6,279 results match your criteria neurons capsaicin

Activation of spinal dorsal horn astrocytes by noxious stimuli involves descending noradrenergic signaling.

Mol Brain 2021 May 10;14(1):79. Epub 2021 May 10.

Department of Molecular and System Pharmacology, Graduate School of Pharmaceutical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan.

Astrocytes are critical regulators of neuronal function in the central nervous system (CNS). We have previously shown that astrocytes in the spinal dorsal horn (SDH) have increased intracellular Ca levels following intraplantar injection of the noxious irritant, formalin. However, the underlying mechanisms remain unknown. Read More

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Plant Metabolites Drive Different Responses in Caterpillars of Two Closely Related Species.

Front Physiol 2021 21;12:662978. Epub 2021 Apr 21.

The Institute of Chemical Ecology and College of Plant Protection, Henan Agricultural University, Zhengzhou, China.

The host acceptances of insects can be determined largely by detecting plant metabolites using insect taste. In the present study, we investigated the gustatory sensitivity and feeding behaviors of two closely related caterpillars, the generalist (Hübner) and the specialist (Guenée), to different plant metabolites by using the single sensillum recording technique and the dual-choice assay, aiming to explore the contribution of plant metabolites to the difference of diet breadth between the two species. The results depicted that the feeding patterns of caterpillars for both plant primary and secondary metabolites were significantly different between the two species. Read More

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p70S6K on astrocytes protects dopamine neurons from 1-methyl-4-phenylpyridinium neurotoxicity.

Glia 2021 May 6. Epub 2021 May 6.

Department of Biochemistry and Molecular Biology, School of Medicine, Kyung Hee University, Seoul, South Korea.

Our recent finding has demonstrated that astrocytes confer neuroprotection by endogenously producing ciliary neurotrophic factor (CNTF) via transient receptor potential vanilloid 1 (TRPV1) in Parkinson's disease (PD). In this study, the possible molecular target for TRPV1-mediated CNTF production and its neuroprotective effects on dopamine neurons were further investigated. For comparison, glial cell-line derived neurotrophic factor (GDNF) was also examined. Read More

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Orexinergic descending inhibitory pathway mediates linalool odor-induced analgesia in mice.

Sci Rep 2021 Apr 29;11(1):9224. Epub 2021 Apr 29.

Department of Physiology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, 890-8544, Japan.

Linalool odor exposure induces an analgesic effect in mice. This effect disappeared in the anosmic model mice, indicating that olfactory input evoked by linalool odor triggered this effect. Furthermore, hypothalamic orexinergic neurons play a pivotal role in this effect. Read More

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Role of Primary Afferents in Arthritis Induced Spinal Microglial Reactivity.

Front Immunol 2021 7;12:626884. Epub 2021 Apr 7.

Comparative Biology and Experimental Medicine, University of Calgary, Calgary, AB, Canada.

Increased afferent input resulting from painful injury augments the activity of central nociceptive circuits both neuron-neuron and neuron-glia interactions. Microglia, resident immune cells of the central nervous system (CNS), play a crucial role in the pathogenesis of chronic pain. This study provides a framework for understanding how peripheral joint injury signals the CNS to engage spinal microglial responses. Read More

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The Calcium-Activated Chloride Channel TMEM16A is Inhibitied by Liquiritigenin.

Front Pharmacol 2021 8;12:628968. Epub 2021 Apr 8.

Department of Physiology, Showa University School of Medicine, Tokyo, Japan.

The transmembrane 16 (TMEM16) family contains 10 subtypes, and the function of each protein is different. TMEM16A is a calcium-activated chloride channel involved in physiological and pathological situations. Liquiritigenin is an aglycone derived from , and it is generated via the metabolism of enterobacterial flora. Read More

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Nociceptive receptors are expressed differently in trigeminal nociception after lingual nerve injury and unilateral external carotid artery occlusion in rats.

Arch Oral Biol 2021 Apr 16;126:105128. Epub 2021 Apr 16.

Faculty of Medicine, King Mongkut's Institute of Technology Ladkrabang, Bangkok, Thailand.

Objectives: To investigate the different changes in nociceptive activity between two animal models of trigeminal neuropathic pain: unilateral external carotid artery ischemic reperfusion and lingual nerve crush in rats.

