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Neuron Oct 2023Across mammalian skin, structurally complex and diverse mechanosensory end organs respond to mechanical stimuli and enable our perception of dynamic, light touch. How...
Across mammalian skin, structurally complex and diverse mechanosensory end organs respond to mechanical stimuli and enable our perception of dynamic, light touch. How forces act on morphologically dissimilar mechanosensory end organs of the skin to gate the requisite mechanotransduction channel Piezo2 and excite mechanosensory neurons is not understood. Here, we report high-resolution reconstructions of the hair follicle lanceolate complex, Meissner corpuscle, and Pacinian corpuscle and the subcellular distribution of Piezo2 within them. Across all three end organs, Piezo2 is restricted to the sensory axon membrane, including axon protrusions that extend from the axon body. These protrusions, which are numerous and elaborate extensively within the end organs, tether the axon to resident non-neuronal cells via adherens junctions. These findings support a unified model for dynamic touch in which mechanical stimuli stretch hundreds to thousands of axon protrusions across an end organ, opening proximal, axonal Piezo2 channels and exciting the neuron.
Topics: Animals; Merkel Cells; Mechanotransduction, Cellular; Imaging, Three-Dimensional; Ion Channels; Mechanoreceptors; Mammals
PubMed: 37725982
DOI: 10.1016/j.neuron.2023.08.023 -
Purinergic Signalling Mar 2021Purinergic signalling plays important roles in somatosensory and nociceptive transmission in the dorsal horn of the spinal cord under physiological and... (Review)
Review
Purinergic signalling plays important roles in somatosensory and nociceptive transmission in the dorsal horn of the spinal cord under physiological and pathophysiological conditions. Physiologically, ATP mediates excitatory postsynaptic responses in nociceptive transmission in the superficial dorsal horn, and in transmission of innocuous primary afferent inputs in the deep dorsal horn. Additionally, extracellular conversion of ATP to adenosine mediates inhibitory postsynaptic responses from Pacinian corpuscle afferents, and is implicated in analgesia caused by transcutaneous electrical nerve stimulation in humans. In terms of pathological pain, P2X4 receptors de novo expressed on dorsal horn microglia are implicated in pain hypersensitivity following peripheral nerve injury. There is evidence that involvement of such P2X4 receptors is sexually dimorphic, occurring in males but not in females. Thus, the roles of purinergic signalling in physiological and pathological pain processing are complex and remain an ever-expanding field of research.
Topics: Adenosine Triphosphate; Animals; Disease Models, Animal; Humans; Microglia; Neuralgia; Posterior Horn Cells; Receptors, Purinergic; Spinal Cord Dorsal Horn
PubMed: 33169292
DOI: 10.1007/s11302-020-09748-5 -
Micromachines May 2021The Pacinian corpuscle is a highly sensitive mammalian sensor cell that exhibits a unique band-pass sensitivity to vibrations. The cell achieves this band-pass response...
The Pacinian corpuscle is a highly sensitive mammalian sensor cell that exhibits a unique band-pass sensitivity to vibrations. The cell achieves this band-pass response through the use of 20 to 70 elastic layers entrapping layers of viscous fluid. This paper develops and explores a scalable mechanical model of the Pacinian corpuscle and uses the model to predict the response of synthetic corpuscles, which could be the basis for future vibration sensors. The -3dB point of the biological cell is accurately mimicked using the geometries and materials available with off-the-shelf 3D printers. The artificial corpuscles here are constructed using uncured photoresist within structures printed in a commercial stereolithography (SLA) 3D printer, allowing the creation of trapped fluid layers analogous to the biological cell. Multi-layer artificial Pacinian corpuscles are vibration tested over the range of 20-3000 Hz and the response is in good agreement with the model.
PubMed: 34070189
DOI: 10.3390/mi12050574 -
International Journal of Women's... Jun 2021Pacinian corpuscle hyperplasia typically presents as a tender nodule on the volar aspect of the palm or digit, often after trauma. Histologically, it presents as one to... (Review)
Review
OBJECTIVE
Pacinian corpuscle hyperplasia typically presents as a tender nodule on the volar aspect of the palm or digit, often after trauma. Histologically, it presents as one to multiple normal-sized to enlarged Pacinian corpuscles in the deep dermis or subcutaneous adipose tissue. Given its rarity, its pathogenesis is debated and nomenclature is poorly defined. Herein, we present a case of Pacinian corpuscle hyperplasia and review the current literature.
