A5068225495- Hearing, Cochlea, Tinnitus, Genetics
- Marine animal studies overview
- Hearing Loss and Rehabilitation
- Acoustic Wave Phenomena Research
- Ion Channels and Receptors
- Ion channel regulation and function
- Vestibular and auditory disorders
- Neurobiology and Insect Physiology Research
- Connexins and lens biology
- Animal Vocal Communication and Behavior
- Photoreceptor and optogenetics research
- Erythrocyte Function and Pathophysiology
- Neural dynamics and brain function
- Lipid Membrane Structure and Behavior
- Bat Biology and Ecology Studies
- Biochemical Analysis and Sensing Techniques
- Retinal Development and Disorders
- Microfluidic and Bio-sensing Technologies
- Advanced Chemical Sensor Technologies
- Acoustic Wave Resonator Technologies
- Neuroscience and Neuropharmacology Research
- Advanced Thermodynamic Systems and Engines
- Electrolyte and hormonal disorders
- Neuroscience and Neural Engineering
- Neuroscience of respiration and sleep
University of Wisconsin–Madison
2016-2025
University of Cambridge
1982-2006
Keele University
2006
Physiological Society
1938-1991
New York University Press
1989
Bridge University
1971
The mechanical behaviour of the ciliary bundles hair cells in turtle cochlea was examined by deflecting them with flexible glass fibres known compliance during simultaneous intracellular recording cell's membrane potential. Bundle motion monitored through attached fibre partially occluding a light beam incident on photodiode array. change photocurrent assumed to be proportional bundle displacement. For deflexions 1‐100 nm towards kinocilium, stiffness estimated as about 6 X 10(‐4) N/m, top...
1. Intracellular recordings were made from single cochlear hair cells in the isolated half‐head of turtle. The electrical responses recorded under two conditions: (a) when ear was stimulated with low‐intensity tones different frequencies and (b) current steps injected through intracellular electrode. aim experiments to evaluate extent which cochlea's frequency selectivity could be accounted for by properties cells. 2. At low levels acoustic stimulation, amplitude cell's receptor potential...
Outer hair cells (OHCs) provide amplification in the mammalian cochlea using somatic force generation underpinned by voltage-dependent conformational changes of motor protein prestin. However, prestin must be gated membrane potential on a cycle-by-cycle basis and periodic component receptor may greatly attenuated low-pass filtering due to OHC time constant (τ(m)), questioning functional relevance this mechanism. Here, we measured τ(m) from OHCs with range characteristic frequencies (CF)...
Inner ear hair cells detect sound through deflection of stereocilia, the microvilli-like projections that are arranged in rows graded heights. Calcium and integrin-binding protein 2 is essential for hearing localizes to but its exact function unknown. Here, we have characterized two mutant mouse lines, one lacking calcium carrying a human deafness-related Cib2 mutation, show both deaf exhibit no mechanotransduction auditory cells, despite presence tip links gate mechanotransducer channels....
1. Mechano‐electrical transducer currents evoked by deflections of the hair bundle were recorded in turtle isolated cells under whole‐cell voltage clamp. The outcome perfusing with solutions reduced Ca2+ concentration was investigated. 2. current roughly doubled lowering divalent cations from normal (2.2 mM‐Mg2+, 2.8 mM‐Ca2+) to 0 Mg2+, 0.5 mM‐Ca2+. No significant effects on current's kinetics or reversal potential, current‐displacement relationship, noted. 3. If lowered 50 microM (with no...
1. Hair cells were enzymatically isolated from identified regions of the turtle basilar papilla and studied with patch‐electrode technique. The experimental aim was to relate resonance properties seen during current injection membrane currents measured in same cell under whole‐cell voltage clamp. 2. Solitary hair had resting potentials about ‐50 mV, produced a damped oscillation potential at onset termination small step; resonant frequency varied 9 350 Hz between cells, correlated region...
1. Transducer currents were recorded in turtle cochlear hair cells during mechanical stimulation of the bundle. The measured under whole‐cell voltage clamp isolated that firmly stuck to floor recording chamber. 2. Stimuli calibrated by projecting image bundle onto a rapidly scanned 128 photodiode array. This technique showed that, while cell body was immobilized, tip would follow faithfully motion an attached glass probe up frequencies more than 1 kHz. 3. relationship between inward...
1. The electrical responses of single auditory nerve fibres or cochlear hair cells were recorded in the isolated half‐head turtle Pseudemys scripta elegans . Responses to sound stimuli presented tympanum could be for at least 4 hr after isolation. 2. Impulses extracellularly from fibres. For tones suprathreshold intensity impulses occurred with a preferred phase relation (i.e. they phase‐locked) cycles stimulus. Nerve had sharp tuning curves ( Q 10 db = 0·5‐7·5) characteristic frequencies...
Calcium buffers are important for shaping and localizing cytoplasmic Ca2+ transients in neurons. We measured the concentrations of four main calcium-buffering proteins (calbindin-D28k, calretinin, parvalbumin-alpha, parvalbumin-beta) rat cochlear hair cells which signaling is a central element fast transduction synaptic transmission. The were quantified by calibrating immunogold tissue counts against gels containing known amounts each protein, method was verified application to Purkinje...
Sound stimuli are detected in the cochlea by opening of hair cell mechanotransducer (MT) channels, one few ion channels not yet conclusively identified at a molecular level. To define their performance situ, we measured MT channel properties inner cells (IHCs) and outer (OHCs) two locations rat tuned to different characteristic frequencies (CFs). The conductance (in 0.02 mM calcium) from IHCs was estimated as 260 pS both low-frequency mid-frequency positions, whereas that OHCs increased with...
Significance Cochlear hair cells are sensory receptors of the inner ear that detect sound via opening mechanically sensitive transduction channels at tips eponymous hairs. The conductance channel increases two-fold along cochlea, but neither its molecular structure nor mechanism tonotopic variation is known. We show when either two deafness-linked proteins, transmembrane channel-like protein isoform 1 (TMC1) and tetraspan membrane cell stereocilia (TMHS, also known as lipoma HMGIC fusion...
Vibration of the stereociliary bundles activates calcium-permeable mechanotransducer (MT) channels to initiate sound detection in cochlear hair cells. Different regions cochlea respond preferentially different acoustic frequencies, with variation unitary conductance MT contributing this tonotopic organization. Although molecular identity channel remains uncertain, two members transmembrane channel–like family, Tmc1 and Tmc2, are crucial cell mechanotransduction. We measured current amplitude...
Functional mechanoelectrical transduction (MET) channels of cochlear hair cells require the presence transmembrane channel-like protein isoforms TMC1 or TMC2. We show that TMCs are required for normal stereociliary bundle development and distinctively influence channel properties. TMC1-dependent have larger single-channel conductance in outer (OHCs) support a tonotopic apex-to-base gradient. Each MET complex exhibits multiple states ~50 pS increments, basal having more large-conductance...