Age-related changes in cochlear vascular conductance in mice

J. Nadine Brown, Josef M. Miller, Alfred Nuttall

Research output: Contribution to journalArticle

22 Citations (Scopus)

Abstract

Vascular changes contribute to age-related hearing loss but the mechanisms involved in microvascular reactivity, particularly in the aged ear, are still incompletely understood. In this study, possible age-related changes in cochlear blood flow (CBF) and vascular reactivity were studied in presbycusic mice (C57BL/6) and young, age-matched, and old controls (CBA/J) without presbycusis. Reactivity was monitored by laser Doppler flowmetry and assessed by change in cochlear vascular conductance (VC) (defined as the ratio of CBF to blood pressure) in response to round window-applied sodium nitroprusside, a vasodilating agent. Mean VC response of C57BL/6 mice differed from controls both in maximum response and in post-drug recovery time. In C57BL/6 mice, mean VC increased about 28%, in contrast to an increase of over 40% in young and age-matched CBA/J controls. A less elevated VC response, similar to that of the presbycusic mice, was shown by aged (20-21 month) controls. Also, VC response in C57BL/6 mice was sustained throughout the 60 min observation period, while response of most CBA/J controls recovered in 50 min or less. These changes suggest age-dependent, pathologically-related altered responsiveness in cochlear vascular reactivity.

Original languageEnglish (US)
Pages (from-to)189-194
Number of pages6
JournalHearing Research
Volume86
Issue number1-2
DOIs
StatePublished - 1995
Externally publishedYes

Fingerprint

Cochlea
Blood Vessels
Inbred C57BL Mouse
Presbycusis
Laser-Doppler Flowmetry
Nitroprusside
Hearing Loss
Ear
Observation
Blood Pressure
Pharmaceutical Preparations

Keywords

  • Laser Doppler flowmetry
  • Persbycusis
  • Sodium nitroprusside

ASJC Scopus subject areas

  • Sensory Systems

Cite this

Age-related changes in cochlear vascular conductance in mice. / Nadine Brown, J.; Miller, Josef M.; Nuttall, Alfred.

In: Hearing Research, Vol. 86, No. 1-2, 1995, p. 189-194.

Research output: Contribution to journalArticle

Nadine Brown, J. ; Miller, Josef M. ; Nuttall, Alfred. / Age-related changes in cochlear vascular conductance in mice. In: Hearing Research. 1995 ; Vol. 86, No. 1-2. pp. 189-194.
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