METHODS
A literature review was conducted using PubMed with the following search terms: Pacinian corpuscle hyperplasia, Pacinian corpuscle neuroma, Pacinioma, Pacinian corpuscle hypertrophy, and heterotopic Pacinian corpuscles. All case reports and case series were reviewed for histopathologic evidence of true Pacinian corpuscle hyperplasia. Cadaveric studies, cases without true Pacinian corpuscles, and noncutaneous cases were excluded from our analysis.
RESULTS
Sixty patients with Pacinian corpuscle hyperplasia of the hands and feet (65 cases, some with >1 location) were reviewed. The mean age of presentation was 49.5 years, and women accounted for 60% of cases. Pain was the most commonly reported symptom (55 of 65 cases; 84.6%). Forty-five cases (69.2%) were localized to a digit, most commonly the second digit (17 of 65 cases; 26.2%), and 18 of 65 cases (27.6%) affected the palm, primarily the distal palm. Surgical excision was curative in 50 of 65 cases (76.9%).
CONCLUSION
Although relatively uncommon, Pacinian corpuscle hyperplasia should be considered in the differential diagnosis of a tender nodule on the digit or distal palm, particularly after trauma.
PubMed: 34222593
DOI: 10.1016/j.ijwd.2020.10.005 -
Radiology Case Reports Sep 2023Pacinian corpuscles are mechanoreceptors frequently found between the dermis and subcutaneous tissues of the hands and feet. They are responsible for sensitivity to...
Pacinian corpuscles are mechanoreceptors frequently found between the dermis and subcutaneous tissues of the hands and feet. They are responsible for sensitivity to vibration and pressure. Pacinian corpuscle hyperplasia is a rare cause of induration in the palms of the hands or the soles of the feet, often of unknown origin or occasionally related to neurofibromatosis. It can be characterized by magnetic resonance imaging and is included in the differential diagnosis of anechoic lesions on high-resolution soft tissue ultrasound. The definitive diagnosis is made through histopathologic examination. In this case report, we present the findings of a 29-year-old patient who presented with painful nodules on the palms of both hands, with typical findings on ultrasound and magnetic resonance imaging indicative of Pacinian corpuscle hyperplasia. We also discuss the imaging findings and the differential diagnosis through a non-systematic review. Pacinian corpuscle hyperplasia is a rare condition that can be readily identified by high-resolution ultrasound and magnetic resonance imaging, and it should be considered in the differential diagnosis of hand nodules.
PubMed: 37483376
DOI: 10.1016/j.radcr.2023.06.046 -
BioRxiv : the Preprint Server For... Apr 2024Vibrations are ubiquitous in nature, shaping behavior across the animal kingdom. For mammals, mechanical vibrations acting on the body are detected by mechanoreceptors...
Vibrations are ubiquitous in nature, shaping behavior across the animal kingdom. For mammals, mechanical vibrations acting on the body are detected by mechanoreceptors of the skin and deep tissues and processed by the somatosensory system, while sound waves traveling through air are captured by the cochlea and encoded in the auditory system. Here, we report that mechanical vibrations detected by the body's Pacinian corpuscle neurons, which are unique in their ability to entrain to high frequency (40-1000 Hz) environmental vibrations, are prominently encoded by neurons in the lateral cortex of the inferior colliculus (LCIC) of the midbrain. Remarkably, most LCIC neurons receive convergent Pacinian and auditory input and respond more strongly to coincident tactile-auditory stimulation than to either modality alone. Moreover, the LCIC is required for behavioral responses to high frequency mechanical vibrations. Thus, environmental vibrations captured by Pacinian corpuscles are encoded in the auditory midbrain to mediate behavior.
PubMed: 38496510
DOI: 10.1101/2024.03.08.584077