Introduction: In this study we validated a modified laser Doppler imager method (mLDIf) for assessing C-fiber function and compared it to the original (oLDIf). Both measure flare size in foot skin after heating, but the mLDIf uses 47°C (vs. 44°C), making it quicker and better suited for clinical use.
Methods: To confirm that mLDIf assesses C-fiber function, 5 healthy controls (HC) were studied before and after local anesthesia (LA). Reproducibility and comparison with oLDIf was assessed in HC (n = 16). Finally, diabetes subjects with (DN(+), n = 10) and without (DN(-), n = 16) neuropathy were studied.
Results: LA almost abolished the flare (9.3 ± 3.0 cm(2) vs. 1.7 ± 0.3 cm(2), P < 0.0001). mLDIf produced larger flares (9.9 ± 3.4 vs. 5.7 ± 2.3 cm(2), P < 0.0001), but correlated with oLDIf (r = 0.81, P < 0.001). mLDIf was reduced in DN(-) (6.8 ± 2.8 vs. HC, P = 0.003), markedly so in DN(+) (2.0 ± 1.1 vs. HC and DN(-), P < 0.0001).
Conclusion: The mLDIf is a quick, practical method for assessing C-fiber function in the clinical setting.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1002/mus.23532 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
In vivo calcium imaging reveals directional sensitivity of C-low threshold mechanoreceptors.
J Physiol
January 2025
School of Life Sciences, The University of Nottingham, Queen's Medical Centre, Nottingham, UK.
C-low threshold mechanoreceptors (C-LTMRs) in animals (termed C-tactile (CT) fibres in humans) are a subgroup of C-fibre primary afferents, which innervate hairy skin and respond to low-threshold punctate indentations and brush stimuli. These afferents respond to gentle touch stimuli and are implicated in mediating pleasant/affective touch. These afferents have traditionally been studied using low-throughput, technically challenging approaches, including microneurography in humans and teased fibre electrophysiology in other mammals.
View Article and Find Full Text PDFSmall fiber pathology in fibromyalgia syndrome.
Pain Rep
February 2025
Department of Neurology, University Hospital Würzburg, Würzburg, Germany.
About 50% of women with fibromyalgia syndrome have reduced skin innervation. This finding is consistent in patient cohorts from different regions of the world. Small fiber function may also be affected, as shown by various studies using different methods, such as quantitative sensory testing or special small fiber neurophysiology such as C-fiber microneurography.
View Article and Find Full Text PDFValidation of the Histamine- and Heat-Induced Axon-Reflex Flare Response in a Nonselected Population of People With Type 1 Diabetes.
Muscle Nerve
February 2025
Steno Diabetes Center North Denmark, Aalborg University Hospital, Aalborg, Denmark.
Introduction/aims: Diabetic peripheral neuropathy affects small nerve fibers early, but adequate evaluation has proven difficult. One method for functional assessment of small nerve fiber function is the axon-reflex flare (ARF) response. This study aimed to 1) validate the histamine-induced ARF response in a nonselected population with diabetes, 2) compare the response to that induced by local heating, and 3) compare both methods to an established method (quantitative sensory testing) in a nonselected population with diabetes.
View Article and Find Full Text PDFEarly life stress modulates neonatal somatosensation and the transcriptional profile of immature sensory neurons.
Pain
September 2024
Molecular, Cellular and Biochemical Pharmacology Graduate Program, University of Cincinnati College of Medicine, Cincinnati, OH, United States.
Early life stress (ELS) is associated with an increased risk of experiencing chronic pain during adulthood, but surprisingly little is known about the short-term influence of ELS on nociceptive processing in the immature nervous system and the concomitant effects on somatosensation in the neonate. Here, we investigate how ELS modulates pain in neonatal mice and the transcriptional and electrophysiological signatures of immature dorsal root ganglia (DRG). Shortly after the administration of a neonatal limiting bedding (NLB) paradigm from postnatal days (P)2 to P9, both male and female pups exhibited robust hypersensitivity in response to tactile, pressure, and noxious cold stimuli compared with a control group housed under standard conditions, with no change in their sensitivity to noxious heat.
View Article and Find Full Text PDFActivation of mouse skin mast cells and cutaneous afferent C-fiber subtypes by bee venom.
Neurosci Lett
January 2025
Division of Allergy and Clinical Immunology, Department of Medicine, Johns Hopkins University School of Medicine, 5501 Hopkins Bayview Cir, Baltimore, MD 21224, USA. Electronic address:
In mammals, many Hymenopteran stings are characterized by pain, redness, and swelling - three manifestations consistent with nociceptive nerve fiber activation. The effect of a Western honeybee (Apis mellifera) venom on the activation of sensory C-fibers in mouse skin was studied using an innervated isolated mouse skin preparation that allows for intra-arterial delivery of chemicals to the nerve terminals in the skin. Our data show that honeybee venom stimulated mouse cutaneous nociceptive-like C-fibers, with an intensity (action potential discharge frequency) similar to that seen with a maximally-effective concentration of capsaicin.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!