scholarly journals Effects of Munari powder on physical and sensory-motor parameters: a preliminary report

2015 ◽  
Vol 25 (2) ◽  
pp. 191
Author(s):  
Nejc Sarabon
Keyword(s):  
Action Potentials ◽  
Pain Threshold ◽  
Mechanical Stimulus ◽  
Nerve Fibers ◽  
Short Report ◽  
Balance Test ◽  
Patch Application ◽  
Sitting Balance ◽  
Sensory Motor ◽  
Trunk Extension

Munari powder is broadly used in physical medicine and rehabilitation to decrease pain and help normalize sensory-motor function. It operates as TPRV1 agonist and “stops” generation of action potentials in pain nerve fibers. This is a short report of a pilot study on 20 subjects. Every subject underwent four visits to our laboratory, where the Munari applications and related measurements of its effects took place. Each of the healthy adults received the following applications: (1) placebo, i.e. 0% cayenne pepper mixture, consisting only of water and kaolin, (2) weak, i.e. 2.5% cayenne pepper mixture, (3) medium, i.e. 5.0% cayenne pepper mixture, and (4) strong, i.e. 10% cayenne pepper mixture. The assessments were carried out before the Munari powder patch application, right after the application, and 15 and 30 min after the termination of the 20-minute Munari powder patch application. We measured subjective cold/hot feeling on visual analogue scale, blood pressure, body temperature, skin light touch sensations, sense for two-point discrimination, and pain threshold to the mechanical stimulus. Besides these tests, maximal voluntary force during isometric trunk extension and the sitting balance test were performed. The preliminary results indicate that the 5% concentration of cayenne pepper mixture is the best choice because no additional effects were observed with the 10% concentration and the effects are higher than with 2.5% concentration. Whether this will be also thrue for the patients suffering pain ought to be determined.

scholarly journals Impact of the Sensory and Sympathetic Nervous System on Fracture Healing in Ovariectomized Mice

2020 ◽  
Vol 21 (2) ◽  
pp. 405 ◽  
Author(s):  
Tanja Niedermair ◽  
Rainer H. Straub ◽  
Christoph Brochhausen ◽  
Susanne Grässel
Keyword(s):  
Nervous System ◽  
Fracture Healing ◽  
Pain Threshold ◽  
Callus Tissue ◽  
Tissue Remodeling ◽  
Nerve Fibers ◽  
M2 Macrophage ◽  
Ovariectomized Mice ◽  
Bony Callus ◽  
Deficient Mice

The peripheral nervous system modulates bone repair under physiological and pathophysiological conditions. Previously, we reported an essential role for sensory neuropeptide substance P (SP) and sympathetic nerve fibers (SNF) for proper fracture healing and bone structure in a murine tibial fracture model. A similar distortion of bone microarchitecture has been described for mice lacking the sensory neuropeptide α-calcitonin gene-related peptide (α-CGRP). Here, we hypothesize that loss of SP, α-CGRP, and SNF modulates inflammatory and pain-related processes and also affects bone regeneration during fracture healing under postmenopausal conditions. Intramedullary fixed femoral fractures were set to 28 days after bilateral ovariectomy (OVX) in female wild type (WT), SP-, α-CGRP-deficient, and sympathectomized (SYX) mice. Locomotion, paw withdrawal threshold, fracture callus maturation and numbers of TRAP-, CD4-, CD8-, F4/80-, iNos-, and Arg1-positive cells within the callus were analyzed. Nightly locomotion was reduced in unfractured SP-deficient and SYX mice after fracture. Resistance to pressure was increased for the fractured leg in SP-deficient mice during the later stages of fracture healing, but was decreased in α-CGRP-deficient mice. Hypertrophic cartilage area was increased nine days after fracture in SP-deficient mice. Bony callus maturation was delayed in SYX mice during the later healing stages. In addition, the number of CD 4-positive cells was reduced after five days and the number of CD 8-positive cells was additionally reduced after 21 days in SYX mice. The number of Arg1-positive M2 macrophages was higher in α-CGRP-deficient mice five days after fracture. The alkaline phosphatase level was increased in SYX mice 16 days after fracture. Absence of α-CGRP appears to promote M2 macrophage polarization and reduces the pain threshold, but has no effect on callus tissue maturation. Absence of SP reduces locomotion, increases the pain-threshold, and accelerates hypertrophic callus tissue remodeling. Destruction of SNF reduces locomotion after fracture and influences bony callus tissue remodeling during the later stages of fracture repair, whereas pain-related processes are not affected.

scholarly journals Peripheral Mechanobiology of Touch—Studies on Vertebrate Cutaneous Sensory Corpuscles