Design: In this study, changes in nociceptive activity were investigated in unilateral external carotid artery ischemic reperfusion and lingual nerve crush models of trigeminal neuropathic pain in rats. Field excitatory postsynaptic potentials (fEPSPs) evoked by capsaicin application on the tongue of rats were recorded in the trigeminal nucleus caudalis. Read More

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Anti-nociceptive effects of oxytocin receptor modulation in healthy volunteers-A randomized, double-blinded, placebo-controlled study.

Eur J Pain 2021 Apr 21. Epub 2021 Apr 21.

Center for Sensory-Motor Interaction, Department of Health Science and Technology, Aalborg University, Aalborg, Denmark.

Background: There is increasing evidence for oxytocin as a neurotransmitter in spinal nociceptive processes. Hypothalamic oxytocinergic neurons project to the spinal dorsal horn, where they activate GABA-ergic inhibitory interneurons. The present study tested whether the long-acting oxytocin-analogue carbetocin has anti-nociceptive effects in multi-modal experimental pain in humans. Read More

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Different Sensitivity of action potential generation to the rate of depolarization in vagal afferent A-fiber versus C-fiber neurons.

Hui Sun

J Neurophysiol 2021 Apr 21. Epub 2021 Apr 21.

Medicine, Johns Hopkins University School of Medicine, United States.

The vagal afferent nerves innervate the visceral organs and convey sensory information from the internal environment to the central nervous system. A better understanding of the mechanisms controlling the activation of vagal afferent neurons bears physiological and pathological significance. Although it is generally believed that the magnitude and the rising rate of membrane depolarization are both critical for the action potential generation, no direct or quantitative evidence has been documented so far for the sensitivity of vagal afferent neuron activation to the rate of depolarization and for its underlying ionic mechanisms. Read More

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Lipopolysaccharides induce a RAGE-mediated sensitization of sensory neurons and fluid hypersecretion in the upper airways.

Sci Rep 2021 Apr 16;11(1):8336. Epub 2021 Apr 16.

Department of Anatomy, Physiology and Pharmacology (APP), College of Medicine, University of Saskatchewan, 107 Wiggins Road, Saskatoon, SK, S7N 5E5, Canada.

Thoracic dorsal root ganglia (tDRG) contribute to fluid secretion in the upper airways. Inflammation potentiates DRG responses, but the mechanisms remain under investigation. The receptor for advanced glycation end-products (RAGE) underlies potentiation of DRG responses in pain pathologies; however, its role in other sensory modalities is less understood. Read More

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Petasin and isopetasin reduce CGRP release from trigeminal afferents indicating an inhibitory effect on TRPA1 and TRPV1 receptor channels.

J Headache Pain 2021 Apr 13;22(1):23. Epub 2021 Apr 13.

Institute of Physiology and Pathophysiology, Friedrich-Alexander-University of Erlangen-Nürnberg, Universitätsstraße 17, 91054, Erlangen, Germany.

Background: Butterbur root extract with its active ingredients petasin and isopetasin has been used in the prophylactic treatment of migraine for years, while its sites of action are not completely clear. Calcitonin gene-related peptide (CGRP) is known as a biomarker and promoting factor of migraine. We set out to investigate the impact of petasins on the CGRP release from trigeminal afferents induced by activation of the calcium conducting transient receptor potential channels (TRPs) of the subtypes TRPA1 and TRPV1. Read More

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Effects of CGRP-Primed Dental Pulp Stem Cells on Trigeminal Sensory Neurons.

J Dent Res 2021 Apr 10:220345211004872. Epub 2021 Apr 10.

Department of Restorative Dentistry and Biomaterials Sciences, Harvard School of Dental Medicine, Boston, MA, USA.

Dental pulp stem cells (DPSCs) are important in tooth physiology, contributing to development, repair, regeneration, and immunomodulatory processes. However, their role in inflammatory mechanisms underlying pulpitis is not well understood. We evaluated the influence of DPSCs stimulated with calcitonin gene-related peptide (CGRP), a proinflammatory neuropeptide, on the expression of mediators released from DPSCs and the effect of these mediators on sensory neuron activity. Read More

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Surfactant cocamide monoethanolamide causes eye irritation by activating nociceptor TRPV1.

