Calcium Ions and the Adaptation of the Transducer Current in Turtle Cochlear Hair Cells
If a maintained displacement is imposed upon the ciliary bundle of a hair cell, many of the transducer channels that initially open in response to the stimulus eventually close. This process of adaptation of the transducer current has been investigated in several preparations, by delivering test steps to the bundle following a conditioning step to induce adaptation. The results of such experiments have shown that even after the transducer current has declined extensively from its initial peak value, the transducer channels can still be re-opened by further displacement of the cell’s ciliary bundle towards the kinocilium (Corey & Hudspeth. 1983a,b; Eatock, Corey & Hudspeth, 1987; Assad, Hacohen & Corey, 1989; Crawford, Evans & Fettiplace, 1989). There is therefore no evidence that transducer channels enter a true inactivated state.
KeywordsHair Cell Hair Bundle Basilar Papilla Extracellular Calcium Concentration Transducer Current
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