2020 ◽  
Vol 21 (17) ◽  
pp. 6221 ◽  
Author(s):  
Ramón Cobo ◽  
Jorge García-Piqueras ◽  
Yolanda García-Mesa ◽  
Jorge Feito ◽  
Olivia García-Suárez ◽  
...  
Keyword(s):  
Ion Channels ◽  
Transient Receptor Potential ◽  
Receptor Potential ◽  
Transient Receptor Potential Channel ◽  
Mechanical Stimulus ◽  
Nerve Fibers ◽  
Current Data ◽  
Acid Sensing Ion Channels ◽  
Low Threshold ◽  
Transient Receptor

The vertebrate skin contains sensory corpuscles that are receptors for different qualities of mechanosensitivity like light brush, touch, pressure, stretch or vibration. These specialized sensory organs are linked anatomically and functionally to mechanosensory neurons, which function as low-threshold mechanoreceptors connected to peripheral skin through Aβ nerve fibers. Furthermore, low-threshold mechanoreceptors associated with Aδ and C nerve fibers have been identified in hairy skin. The process of mechanotransduction requires the conversion of a mechanical stimulus into electrical signals (action potentials) through the activation of mechanosensible ion channels present both in the axon and the periaxonal cells of sensory corpuscles (i.e., Schwann-, endoneurial- and perineurial-related cells). Most of those putative ion channels belong to the degenerin/epithelial sodium channel (especially the family of acid-sensing ion channels), the transient receptor potential channel superfamilies, and the Piezo family. This review updates the current data about the occurrence and distribution of putative mechanosensitive ion channels in cutaneous mechanoreceptors including primary sensory neurons and sensory corpuscles.

scholarly journals Acute effect of different concentrations of cayenne pepper cataplasm on sensory-motor functions and serum levels of inflammation-related biomarkers in healthy subjects

2018 ◽  
Vol 28 (1) ◽  
Author(s):  
Nejc Šarabon ◽  
Stefan Löfler ◽  
Jan Cvecka ◽  
Wolfgang Hübl ◽  
Sandra Zampieri
Keyword(s):  
Healthy Subjects ◽  
Serum Levels ◽  
Acute Effect ◽  
Mechanical Stimulus ◽  
Long Term Effects ◽  
Physical Medicine ◽  
Force Matching ◽  
Negative Side Effects ◽  
Underlying Mechanisms ◽  
Trunk Extension

Physical medicine therapies are often used in treating widespread musculoskeletal disorders, such as neck and low back pain. Herbal cataplasms containing rubefacient substances, such as Cayenne pepper, or galenic preparations like Munari cataplasm are commonly used as natural medications to treat painful areas. In this paper we show the effects of a 20-min application of Cayenne pepper and kaolin powder cataplasm (CPC) on healthy subjects. Treatment effects were evaluated by cold/hot feeling on visual analogue scale, blood pressure, body temperature, skin light touch sensations, two-point discrimination, and pain threshold to a mechanical stimulus, before and immediately after, 15 min after and 30 min after different concentration of Cayenne pepper in CPC preparation on healthy subjects. Maximal voluntary trunk extension force and trunk extension submaximal force matching error were also measured. In addition, the resulting optimal CPC mixture was tested for its safety by measuring changes in circulating levels of inflammatory-related biomarkers after 20-min application. The results indicate that the 5% concentration of Cayenne pepper in the preparation of CPC is the best choice, since no additional effects can be obtained with the 10% concentration, and the effects are higher than those observed at the 2.5% concentration. Importantly, 5% CPC application did not induce a significant increase of inflammatory-related biomarkers, suggesting that 20-min application has no negative side effects at systemic levels. Further studies are needed to investigate the immediate and long-term effects of repeated CPC applications as well as to understand the intersecting underlying mechanisms activated by Capsaicin and other identified factors, in order to be more extensively used in the field of physical medicine therapies.

Activity-Dependent Modulation of Axonal Excitability in Unmyelinated Peripheral Rat Nerve Fibers by the 5-HT(3) Serotonin Receptor

2006 ◽  
Vol 96 (6) ◽  
pp. 2963-2971 ◽  
Author(s):  
Philip M. Lang ◽  
Gila Moalem-Taylor ◽  
David J. Tracey ◽  
Hugh Bostock ◽  
Peter Grafe
Keyword(s):  
Action Potential ◽  
Conduction Velocity ◽  
Action Potentials ◽  
Serotonin Receptor ◽  
Nerve Fibers ◽  
Nerve Trunk ◽  
Axonal Membrane ◽  
Membrane Hyperpolarization ◽  
Axonal Excitability ◽  
Activity Dependent

