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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 -
Annals of Anatomy = Anatomischer... May 2020Nipples represent a highly specialized skin with capital importance in mammals for breastfeeding and additionally in humans due to sexuality. The histological studies...
Nipples represent a highly specialized skin with capital importance in mammals for breastfeeding and additionally in humans due to sexuality. The histological studies regarding this region are scarce, so 42 human nipples were studied to describe the morphology of the nipple innervation. Our results exclude the presence of a rich innervation on nipple's skin or superficial dermis, thus definitely excluding nipple skin from the concept glabrous skin. The presence of mechanoreceptors is limited to scarce Merkel cells on the epidermis and some corpuscular capsulated and non-capsulated structures in the dermis; Merkel cells progressively decrease with ageing. No Meissner corpuscles were found and the rare Pacinian corpuscles identified were close to vascular structures and embroidered in the mammary fatty tissue. The great sensitivity observed functionally on the breast and especially in the nipple can be morphologically explained by two elements; on the one hand there is a rich smooth muscle innervation present in the deep dermis; on the other hand the mammary gland demonstrate Piezo2 expression in many glandular cells, with two differentiated patterns in the ductal and in the acinar tissue of the breast. The role of Piezo2 in the normal mammary gland is discussed.
Topics: Adolescent; Adult; Aged; Aged, 80 and over; Calcium-Binding Proteins; Child; Female; Humans; Immunohistochemistry; Ion Channels; Merkel Cells; Middle Aged; Neoplasm Proteins; Nipples; Pacinian Corpuscles; Sebaceous Glands; Sensory Receptor Cells; Young Adult
PubMed: 31911160
DOI: 10.1016/j.aanat.2019.151456 -
Journal of Plastic Surgery and Hand... Feb 2021Dupuytren disease (DD) has been associated with enlarged Pacinian corpuscles (PCs) and with PCs having a greater number of lamellae. Based on these associations, we...
PURPOSE
Dupuytren disease (DD) has been associated with enlarged Pacinian corpuscles (PCs) and with PCs having a greater number of lamellae. Based on these associations, we hypothesized that subjects with DD would have altered sensitivity to high-frequency vibrations and that the changes would be more prominent at 250 Hz, where healthy subjects demonstrate the highest sensitivity.
METHODS
A novel device was created to deliver vibrations of specific frequencies and amplitudes to the fingers and palm. Using a Psi-marginal adaptive algorithm, vibrotactile perception thresholds (VPTs) were determined in 36 subjects with DD and 74 subjects without DD. Experiments were performed at 250 Hz and 500 Hz at the fingertip and palm. The VPTs were statistically analyzed with respect to disease status, age, gender, location tested, and frequency tested.
RESULTS
We found that VPT increases with age, which agrees with findings by others. Women showed greater sensitivity (i.e. lower VPT) than men. Men exhibited lower sensitivity in DD versus healthy subjects, but the results were not statistically significant. In subjects with DD presenting unilaterally, the unaffected hand was more sensitive than the affected hand, in particular for a 250 Hz stimulus applied to the finger.
CONCLUSIONS
The data on vibration sensitivity obtained from a large group of subjects with and without DD present interesting trends that may serve as a useful reference to future DD researchers. Understanding additional symptoms of DD may facilitate development of novel diagnostic or prognostic protocols.
Topics: Aged; Case-Control Studies; Dupuytren Contracture; Female; Humans; Male; Middle Aged; Sensory Thresholds; Sex Factors; Touch; Vibration
PubMed: 33043747
DOI: 10.1080/2000656X.2020.1828898 -
Journal of Microscopy and Ultrastructure 2022The cell is the basic structural unit of all living organisms. Most of the cells forming the human body share the basic components, but there are many categories that... (Review)
Review
The cell is the basic structural unit of all living organisms. Most of the cells forming the human body share the basic components, but there are many categories that have specific light and electron microscopic characteristics. This review shed a light on these cell categories and their morphologies. Stem cell category is the cells responsible for the regeneration of damaged or lost cells, whereas protein-secreting cells are those responsible for the production and secretion of proteins. Protein-secreting cells have specific characters such as basophilic cytoplasm and vesicular nucleus by light microscope; these are confirmed by an electron microscope that shows rough endoplasmic reticulum, Golgi apparatus, secretory granules, and mitochondria. Steroid secreting, ion transporting, and contracting categories have specific morphology. Phagocytic cells such as macrophages and neutrophils are characterized by the presence of many lysosomes and phagosomes. Supporting cells are very important category as they not only support but also usually have another function such as myelin formation in Schwann, blood-brain barrier in astrocytes, or modification of response as in Pacinian corpuscle. Many cells showed interrelated characters between different categories, for example, phagocytic cells are able to contract to perform their function in fighting microorganism. Although we have trillions of cells, yet they only fall in some categories. Each cell category has specific morphological characters confirmed by ultrastructural characters. They all adapted to perform the desired functions.
