie, Epidemiologie und Informatik, Mainz
,
UR Heinrich
1  HNO-Klinik der Universitätsmedizin Mainz, Mainz
› Author Affiliations
Deutsche Forschungsgemeinschaft (DFG grant STR 1014); Impulsfonds des Landes Rheinland-Pfalz 2017 – 2018 (Research Initiative of the Government of Rhineland-Palatia); BiomaTiCS-Programm der Universitätsmedizin Mainz, ('Biomaterials, Tissues and Cells'-program, University Medical Center Mainz)
Further Information

Publication History

Publication Date:
23 April 2019 (online)

  

Introduction:

Intense noise exposure results in increased nitric oxide (NO)-production by inducible NO-Synthase (iNOS) overexpression. It is unclear, whether the constitutively expressed endothelial nitric oxide synthase (eNOS) may act in an otoprotective manner after noise exposure of the cochlea.

Methods:

Eleven male guinea pigs were exposed to 90 dB SPL for 1 hour (h) and 2 animals for 2h, with 5 or 6 animals serving as controls, respectively. On paraffin sections eNOS immunostaining was analyzed and quantified after noise (1h) in 4 cochlear regions by light microscopy. After 2h noise exposure, an eNOS-specific gold-labeling was quantified on sections of the Organ of Corti at the electron microscopic level.

Results:

The expression of the eNOS isoform in the guinea pig cochlea was found to be already up-regulated 1h after noise exposure in all 4 cochlear regions. At the ultrastructural level, a clear increase of the eNOS expression was located in actin-containing cells linked to the reticular lamina of the Organ of Corti 2h after noise exposure.

Conclusion:

Distinct alterations in of eNOS expression patterns may indicate an early intrinsic otoprotective mechanism of the inner ear after noise exposure.