Ionic basis of membrane potential in outer hair cells of guinea pig cochlea

@article{Ashmore1986IonicBO,
  title={Ionic basis of membrane potential in outer hair cells of guinea pig cochlea},
  author={Jonathan F Ashmore and Robert W. Meech},
  journal={Nature},
  year={1986},
  volume={322},
  pages={368-371}
}
Mammalian hearing involves features not found in other species, for example,the separation of sound frequencies depends on an active control of the cochlear mechanics1,2.The force-generating component in the cochlea is likely to be the outer hair cell(OHC), one of the two types of sensory cell through which current is gated by mechano-electrical transducer channels sited on the apical surface3.Outer hair cells isolated in vitro have been shown to be motile4,5 and capable of generating forces at… 
A calcium-activated nonselective cationic channel in the basolateral membrane of outer hair cells of the guinea-pig cochlea
TLDR
The patch-clamp technique was used to investigate ion channels in the basolateral perilymph-facing membrane of freshly isolated outer hair cells (OHCs) from the guinea-pig cochlea, finding a Ca2+-activated nonselective cationic channel that might participate in the control of membrane potential and modulate the motility of OHCs.
BK Channels Mediate Cholinergic Inhibition of High Frequency Cochlear Hair Cells
TLDR
The findings suggest that basal (high frequency) outer hair cells may employ an alternative mechanism of efferent inhibition mediated by BK channels instead of SK2 channels, which may be related to the unique acetylcholine receptors that have evolved in mammalian hair cells compared to those of other vertebrates.
Two types of voltage-dependent potassium channels in outer hair cells from the guinea pig cochlea.
TLDR
The most frequent K+ channel had a low conductance and a small outward rectification in symmetrical K+ conditions and was found significantly more frequently in cell-attached and inside-out patches when the pipette contained 100 μM acetylcholine.
Lead ( Pb 2 + ) modulation of potassium currents of guinea pig outer hair cells
TLDR
The effects of Pb 2 + on the potassium currents of O HC are not remarkable and therefore OHC are probably not a major cause of purported peripheral hearing loss observed in Pb + -exposed animals and humans.
A biophysical model of an inner hair cell.
TLDR
A biophysical model of an IHC is presented that indicates activation of slow voltage-gated potassium channels may lead to receptor potentials whose dc component decreases during the stimulus, and membrane potential hyperpolarizes when the stimulus is turned off.
Regulation of ionic currents by protein kinase A and intracellular calcium in outer hair cells isolated from the guinea-pig cochlea
TLDR
The results show that OHC potassium channels are regulated by background phosphorylation through protein kinase A and dephosphorylation by protein phosphatase, but with different sensitivities.
Receptor Potential of Outer Hair Cells Isolated from Base to Apex of the Adult Guinea-Pig Cochlea: Implications for Cochlear Tuning Mechanisms
TLDR
The amplitude and phase of the receptor potential of OHCs in response to direct mechanical stimu­ lation of the stereocilia bundle were measured for cells isolated from along the entire length of the adult guinea-pig cochlea.
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The identification of three voltage- and ion-dependent conductances which may contribute to the electrical tuning mechanism of the turtle cochlea frequency tuning are reported: a non-inactivating calcium Conductance, an A-type K+ conductance, and a Ca2+ -activated K+ Conductance.
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TLDR
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TLDR
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TLDR
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