Spontaneous Oscillation by Hair Bundles of the Bullfrog's Sacculus

• DOI: 10.1523/jneurosci.23-11-04533.2003
• Publication Date: 2018-04-13T22:30:28Z
• Authors: Pascal Martin; D. Bozovic; Y. Choe; A. J. Hudspeth
• Keywords: Transduction (biophysics)

One prominent manifestation of mechanical activity in hair cells is spontaneous otoacoustic emission, the unprovoked emanation sound by an internal ear. Because active bundle motility probably constitutes process nonmammalian cells, we investigated ability bundles bullfrog's sacculus to produce oscillations that might underlie emissions. When maintained normal ionic milieu ear, many oscillated spontaneously through distances as great 80 nm at frequencies 5–50 Hz. Whole-cell recording disclosed positive phase movement was associated with opening transduction channels. Gentamicin, which blocks channels, reversibly arrested oscillation; drugs affect cAMP phosphorylation pathway and influence myosin altered rate oscillation. Increasing Ca 2+ concentration rendered faster smaller until they were suppressed; lowering moderately chelators had opposite effect. a offset stimulus fiber, transiently suppressed but gradually resumed. Loading partial displacement clamping, simulated presence accessory structures ordinarily attached, increased frequency diminished magnitude These observations accord model arise from interplay bundle's negative stiffness adaptation motors -dependent relaxation gating springs.