Br J Pharmacol 2021 Apr 10. Epub 2021 Apr 10.

State Key Laboratory of Natural Medicines and Department of TCM pharmacology, School of Traditional Pharmacy, China Pharmaceutical University, Nanjing, Jiangsu, China, 211198.

Background And Purpose: Cocamide monoethanolamide (CMEA) is commonly used as a surfactant-foam booster in cosmetic formulations. Upon contact with the eye or other sensitive skin areas, CMEA elicits sting and lasting irritation. We hypothesized a specific molecular interaction with TRPV1 by which CMEA caused eye irritation. Read More

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Ca Signalling Induced by NGF Identifies a Subset of Capsaicin-Excitable Neurons Displaying Enhanced Chemo-Nociception in Dorsal Root Ganglion Explants from Adult Mouse.

Int J Mol Sci 2021 Mar 4;22(5). Epub 2021 Mar 4.

International Centre for Neurotherapeutics, Dublin City University, Collins Avenue, D09 V209 Dublin, Ireland.

Nociceptors sense hazards via plasmalemmal cation channels, including transient receptor potential vanilloid 1 (TRPV1). Nerve growth factor (NGF) sensitises TRPV1 to capsaicin (CAPS), modulates nociceptor excitability and induces thermal hyperalgesia, but cellular mechanisms remain unclear. Confocal microscopy was used to image changes in intracellular Ca concentration ([Ca]) across neuronal populations in dorsal root ganglia (DRG) explants from adult mice, which express a fluorescent reporter in their sensory neurons. Read More

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Sex-dependent Cav2.3 channel contribution to the secondary hyperalgesia in a mice model of central sensitization.

Brain Res 2021 Mar 19;1764:147438. Epub 2021 Mar 19.

Programa de Pós-graduação em Farmacologia, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil. Electronic address:

Central sensitization (CS) is characteristic of difficult to treat painful conditions, such as fibromyalgia and neuropathies and have sexual dimorphism involved. The calcium influx in nociceptive neurons is a key trigger for CS and the role of Cav2.1 and Cav2. Read More

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CB2 cannabinoid receptor agonist selectively inhibits the mechanosensitivity of mucosal afferents in the guinea pig bladder.

Am J Physiol Renal Physiol 2021 05 22;320(5):F859-F865. Epub 2021 Mar 22.

Discipline of Human Physiology, Flinders Health & Medical Research Institute, College of Medicine and Public Health, Flinders University, Adelaide, South Australia, Australia.

Bladder afferents play a pivotal role in bladder function such as urine storage and micturition as well as conscious sensations such as urgency and pain. Endocannabinoids are ligands of cannabinoid 1 and 2 (CB1 and CB2) receptors but can influence the activity of a variety of G protein-coupled receptors as well as ligand-gated and voltage-gated channels. It is still not known which classes of bladder afferents are influenced by CB1 and CB2 receptor agonists. Read More

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Impact of Hepatoma-Derived Growth Factor Blockade on Resiniferatoxin-Induced Neuropathy.

Neural Plast 2021 27;2021:8854461. Epub 2021 Feb 27.

Division of Neurosurgery, Department of Surgery, Kaohsiung Medical University Hospital, Kaohsiung 807, Taiwan.

Resiniferatoxin is an ultrapotent capsaicin analog that mediates nociceptive processing; treatment with resiniferatoxin can cause an inflammatory response and, ultimately, neuropathic pain. Hepatoma-derived growth factor, a growth factor related to normal development, is associated with neurotransmitters surrounding neurons and glial cells. Therefore, the study aims to investigate how blocking hepatoma-derived growth factor affects the inflammatory response in neuropathic pain. Read More

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February 2021

TRPV1 Activation Promotes β-arrestin2 Interaction with the Ribosomal Biogenesis Machinery in the Nucleolus:Implications for p53 Regulation and Neurite Outgrowth.

Int J Mol Sci 2021 Feb 25;22(5). Epub 2021 Feb 25.

Department of Physiology and Pharmacology, Inflammation Research Network-Snyder Institute for Chronic Diseases and Alberta Children's Hospital Research Institute, University of Calgary, 3330 Hospital Dr NW, Calgary, AB T2N 1N4, Canada.

