Quinine-induced alterations of electrically evoked otoacoustic emissions and cochlear potentials in guinea pigs

Jiefu Zheng, Tianying Ren, Anand Parthasarathi, Alfred Nuttall

Research output: Contribution to journalArticle

20 Citations (Scopus)

Abstract

Quinine is a well-known ototoxic drug which may affect portions of the auditory system with different biochemical effects, causing reversible hearing loss and tinnitus. Recent investigations indicate that quinine at high concentrations can act directly on cochlear outer hair cells to affect their motility and the mechanical response of the basilar membrane. This study aimed to investigate the effect of quinine on the electromotility of outer hair cells in vivo by means of measuring the electrically evoked otoacoustic emissions (EEOAEs), and the relationship between EEOAE and hearing sensitivity alterations in guinea pigs. Quinine was infused into the scala tympani with concentrations between 0.05 and 5 mM. An alternating current (35 μA RMS) swept from 400 Hz to 40 kHz was applied to the round window to evoke the EEOAE. The compound action potential (CAP), cochlear microphonic (CM) and summating potential (SP) were also measured. Results show that quinine affects the EEOAE in a dose-dependent manner and that its effects are reversible. Two aspects of the EEOAE were affected by quinine, depending on concentration: (1) the 'fine structure' only for concentrations below 0.1 mM and (2) the overall amplitude and the 'fine structure' for concentrations above 0.1 mM. At 5 mM the fine structure was completely absent and the mean amplitude of the EEOAE greatly decreased. Multiple component analysis shows the short delay component of the EEOAE is related to the mean value of the amplitude spectrum while the long delay component is related to the fine structure. The alterations of the EEOAE are roughly comparable to that of the cochlear potentials. A 'threshold concentration' for quinine's effects was found at 25 μM. CAP was significantly affected at 25 μM while EEOAE, CM and SP were not. Enhancement of the EEOAE amplitude was noticed in five out of 20 animals in the current study. The enhancement appears only related to the EEOAE mean level or short delay component. The results suggest that quinine can affect in vivo electromotility of outer hair cells at low concentration and therefore change the cochlear amplifier performance via an effect on electro-mechanical transduction. Its effects on the cochlear spiral ganglion neurons and/or their presynaptic process are also suggested, and these are speculated to be the primary sites for quinine's effects on the auditory system.

Original languageEnglish (US)
Pages (from-to)124-134
Number of pages11
JournalHearing Research
Volume154
Issue number1-2
DOIs
StatePublished - 2001

Fingerprint

Quinine
Cochlea
Guinea Pigs
Outer Auditory Hair Cells
Cochlear Microphonic Potentials
Action Potentials
Scala Tympani
Basilar Membrane
Spiral Ganglion
Tinnitus
Hearing Loss
Hearing
Neurons

Keywords

  • Cochlear potential
  • Electromotility
  • Guinea pig
  • Otoacoustic emission
  • Ototoxicity
  • Outer hair cell
  • Quinine

ASJC Scopus subject areas

  • Sensory Systems

Cite this

Quinine-induced alterations of electrically evoked otoacoustic emissions and cochlear potentials in guinea pigs. / Zheng, Jiefu; Ren, Tianying; Parthasarathi, Anand; Nuttall, Alfred.

In: Hearing Research, Vol. 154, No. 1-2, 2001, p. 124-134.

Research output: Contribution to journalArticle

@article{d43ce85c9b2e4bfaac0d1a03bde1abba,
title = "Quinine-induced alterations of electrically evoked otoacoustic emissions and cochlear potentials in guinea pigs",
abstract = "Quinine is a well-known ototoxic drug which may affect portions of the auditory system with different biochemical effects, causing reversible hearing loss and tinnitus. Recent investigations indicate that quinine at high concentrations can act directly on cochlear outer hair cells to affect their motility and the mechanical response of the basilar membrane. This study aimed to investigate the effect of quinine on the electromotility of outer hair cells in vivo by means of measuring the electrically evoked otoacoustic emissions (EEOAEs), and the relationship between EEOAE and hearing sensitivity alterations in guinea pigs. Quinine was infused into the scala tympani with concentrations between 0.05 and 5 mM. An alternating current (35 μA RMS) swept from 400 Hz to 40 kHz was applied to the round window to evoke the EEOAE. The compound action potential (CAP), cochlear microphonic (CM) and summating potential (SP) were also measured. Results show that quinine affects the EEOAE in a dose-dependent manner and that its effects are reversible. Two aspects of the EEOAE were affected by quinine, depending on concentration: (1) the 'fine structure' only for concentrations below 0.1 mM and (2) the overall amplitude and the 'fine structure' for concentrations above 0.1 mM. At 5 mM the fine structure was completely absent and the mean amplitude of the EEOAE greatly decreased. Multiple component analysis shows the short delay component of the EEOAE is related to the mean value of the amplitude spectrum while the long delay component is related to the fine structure. The alterations of the EEOAE are roughly comparable to that of the cochlear potentials. A 'threshold concentration' for quinine's effects was found at 25 μM. CAP was significantly affected at 25 μM while EEOAE, CM and SP were not. Enhancement of the EEOAE amplitude was noticed in five out of 20 animals in the current study. The enhancement appears only related to the EEOAE mean level or short delay component. The results suggest that quinine can affect in vivo electromotility of outer hair cells at low concentration and therefore change the cochlear amplifier performance via an effect on electro-mechanical transduction. Its effects on the cochlear spiral ganglion neurons and/or their presynaptic process are also suggested, and these are speculated to be the primary sites for quinine's effects on the auditory system.",
keywords = "Cochlear potential, Electromotility, Guinea pig, Otoacoustic emission, Ototoxicity, Outer hair cell, Quinine",
author = "Jiefu Zheng and Tianying Ren and Anand Parthasarathi and Alfred Nuttall",
year = "2001",
doi = "10.1016/S0378-5955(01)00229-5",
language = "English (US)",
volume = "154",
pages = "124--134",
journal = "Hearing Research",
issn = "0378-5955",
publisher = "Elsevier",
number = "1-2",

