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

@article{Kujawa1996TimevaryingAI,
  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},
  year={1996},
  volume={97},
  pages={153-164}
}
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
TLDR
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
  • R. Bobbin
  • Chemistry, Medicine
  • Hearing Research
  • 2002
TLDR
Overall, low intensity evoked responses were more sensitive and were suppressed to a greater extent by both drugs, consistent with the hypothesis that release of Ca(2+) from ryanodine receptor Ca( 2+) stores, possibly in outer hair cells and supporting cells, affects the function of the cochlear amplifier. Expand
Pharmacological evidence that endogenous ATP modulates cochlear mechanics
TLDR
Results show that extracellular application of 5-10 microM ATP to OHCs and Deiters' cells induced an inward current that was reduced by both suramin and cibacron, which may be evidence that endogenous ATP alters active cochlear mechanics. Expand
Thapsigargin suppresses cochlear potentials and DPOAEs and is toxic to hair cells
TLDR
In chronic animals, thapsigargin destroyed many outer hair cells and some inner hair cells, especially in the basal turns, consistent with the hypothesis that the inhibition of the SERCAs affects the function of the cochlear amplifier and outerhair cells to a greater degree than it affects other functions of thecochlea. Expand
Additional pharmacological evidence that endogenous ATP modulates cochlear mechanics
TLDR
Results show that PPADS reduced the inward current evoked by 5-10 microM ATP in OHCs, Deiters' cells, Hensen's cells and pillar cells, which may be evidence that endogenous ATP acting on cells in the organ of Corti alters cochlear mechanics. Expand
Bi-phasic intensity-dependent opioid-mediated neural amplitude changes in the chinchilla cochlea: partial blockade by an N-Methyl-D-Aspartate (NMDA)-receptor antagonist.
TLDR
The data suggests that endogenous dynorphins within lateral efferent olivocochlear neurons differentially modulate auditory neural excitation, possibly through cochlear NMDA receptors and glutamate. Expand
Influence of contralateral acoustic stimulation on the quadratic distortion product f2–f1 in humans
TLDR
The observed sensitivity of f2-f1 to contralateral noise stimulation could hence be resulting from a shift of the operating state and/or a change in the gain of the cochlear amplification due tocontralateral induced efferent modulation of the outer hair cell properties. Expand
Possible roles of nitric oxide in the physiology and pathophysiology of the guinea pig cochlea
TLDR
The results suggest that NO has a major effect on the physiology of the inner and outer hair cells. Expand
Cochlear compression: effects of low-frequency biasing on quadratic distortion product otoacoustic emission.
  • L. Bian
  • Materials Science, Medicine
  • The Journal of the Acoustical Society of America
  • 2004
TLDR
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
TLDR
An immunocytochemical map of the efferent terminals that contain acetylcholine (ACh), CGRP, and GABA was produced in the mouse to understand the roles and origins of γ‐aminobutyric acid (GABA) and calcitonin gene‐related peptide (CGRP), and there are prominent GABAergic, cholinergic, and CGRPergic innervations in the OHC and IHC regions. Expand
...
1
2
...

References

SHOWING 1-10 OF 47 REFERENCES
Time-varying alterations in the f2−f1 DPOAE response to continuous primary stimulation I: Response characterization and contribution of the olivocochlear efferents
TLDR
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
TLDR
Ca2+ and L-type Ca2+ channels are involved in the function of the hair cells and the generation of the negative SP, and Mg2+ appears to be a selective antagonist of the Ca2- channel involved in transmitter release. Expand
Slow variation of the amplitude of acoustic distortion at f 2−f 1 in awake rabbits
TLDR
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.
TLDR
Rapid adaptation of the monaurally evoked 2f1-f2 DPOAE is probably mediated by reflex activity in ipsilaterally responsive OC neurons innervating outer hair cells, and the effects of this ipsilateral reflex on D POAE amplitudes are typically twice as large as those of the contralateral reflex. Expand
Nimodipine, an L-channel Ca2+ antagonist, reverses the negative summating potential recorded from the guinea pig cochlea
TLDR
The hypothesis that L-type Ca2+ channels are directly involved in the operation of the organ of Corti is supported by the results of the test, which support the hypothesis that the channels are integrally involved in generation of a negative summating potential and the dc motion of the cochlear partition described by others. Expand
Modulation of ƒ2 −ƒ1 : Evidence for a GABA-ergic efferent system in apical cochlea of the guinea pig
TLDR
The results are evidence for a role for a GABA-ergic efferent system in the modulation of outer hair cell mechanics in the apical cochlea. Expand
Contralateral sound suppresses distortion product otoacoustic emissions through cholinergic mechanisms
TLDR
Results confirm the findings of Puel and Rebillard (1990) that contralateral WBN can suppress DPOAEs in anesthetized guinea pigs and suggest that this efferent control of the cochlear mechanical response can either be mediated by both nicotinic and muscarinic cholinergic receptors, or that a single receptor with as yet undescribed structure and pharmacology mediates effects seen. Expand
Efferent neural control of cochlear mechanics? Olivocochlear bundle stimulation affects cochlear biomechanical nonlinearity
TLDR
The results demonstrate that the COCB effect is postsynaptic, probably mediated by outer hair cells, and suggest that the normal cochlea contains an active biomechanical mechanism which reduces the damping of the cochlear-partition motion and is modulated by activating the efferents. Expand
The Ca2+ activity of cochlear endolymph of the guinea pig and the effect of inhibitors
TLDR
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
...
1
2
3
4
5
...