Activity-dependent fluctuations in axonal excitability and changes in interspike intervals modify the conduction of trains of action potentials in unmyelinated peripheral nerve fibers. During inflammation of a nerve trunk, long stretches of axons are exposed to inflammatory mediators such as 5-hydroxytryptamine [5-HT]. In the present study, we have tested the effects of m-chlorophenylbiguanide (mCPBG), an agonist at the 5-HT(3) serotonin receptor, on activity- and potential-dependent variations in membrane threshold and conduction velocity of unmyelinated C-fiber axons of isolated rat sural nerve segments. The increase in axonal excitability during application of mCPBG was much stronger at higher frequencies of action potentials and/or during axonal membrane hyperpolarization. The effects on the postspike recovery cycle also depended on the rate of stimulation. At an action potential frequency of 1 Hz or in hyperpolarized axons, mCPBG produced a loss of superexcitability. In contrast, at 0.33 Hz, a small increase in the postspike subexcitability was observed. Similar effects on excitability changes were found when latency instead of threshold was recorded, but only at higher action potential frequencies: at 1.8 Hz, mCPBG increased conduction velocity and reduced postspike supernormality. The latter effect would increase the interspike interval if pairs of action potentials were conducted along several cm in an inflamed nerve trunk. These data indicate that activation of axonal 5-HT(3) receptors not only enhances membrane excitability but also modulates action potential trains in unmyelinated, including nociceptive, nerve fibers at high impulse rates.

scholarly journals Modulation and transmission of peripheral inputs in monkey cuneate and external cuneate nuclei

2011 ◽  
Vol 106 (5) ◽  
pp. 2764-2775 ◽  
Author(s):  
Claire L. Witham ◽  
Stuart N. Baker
Keyword(s):  
Peripheral Nerves ◽  
Action Potentials ◽  
Conditioning Stimulus ◽  
Mechanical Stimulus ◽  
Dorsal Column ◽  
Motor Threshold ◽  
Peripheral Stimulation ◽  
Transmission Of Information ◽  
Forelimb Afferents ◽  
Stimulation Of

Somatosensory signals undergo substantial modulation in the dorsal column nuclei. We examined transmission of signals from forelimb afferents in primate cuneate and external cuneate nuclei. In anesthetized macaque monkeys, the median, ulnar, deep radial, and superficial radial nerves were electrically stimulated at 1.5–2× motor threshold with independent Poisson trains whereas extracellular recordings were made from 317 cells. Responses to peripheral stimulation included instances of both brief facilitation and long lasting suppression. A high proportion of cells (87%) responded to stimulation of two or more peripheral nerves, suggesting a large amount of convergence. Facilitated cells showed coherence with the peripheral stimulation across a broad frequency range; coherence was especially high in cells that responded with a burst of action potentials. Cells that responded with suppression also showed significant coherence, but this fell rapidly for frequencies above 25 Hz. Similar results were seen in both the main and external cuneate. When stimulation of one nerve was conditioned by a preceding nerve stimulus, the response to the second stimulus was attenuated for around 40 ms. This occurred independently of whether the first stimulus produced an initial facilitation or suppression or whether the same or a different nerve served as a conditioning stimulus. Mechanical stimulation of a receptive field suppressed responses to a second identical mechanical stimulus over a similar timescale. We conclude that the primate cuneate nucleus is capable of transmitting temporal information about stimuli with high fidelity; stimuli interact both temporally and spatially to modulate the onward transmission of information.

An intracellular study of chemosensory fibers and endings

1980 ◽  
Vol 44 (6) ◽  
pp. 1077-1088 ◽  
Author(s):  
Y. Hayashida ◽  
H. Koyano ◽  
C. Eyzaguirre
Keyword(s):  
Carotid Body ◽  
Action Potentials ◽  
Physiological Saline ◽  
Mean Amplitude ◽  
Nerve Fibers ◽  
Chemical Stimulation ◽  
Nerve Terminals ◽  
Generator Potential ◽  
Single Nerve ◽  
Frequency Changes

1. The carotid body and its nerve, removed from anesthetized cats, were placed in physiological saline flowing under paraffin oil. The nerve, lifted into the oil, was used for either electrical stimulation or recording of the total afferent discharge. Intracellular recordings were obtained from individual nerve fibers and endings within the carotid body. The recording sites were identified by injecting Procion yellow through the intracellular electrodes; the tissues were then prepared for histology and observed with episcopic fluorescence or Nomarski optics. 2. Intracellularly recorded chemosensory fibers conducted at 1.1-30 m/s and usually displayed action potentials of regular amplitude. At times, however, some spikes become partially blocked while others maintained their original amplitude. "Natural" (hypoxia) or chemical (ACh or NaCN) stimulation induced different patterns of frequency changes of the large and small action potentials. This indicated nerve fiber branching at some distance from the recording site. 3. Intra- and extracellularly recorded spikes were blocked in 0 [Na+]0 by tetrodotoxin (TTX) or procaine. 4. During chemical stimulation, a slowly occurring depolarization (receptor or generator potential) was recorded intracellularly from the afferent fibers. It developed concomitantly with the increase in discharge. 5. Impalement of single nerve terminals (histologically identified) showed numerous "spontaneous" depolarizing potentials (SDPs) that had a mean amplitude of 5.6 mV, a mean duration of 46.1 ms, and nearly random distribution. They increased in frequency and summated during chemical stimulation. SDPs originated from either the site of recording or from neighboring areas. When the SDPs attained a certain amplitude, they seemed to give rise to action potentials. Also, relatively well developed or partially blocked spikes (apparently originating elsewhere) were recorded from single nerve terminals. 6. The receptor (generator) potential of chemosensory receptors appears to be an integrated response formed by multiple activity originating in different nerve endings.