}

TY - JOUR

T1 - Quinine-induced alterations of electrically evoked otoacoustic emissions and cochlear potentials in guinea pigs

AU - Zheng, Jiefu

AU - Ren, Tianying

AU - Parthasarathi, Anand

AU - Nuttall, Alfred

PY - 2001

Y1 - 2001

N2 - Quinine is a well-known ototoxic drug which may affect portions of the auditory system with different biochemical effects, causing reversible hearing loss and tinnitus. Recent investigations indicate that quinine at high concentrations can act directly on cochlear outer hair cells to affect their motility and the mechanical response of the basilar membrane. This study aimed to investigate the effect of quinine on the electromotility of outer hair cells in vivo by means of measuring the electrically evoked otoacoustic emissions (EEOAEs), and the relationship between EEOAE and hearing sensitivity alterations in guinea pigs. Quinine was infused into the scala tympani with concentrations between 0.05 and 5 mM. An alternating current (35 μA RMS) swept from 400 Hz to 40 kHz was applied to the round window to evoke the EEOAE. The compound action potential (CAP), cochlear microphonic (CM) and summating potential (SP) were also measured. Results show that quinine affects the EEOAE in a dose-dependent manner and that its effects are reversible. Two aspects of the EEOAE were affected by quinine, depending on concentration: (1) the 'fine structure' only for concentrations below 0.1 mM and (2) the overall amplitude and the 'fine structure' for concentrations above 0.1 mM. At 5 mM the fine structure was completely absent and the mean amplitude of the EEOAE greatly decreased. Multiple component analysis shows the short delay component of the EEOAE is related to the mean value of the amplitude spectrum while the long delay component is related to the fine structure. The alterations of the EEOAE are roughly comparable to that of the cochlear potentials. A 'threshold concentration' for quinine's effects was found at 25 μM. CAP was significantly affected at 25 μM while EEOAE, CM and SP were not. Enhancement of the EEOAE amplitude was noticed in five out of 20 animals in the current study. The enhancement appears only related to the EEOAE mean level or short delay component. The results suggest that quinine can affect in vivo electromotility of outer hair cells at low concentration and therefore change the cochlear amplifier performance via an effect on electro-mechanical transduction. Its effects on the cochlear spiral ganglion neurons and/or their presynaptic process are also suggested, and these are speculated to be the primary sites for quinine's effects on the auditory system.

AB - Quinine is a well-known ototoxic drug which may affect portions of the auditory system with different biochemical effects, causing reversible hearing loss and tinnitus. Recent investigations indicate that quinine at high concentrations can act directly on cochlear outer hair cells to affect their motility and the mechanical response of the basilar membrane. This study aimed to investigate the effect of quinine on the electromotility of outer hair cells in vivo by means of measuring the electrically evoked otoacoustic emissions (EEOAEs), and the relationship between EEOAE and hearing sensitivity alterations in guinea pigs. Quinine was infused into the scala tympani with concentrations between 0.05 and 5 mM. An alternating current (35 μA RMS) swept from 400 Hz to 40 kHz was applied to the round window to evoke the EEOAE. The compound action potential (CAP), cochlear microphonic (CM) and summating potential (SP) were also measured. Results show that quinine affects the EEOAE in a dose-dependent manner and that its effects are reversible. Two aspects of the EEOAE were affected by quinine, depending on concentration: (1) the 'fine structure' only for concentrations below 0.1 mM and (2) the overall amplitude and the 'fine structure' for concentrations above 0.1 mM. At 5 mM the fine structure was completely absent and the mean amplitude of the EEOAE greatly decreased. Multiple component analysis shows the short delay component of the EEOAE is related to the mean value of the amplitude spectrum while the long delay component is related to the fine structure. The alterations of the EEOAE are roughly comparable to that of the cochlear potentials. A 'threshold concentration' for quinine's effects was found at 25 μM. CAP was significantly affected at 25 μM while EEOAE, CM and SP were not. Enhancement of the EEOAE amplitude was noticed in five out of 20 animals in the current study. The enhancement appears only related to the EEOAE mean level or short delay component. The results suggest that quinine can affect in vivo electromotility of outer hair cells at low concentration and therefore change the cochlear amplifier performance via an effect on electro-mechanical transduction. Its effects on the cochlear spiral ganglion neurons and/or their presynaptic process are also suggested, and these are speculated to be the primary sites for quinine's effects on the auditory system.

KW - Cochlear potential

KW - Electromotility

KW - Guinea pig

KW - Otoacoustic emission

KW - Ototoxicity

KW - Outer hair cell

KW - Quinine

UR - http://www.scopus.com/inward/record.url?scp=0034980164&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0034980164&partnerID=8YFLogxK

U2 - 10.1016/S0378-5955(01)00229-5

DO - 10.1016/S0378-5955(01)00229-5

M3 - Article

C2 - 11423223

AN - SCOPUS:0034980164

VL - 154

SP - 124

EP - 134

JO - Hearing Research

JF - Hearing Research

SN - 0378-5955

IS - 1-2

ER -