PubMed: 35832316
DOI: 10.4103/jmau.jmau_74_20 -
Biomedical Research (Tokyo, Japan) 2022Peripheral nerves are provided with a blood-nerve barrier which prevents the invasion of harmful substances and pathogens, and also regulates metabolic and ionic... (Review)
Review
Peripheral nerves are provided with a blood-nerve barrier which prevents the invasion of harmful substances and pathogens, and also regulates metabolic and ionic homeostasis within nerve fascicles. The barrier functions are attributed to both the concentric layer of flattened cells in the perineurium and blood vessels running in the endoneurium. The perineurial cells develop continuous tight junctions as a diffusion barrier. In order to take up a predominant nutrient, glucose, the perineurium as well as endoneurial capillaries expresses GLUT1, a glucose transporter. An axon-Schwann cell complex within peripheral nerves utilizes glucose as a major energy source via the GLUT1, as does the brain. Under conditions of a reduced utilization of glucose, only the perineurial cells can transfer other nutrients, namely monocarboxylates such as ketone bodies and lactate via MCT1. Thus, MCT1 colocalizes with GLUT1 in the perineurium but not in endoneurial capillaries. To identify the cellular origins of the nerve sheath, marker proteins such as glial specific S100 protein, GLUT1, endoneurial CD34, and EMA (epithelial membrane antigen) are useful. Immunohistochemical findings for these markers are reviewed in this paper, focusing on the perineurium and endoneurium and their derivatives, Pacinian and Meissner corpuscles. Growing evidence throws light on the critical involvement of the nerve sheaths in the development, maintenance, and diseases of peripheral nerves.
Topics: Glucose; Glucose Transporter Type 1; Ketone Bodies; Lactates; Mucin-1; Peripheral Nerves; S100 Proteins
PubMed: 36244793
DOI: 10.2220/biomedres.43.145 -
Frontiers in Neuroscience 2022Sensory corpuscles, or cutaneous end-organ complexes, are complex structures localized at the periphery of Aβ-axon terminals from primary sensory neurons that primarily...
Sensory corpuscles, or cutaneous end-organ complexes, are complex structures localized at the periphery of Aβ-axon terminals from primary sensory neurons that primarily work as low-threshold mechanoreceptors. Structurally, they consist, in addition to the axons, of non-myelinating Schwann-like cells (terminal glial cells) and endoneurial- and perineurial-related cells. The terminal glial cells are the so-called lamellar cells in Meissner and Pacinian corpuscles. Lamellar cells are variably arranged in sensory corpuscles as a "coin stack" in the Meissner corpuscles or as an "onion bulb" in the Pacinian ones. Nevertheless, the origin and protein profile of the lamellar cells in both morphotypes of sensory corpuscles is quite similar, although it differs in the expression of mechano-gated ion channels as well as in the composition of the extracellular matrix between the cells. The lamellar cells have been regarded as supportive cells playing a passive role in the process of genesis of the action potential, i.e., the mechanotransduction process. However, they express ion channels related to the mechano-electric transduction and show a synapse-like mechanism that suggest neurotransmission at the genesis of the electrical action potential. This review updates the current knowledge about the embryonic origin, development modifications, spatial arrangement, ultrastructural characteristics, and protein profile of the lamellar cells of cutaneous end-organ complexes focusing on Meissner and Pacinian morphotypes.
PubMed: 35356056
DOI: 10.3389/fnins.2022.790130 -
IEEE Transactions on Haptics 2019Recognizing and discriminating vibrotactile stimuli is an essential function of the Pacinian corpuscle. This function has been studied at length in both a computational...
Recognizing and discriminating vibrotactile stimuli is an essential function of the Pacinian corpuscle. This function has been studied at length in both a computational and an experimental setting, but the two approaches have rarely been compared, especially when the computational model has a high level of structural detail. In this paper, we explored whether the predictions of a multiscale, multiphysical computational model of the Pacinian corpuscle can predict the outcome of a corresponding psychophysical experiment. The discrimination test involved either two simple stimuli with frequency in the 160-500 Hz range, or two complex stimuli formed by combining the waveforms for a 100-Hz stimulus with a second stimulus in the 160-500 Hz range. The subjects' ability to distinguish between the simple stimuli increased as the frequency increased, a result consistent with the model predictions for the same stimuli. The model also predicted correctly that subjects would find the complex stimuli more difficult to distinguish than the simple ones and also that the discriminability of the complex stimuli would show no trend with frequency difference.
