1987 Fiscal Year Final Research Report Summary
Frequency responsibiligy of the dissociated cochler hair cells of the chick.
| Project/Area Number |
61570079
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| Research Category |
Grant-in-Aid for General Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Research Field |
Neurophysiology and muscle physiology
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| Research Institution | Okazaki National Research Institutes |
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Principal Investigator |
OHMO@RI Harunori Professor,National Institute for Physiological Sciences, 生理学研究所, 教授 (30126015)
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| Project Period (FY) |
1986 – 1987
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| Keywords | Hair cell / cochlear orga / Inner ear / vestibular organ |
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| Research Abstract |
The cochlear hair cell is an auditory recephor cell which transduces vibration of the basilar membrane into an electrical receptor potential,and transmitts the signal to the primary aferent auditody nerve via the synapse. In the cochlear the hair cell is required to nave a transducing capability up to a few 10 kHz of the stimulating frequency. This study was aimed at the analysis of a frequency responsibility of the cochlear hair cell which was voltage clamped after dissociation.
The hair dundle was stimulated via a water coupling by the sinusoidally vibrating glass rod. The mechano-electrical transduction (m-e.t.) currents were recorded under voltage clamp up to the frequency of 3 kHz. These currents demonstrated one to one relationship with the mechanical stimulation of which wavetorm is monitored optically. A systematic phase shift was observed between the mechanical stimulus and the m-e.t. currend. The phase difference increased pu to 1kHz and remained constant at 180 vetween 1 and 3 kHz of stimulus.
The temperature depnedence of the transducing kinetics was studied and the m-e.t.current demonstrated fused waveform at 15゜C rather than deconstrating one to one responses to the stimulation at 1 kHz. This might indicate a limitted freauency responsibility at the lower temperature,and in turn might indicate an existence of a sihnificant potential energy barrier in the gating of this mechanically operated ionic channei.
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