Time-varying alterations in the f2–f1 DPOAE response to continuous primary stimulation II. Influence of local calcium-dependent mechanisms

  title={Time-varying alterations in the f2–f1 DPOAE response to continuous primary stimulation II. Influence of local calcium-dependent mechanisms},
  author={Sharon G. Kujawa and Maureen Fallon and Ruth A. Skellett and Richard P. Bobbin},
  journal={Hearing Research},
The distortion product otoacoustic emission (DPOAE) corresponding to the frequency f2-f1 displays stereotyped, time-varying amplitude alterations during continuous primary tone stimulation. The origin of these alterations is unknown; however, evidence that efferent neurons contribute little to the changes has been presented (Kujawa et al., 1994a, 1995; Lowe and Robertson, 1995). The present investigation examines the hypothesis that these alterations in f2-f1 amplitude are a reflection of local… Expand
Nitrosoglutathione suppresses cochlear potentials and DPOAEs but not outer hair cell currents or voltage-dependent capacitance 1 A preliminary report was presented at the 18th Midwinter Research Meeting of the Association for Research in Otolaryngology in February 1995. 1
Results show that GSNO suppresses cochlear function, and the actions of GSNO were different from those of other NO donors; therefore, the effects ofGSNO may not be mediated by NO. Expand
Caffeine and ryanodine demonstrate a role for the ryanodine receptor in the organ of Corti
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  • Chemistry, Medicine
  • Hearing Research
  • 2002
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Additional pharmacological evidence that endogenous ATP modulates cochlear mechanics
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Influence of contralateral acoustic stimulation on the quadratic distortion product f2–f1 in humans
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Cochlear compression: effects of low-frequency biasing on quadratic distortion product otoacoustic emission.
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  • Materials Science, Medicine
  • The Journal of the Acoustical Society of America
  • 2004
The results suggest that QDT arises from the compression that coexists with the active hysteresis in cochlear transduction, and modulation of QDT magnitude reflects the dynamic regulation of co chlear transducer gain and compression. Expand
Olivocochlear innervation in the mouse: Immunocytochemical maps, crossed versus uncrossed contributions, and transmitter colocalization
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Time-varying alterations in the f2−f1 DPOAE response to continuous primary stimulation I: Response characterization and contribution of the olivocochlear efferents
The present experiments confirm previous reports of continuous stimulation-related alterations in the amplitude of the quadratic distortion product, f2-f1, and report a novel, suppressive 'off-effect' apparent in f2/f1 amplitude following a short rest from such stimulation, and test the hypothesis that such alterations are mediated by the olivocochlear efferents. Expand
A suppressive ‘‘off‐effect’’ in the f2−f1 DPOAE response to continuous, moderate‐level primary stimulation
Following a short period of amplitude enhancement, the f2−f1 DPOAE can be suppressed during continuous ipsilateral stimulation with primary tones. Evidence for and against efferent control of suchExpand
Magnitude of the negative summating potential varies with perilymph calcium levels
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Slow variation of the amplitude of acoustic distortion at f 2−f 1 in awake rabbits
Qualitatively similar variations in f2-f1 DPOAE amplitude, in the absence of 2f1-f2 amplitude variations, were found in all ears tested, supporting the hypothesis of a dissociation of the generators of the two D POAEs. Expand
The ipsilaterally evoked olivocochlear reflex causes rapid adaptation of the 2f1-f2 distortion product otoacoustic emission.
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Nimodipine, an L-channel Ca2+ antagonist, reverses the negative summating potential recorded from the guinea pig cochlea
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Contralateral sound suppresses distortion product otoacoustic emissions through cholinergic mechanisms
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Efferent neural control of cochlear mechanics? Olivocochlear bundle stimulation affects cochlear biomechanical nonlinearity
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The Ca2+ activity of cochlear endolymph of the guinea pig and the effect of inhibitors
The endolymphatic pH measured with pH-microelectrodes under various conditions indicates that the mechanism of increase in the Ca2+ concentration is attributed not to the liberation ofCa2+ from the surrounding tissues caused by a fall in pH but to the increased influx of Ca2- from perilymph due to the depression of the endocochlear potential. Expand