Topics: Discrimination, Psychological; Humans; Models, Theoretical; Pacinian Corpuscles; Sensory Thresholds; Touch; Touch Perception; Vibration
PubMed: 30932849
DOI: 10.1109/TOH.2019.2903500 -
BioRxiv : the Preprint Server For... Nov 2023Pacinian corpuscle neurons are specialized low-threshold mechanoreceptors (LTMRs) that are tuned to detect high-frequency vibration (~40-2000 Hz), however it is unclear...
Pacinian corpuscle neurons are specialized low-threshold mechanoreceptors (LTMRs) that are tuned to detect high-frequency vibration (~40-2000 Hz), however it is unclear how Pacinians and other LTMRs encode mechanical forces encountered during naturalistic behavior. Here, we developed methods to record LTMRs in awake, freely moving mice. We find that Pacinians, but not other LTMRs, encode subtle vibrations of surfaces encountered by the animal, including low-amplitude vibrations initiated over two meters away. Strikingly, Pacinians are also highly active during a wide variety of natural behaviors, including walking, grooming, digging, and climbing. Pacinians in the hindlimb are sensitive enough to be activated by forelimb- or upper-body-dominant behaviors. Finally, we find that Pacinian LTMRs have diverse tuning and sensitivity. Our findings suggest a Pacinian population code for the representation of vibro-tactile features generated by self-initiated movements and low-amplitude environmental vibrations emanating from distant locations.
PubMed: 37745531
DOI: 10.1101/2023.09.11.557225 -
The Journal of Hand Surgery... Feb 2023We present a patient with Pacinian corpuscle hypertrophy and hyperplasia in the hand and discuss the diagnosis and treatment of this rare condition. A 46-year-old woman...
We present a patient with Pacinian corpuscle hypertrophy and hyperplasia in the hand and discuss the diagnosis and treatment of this rare condition. A 46-year-old woman presented with radiating pain of the left middle finger. A strong Tinel-like sign was elicited between the index and middle fingers. The patient frequently used mobile phone, with the corner of the phone consistently applying pressure on the palm. The surgery was carried out under the microscope and two enlarged cystic lesions under the epineurium were found in the proper digital nerve. Histologic examination revealed hypertrophied Pacinian corpuscle with normal structure. Postoperatively, her symptoms gradually improved. Preoperative diagnosis of this disease is very difficult. Hand surgeons should keep this disease in mind preoperatively. In our case, we would not have been able to identify multiple hypertrophic Pacinian corpuscles without the microscope. An operating microscope is recommended in a surgery of this nature. Level V (Therapeutic).
Topics: Female; Humans; Middle Aged; Fingers; Hand; Hyperplasia; Neuroma; Pacinian Corpuscles; Peripheral Nervous System Diseases; Hypertrophy; Microsurgery; Peripheral Nerves
PubMed: 36803331
DOI: 10.1142/S2424835523720037 -
Skeletal Radiology Oct 2019To provide microdissection and histological confirmation of normal Pacinian corpuscles prospectively identified using MRI in a cadaver model.
OBJECTIVE
To provide microdissection and histological confirmation of normal Pacinian corpuscles prospectively identified using MRI in a cadaver model.
METHODS
3-T MRI of a cadaveric hand specimen was performed with fiduciary markers on the skin. Based on previous descriptions, subcutaneous nodules representing presumed Pacinian corpuscles were localized with respect to the skin markers, and their sizes and depths were recorded. Focused ultrasound was performed to attempt to visualize the corpuscles. Subsequent microdissection was then performed and the presence and location of Pacinian corpuscles were recorded and compared with the findings on MRI. Histological evaluation for each identified corpuscle was performed.
RESULTS
The MRI demonstrated 11 T2-hyperintense palmar subcutaneous nodules around the second through fifth metacarpophalangeal joints. None was visible sonographically. The first eight were dissected and proved to be normal Pacinian corpuscles histologically. In sites devoid of subcutaneous nodules on MRI, subsequent dissection failed to reveal any corpuscles.
CONCLUSION
On MRI, normal Pacinian corpuscles appear as round or oval, T2-hyperintense subcutaneous nodules in the palms, clustered around the metacarpophalangeal joints, and should not be mistaken for pathological conditions.
Topics: Cadaver; Hand; Humans; Magnetic Resonance Imaging; Pacinian Corpuscles; Prospective Studies
PubMed: 31069468
DOI: 10.1007/s00256-019-03223-y