Action Potentials From Single Auditory-Nerve Fibers?

Science ◽  
1948 ◽  
Vol 108 (2810) ◽  
pp. 513-513 ◽  
Author(s):  
R. GALAMBOS ◽  
H. DAVIS
Keyword(s):  
Auditory Nerve ◽  
Action Potentials ◽  
Nerve Fibers ◽  
Auditory Nerve Fibers

Taste Responsiveness of Fungiform Taste Cells With Action Potentials

2006 ◽  
Vol 96 (6) ◽  
pp. 3088-3095 ◽  
Author(s):  
Ryusuke Yoshida ◽  
Noriatsu Shigemura ◽  
Keisuke Sanematsu ◽  
Keiko Yasumatsu ◽  
Satoru Ishizuka ◽  
...  
Keyword(s):  
Action Potentials ◽  
Basolateral Membrane ◽  
Extracellular Recording ◽  
Hierarchical Cluster ◽  
Nerve Fibers ◽  
Chorda Tympani ◽  
Cell Responses ◽  
Single Receptor ◽  
Gustatory Nerve ◽  
Taste Cells

It is known that a subset of taste cells generate action potentials in response to taste stimuli. However, responsiveness of these cells to particular tastants remains unknown. In the present study, by using a newly developed extracellular recording technique, we recorded action potentials from the basolateral membrane of single receptor cells in response to taste stimuli applied apically to taste buds isolated from mouse fungiform papillae. By this method, we examined taste-cell responses to stimuli representing the four basic taste qualities (NaCl, Na saccharin, HCl, and quinine-HCl). Of 72 cells responding to taste stimuli, 48 (67%) responded to one, 22 (30%) to two, and 2 (3%) to three of four taste stimuli. The entropy value presenting the breadth of responsiveness was 0.158 ± 0.234 (mean ± SD), which was close to that for the nerve fibers (0.183 ± 0.262). In addition, the proportion of taste cells predominantly sensitive to each of the four taste stimuli, and the grouping of taste cells based on hierarchical cluster analysis, were comparable with those of chorda tympani (CT) fibers. The occurrence of each class of taste cells with different taste responsiveness to the four taste stimuli was not significantly different from that of CT fibers except for classes with broad taste responsiveness. These results suggest that information derived from taste cells generating action potentials may provide the major component of taste information that is transmitted to gustatory nerve fibers.

Electrical properties and synaptic connections to neurons in parasympathetic colonic ganglia of the cat

1984 ◽  
Vol 247 (1) ◽  
pp. G52-G61
Author(s):  
J. Krier ◽  
D. A. Hartman
Keyword(s):  
Synaptic Input ◽  
Action Potentials ◽  
Distal Colon ◽  
Nerve Fibers ◽  
Synaptic Connections ◽  
Electrophysiological Properties ◽  
Intracellular Injection ◽  
Spontaneous Action ◽  
Spontaneous Action Potentials

Intracellular recording techniques were used in vitro to analyze the electrophysiological properties and synaptic connections to cat parasympathetic neurons in ganglia located on the serosal surface of the distal colon. Neurons were classified into two types. The first type exhibited spontaneous action potentials at regular and irregular interspike intervals. Spontaneous action potentials were 1) not abolished by superfusion of the ganglia with a modified Krebs solution containing low Ca2+, high Mg2+, or nicotinic ganglionic blocking agents, 2) reduced or abolished by intracellular injection of hyperpolarizing current, and 3) increased by intracellular injection of depolarizing current. We suggest that the generation of spontaneous action potentials may be due to an endogenous depolarizing mechanism and not to cholinergic synaptic input from other neurons located in the ganglia. The second type of neuron termed "quiescent" exhibited a stable transmembrane potential and elicited action potentials in response to electrical stimulation of nerve trunks. Both quiescent and spontaneously discharging neurons receive synaptic input from preganglionic fibers in the pelvic nerve and project their postganglionic axons to colonic nerve fibers that innervate effector structures in the colon.

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