TY - JOUR
T1 - Density of motility-related charge in the outer hair cell of the guinea pig is inversely related to best frequency
AU - Santos-Sacchi, Joseph
AU - Kakehata, Seiji
AU - Kikuchi, Toshihiko
AU - Katori, Yukio
AU - Takasaka, Tomonori
N1 - Funding Information:
This work was supported by the National Institutes of Health, National Institute for Deafness and other Communication Disorders (DC00273). We thank Margaret Mazzucco for technical help. We also thank Dr. Akira Tonosaki and Dr. Hiroshi Washioka for EM equipment use and technical support.
PY - 1998/11/13
Y1 - 1998/11/13
N2 - Whole cell voltage clamp and freeze fracture were used to study the electrophysiological and ultrastructural correlates of the outer hair cell (OHC) lateral membrane molecular motors. We find that specific voltage- dependent capacitance, which derives from motility-related charge movement, increases as cell length decreases. This increasing non-linear charge density predicts a corresponding increase in sensor-motor density. However, while OHC lateral membrane particle density increases, a quantitative correspondence is absent. Thus, the presumed equivalence of particle and motor is questionable. The data more importantly indicate that whereas the voltage driving OHC motility, i.e. the receptor potential, may decrease with frequency due to the OHC's low-pass membrane filter, the electrical energy (Q x V) supplied to the lateral membrane will tend to remain stable. This conservation of energy delivery is likely crucial for the function of the cochlear amplifier at high frequencies.
AB - Whole cell voltage clamp and freeze fracture were used to study the electrophysiological and ultrastructural correlates of the outer hair cell (OHC) lateral membrane molecular motors. We find that specific voltage- dependent capacitance, which derives from motility-related charge movement, increases as cell length decreases. This increasing non-linear charge density predicts a corresponding increase in sensor-motor density. However, while OHC lateral membrane particle density increases, a quantitative correspondence is absent. Thus, the presumed equivalence of particle and motor is questionable. The data more importantly indicate that whereas the voltage driving OHC motility, i.e. the receptor potential, may decrease with frequency due to the OHC's low-pass membrane filter, the electrical energy (Q x V) supplied to the lateral membrane will tend to remain stable. This conservation of energy delivery is likely crucial for the function of the cochlear amplifier at high frequencies.
KW - Capacitance
KW - Cochlea
KW - Gating charge
KW - Membranes
KW - Motility
KW - Outer hair cell
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U2 - 10.1016/S0304-3940(98)00788-5
DO - 10.1016/S0304-3940(98)00788-5
M3 - Article
C2 - 9855363
AN - SCOPUS:0032515072
VL - 256
SP - 155
EP - 158
JO - Neuroscience Letters
JF - Neuroscience Letters
SN - 0304-3940
IS - 3
ER -