Related Experiment Video
Updated: Jun 6, 2025
12:07
Physiological Preparation of Hair Cells from the Sacculus of the American Bullfrog Rana catesbeiana
Published on: March 17, 2017
16.8K
Gating-spring stiffness increases outer-hair-cell bundle stiffness, damping, and receptor current
Zenghao Zhu1, Wisam Reid1,2, Dáibhid Ó Maoiléidigh3
1Department of Otolaryngology-Head and Neck Surgery, Stanford University, Stanford, 94304, CA, USA.
Scientific Reports
|December 2, 2024
Summary
Outer-hair-cell bundles (OHBs) use gating springs to amplify sound. Increased stiffness in these springs enhances hearing sensitivity but narrows the dynamic range, revealing a key trade-off in auditory function.
Area of Science:
- Auditory neuroscience
- Mechanobiology
- Biophysics
Background:
- Outer-hair-cell bundles (OHBs) are crucial for hearing, converting sound forces into electrical signals via mechanoelectrical-transduction (MET) channels.
- OHBs possess unique gating springs with higher stiffness than other hair bundles, yet their precise role in OHB mechanics and hearing remains unclear.
Purpose of the Study:
- To investigate how gating-spring stiffness influences the mechanical properties and function of outer-hair-cell bundles.
- To elucidate the contribution of OHB 3D morphology to mechanical regulation and receptor current dynamics.
Main Methods:
- Development and utilization of experimentally-constrained mathematical models of the outer-hair-cell bundle.
- Analysis of the effects of varying gating-spring stiffness on OHB stiffness, damping, receptor current, and dynamic range.
Main Results:
- Increased gating-spring stiffness enhances OHB stiffness and damping.
- The 3D morphology of OHBs modulates the impact of gating-spring stiffness on overall stiffness and damping.
- Gating-spring stiffness increases receptor current but reduces displacement-current dynamic range, while 3D morphology further decreases force-current dynamic range with increasing stiffness.
Conclusions:
- Gating-spring stiffness plays a critical role in regulating the trade-off between hearing threshold and dynamic range.
- OHB 3D morphology significantly influences mechanical responses and dynamic range, interacting with gating-spring stiffness.
- Findings provide insights into the biophysical mechanisms underlying the sensitivity and wide dynamic range of hearing.
More Related Videos
Related Concept Videos
01:22Hair Cells
40.0K
Hair cells are the sensory receptors of the auditory system—they transduce mechanical sound waves into electrical energy that the nervous system can understand. Hair cells are located in the organ of Corti within the cochlea of the inner ear, between the basilar and tectorial membranes. The actual sensory receptors are called inner hair cells. The outer hair cells serve other functions, such as sound amplification in the cochlea, and are not discussed in detail here.
40.0K
01:13The Cochlea
44.5K
The cochlea is a coiled structure in the inner ear that contains hair cells—the sensory receptors of the auditory system. Sound waves are transmitted to the cochlea by small bones attached to the eardrum called the ossicles, which vibrate the oval window that leads to the inner ear. This causes fluid in the chambers of the cochlea to move, vibrating the basilar membrane.
44.5K
01:21G-Protein Gated Ion Channels
4.5K
GPCRs are primarily responsible for our sense of smell, taste, and vision. The binding of a sensory stimulus activates GPCR to stimulate effector proteins, many of which are ion channels in the sensory organs. GPCRs modulate the opening and closing of the target ion channels either directly by binding them, or by releasing second messengers that activate these channels. As ions move across the membrane, the membrane potential is altered, which induces an appropriate response.
Sensory...
Sensory...
4.5K
01:22Muscle Stimulation Frequency
2.0K
The contraction strength of muscles is regulated by motor neurons, which modulate the frequency of action potentials dispatched to the motor units based on the body's requirements. This process of varying the muscle stimulation frequency allows muscles to contract with a force that is precisely tailored to the needs of the moment, whether lifting a feather or a heavy box.
Wave summation
At low firing rates, motor neurons induce individual twitch contractions in muscle fibers. These twitches...
Wave summation
At low firing rates, motor neurons induce individual twitch contractions in muscle fibers. These twitches...
2.0K
01:30Ligand-Gated Ion Channel Receptor: Gating Mechanism
2.1K
Ligand-gated ion channels are transmembrane proteins that play a vital role in intercellular communication and functions of the nervous system. They allow the influx of ions across the membrane once the neurotransmitter binds, allowing the subsequent transmission of electrical excitation across the neurons. Other ligand-gated ion channels, like the γ-aminobutyric acid (GABA) receptor, permit anions like chloride into the cells on the binding of the GABA molecule. Their entry into the cell...
2.1K