title: Mechanical overstimulation of hair bundles: suppression and recovery of active motility.
abstract: We explore the effects of high-amplitude mechanical stimuli on hair bundles of the bullfrog sacculus. Under in vitro conditions, these bundles exhibit spontaneous limit cycle oscillations. Prolonged deflection exerted two effects. First, it induced an offset in the position of the bundle. Recovery to the original position displayed two distinct time scales, suggesting the existence of two adaptive mechanisms. Second, the stimulus suppressed spontaneous oscillations, indicating a change in the hair bundle's dynamic state. After cessation of the stimulus, active bundle motility recovered with time. Both effects were dependent on the duration of the imposed stimulus. External calcium concentration also affected the recovery to the oscillatory state. Our results indicate that both offset in the bundle position and calcium concentration control the dynamic state of the bundle.
authors.affiliation: Department of Physics and Astronomy, University of California Los Angeles, Los Angeles, California, United States of America.
authors.forename: Albert
authors.initials: A
authors.lastname: Kao
authors.forename: Sebastiaan W F
authors.initials: SW
authors.lastname: Meenderink
authors.forename: Dolores
authors.initials: D
authors.lastname: Bozovic
mesh_terms: D000818:Animals; D002118:Calcium / Q000378:metabolism; D002923:Cilia / Q000473:pathology*; D004710:Endolymph / Q000378:metabolism; D006198:Hair Cells, Auditory / Q000502:physiology*; D010812:Physical Stimulation; D011892:Rana catesbeiana; D013997:Time Factors
chemical_list: D002118:Calcium