Direct effects of intraperilymphatic reactive oxygen species generation on cochlear function

doi:10.1016/S0378-5955(96)00126-8

Hearing Research

Volume 101, Issues 1–2, 1 November 1996, Pages 14-22

https://doi.org/10.1016/S0378-5955(96)00126-8 Get rights and content

Abstract

Reactive oxygen species (ROS) generation may play a role in ototoxicity, however, the specific effects of ROS generation upon cochlear function are unstudied. Therefore, guinea pig cochleas were instilled with artificial perilymph (AP), H₂O₂, or confirmed generating systems for the superoxide anion (O₂⁻) or the hydroxyl radical (OH^.), or with an ROS system plus its respective scavenger — catalase (CAT), superoxide dismutase (SOD) or deferoxamine (DEF). O₂⁻ generating system instillation led to significantly greater mean high frequency compound action potential (CAP) threshold shifts at 10 and 120 min post infusion than seen in AP control or SOD/O₂⁻ groups. H₂O₂ group CAP threshold shifts were significantly greater than control and CAT/H₂O₂ group values at 10(16–30 kHz), and 120 min (above 12 kHz). OH^. generating system instillation led to significantly greater CAP threshold shifts at 10(12–30 kHz) and 120 min (above 6 kHz) than seen in control or DEF/OH^. groups. No significant CAP differences were found between controls and scavenger/ROS groups. Mean 1.0 μV cochlear microphonic isopotential curve shift values did not systematically differ among groups. The rapid degradation of high frequency CAP threshold sensitivity seen here may provide insight into the portion of cochlear dysfunction which is ROS-mediated following noise, radiation or chemical exposures.

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Research paperDirect effects of intraperilymphatic reactive oxygen species generation on cochlear function

Abstract

Biochem. Biophys. Res. Commun.

Toxicol. Appl. Pharmacol.

Toxicol. Appl. Pharmacol.

Toxicol. Appl. Pharmacol.

Hear. Res.

Hear. Res.

Hear. Res.

Hear. Res.

Anal. Biochem.

Free Rad. Biol. Med.

J. Biol. Chem.

Hear. Res.

Hear. Res.

Fund. Appl. Toxicol.

Outer hair cell electromotility and otoacoustic emissions

Ear Hear.

Direct effects of intraperilymphatic reactive oxygen generation on cochlear potentials

Ass. Res. Otolaryngol.

A model for transducer action in the cochlea

Quart. Rev. Biol.

Research paper
Direct effects of intraperilymphatic reactive oxygen species generation on cochlear function