Transient receptor potential vanilloids TRPV1) are non-selective cation channels that sense and transduce inflammatory pain signals. We previously reported that activation of TRPV1 induced the translocation of β-arrestin2 (ARRB2) from the cytoplasm to the nucleus, raising questions about the functional role of ARRB2 in the nucleus. Here, we determined the ARRB2 nuclear signalosome by conducting a quantitative proteomic analysis of the nucleus-sequestered L395Q ARRB2 mutant, compared to the cytosolic wild-type ARRB2 (WT ARRB2), in a heterologous expression system. Read More

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February 2021

Effects of morphine preconditioning on TRPV1 sensitization and ERK1/2 phosphorylation induced by TGFβ1 in neurocytes.

Neuroreport 2021 Mar;32(5):339-344

Department of Anesthesiology, Division of Life Sciences and Medicine, The First Affiliated Hospital of USTC, University of Science and Technology of China, Hefei, Anhui, China.

Objective: Myocardium ischemia-reperfusion injury (IRI) is the major cause of cardiac dysfunction. While intrathecal morphine preconditioning (MPC) can alleviate IRI in animal model, the molecular processes underlying IRI and MPC remain elusive. This study aims to test whether pretreatment with morphine can ameliorate the increased activity of transient receptor potential vanilloid 1 (TRPV1) induced by transforming growth beta1 (TGFβ1) in cultured dorsal root ganglion neurons as a model of the effects of cardiac ischemia on nociceptive primary afferent neurons. Read More

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How do neurons in sensory ganglia communicate with satellite glial cells?

Brain Res 2021 Jun 22;1760:147384. Epub 2021 Feb 22.

Laboratory of Experimental Surgery, Hadassah-Hebrew University Medical Center, Mount Scopus, Jerusalem 91240, Israel; Faculty of Medicine, Hebrew University of Jerusalem, Israel. Electronic address:

Neurons and satellite glial cells (SGCs) in sensory ganglia maintain bidirectional communications that are believed to be largely mediated by chemical messengers. Nerve injury leads to SGC activation, which was proposed to be mediated by nitric oxide (NO) released from active neurons, but evidence for this is lacking. Here we tested the idea that increased neuronal firing is a major factor in NO release. Read More

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Extracellular vesicle-encapsulated microRNA-23a from dorsal root ganglia neurons binds to A20 and promotes inflammatory macrophage polarization following peripheral nerve injury.

Aging (Albany NY) 2021 02 17;13(5):6752-6764. Epub 2021 Feb 17.

Department of Neurology, Affiliated Hospital of Chengdu University, Chengdu 610081, P.R. China.

Extracellular vesicles (EVs) are capable of transferring microRNAs (miRNAs or miRs) between two different types of cells and also serve as vehicles for delivery of therapeutic molecules. After peripheral nerve injury, abnormal expression patterns of miRNAs have been observed in dorsal root ganglia (DRG) sensory neurons. We hypothesized that sensory neurons secrete miRs-containing EVs to communicate with macrophages. Read More

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February 2021

Beyond Neuronal Heat Sensing: Diversity of TRPV1 Heat-Capsaicin Receptor-Channel Functions.

Yaroslav M Shuba

Front Cell Neurosci 2020 5;14:612480. Epub 2021 Feb 5.

Bogomoletz Institute of Physiology, National Academy of Sciences of Ukraine, Kyiv, Ukraine.

Transient receptor potential vanilloid 1 (TRPV1) is a calcium-permeable ion channel best known for its ability to be gated by the pungent constituent of red chili pepper, capsaicin, and related chemicals from the group of vanilloids as well as by noxious heat. As such, it is mostly expressed in sensory neurons to act as a detector of painful stimuli produced by pungent chemicals and high temperatures. Its activation is also sensitized by the numerous endogenous inflammatory mediators and second messengers, making it an important determinant of nociceptive signaling. Read More

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February 2021

Analgesic Effects of Lipid Raft Disruption by Sphingomyelinase and Myriocin via Transient Receptor Potential Vanilloid 1 and Transient Receptor Potential Ankyrin 1 Ion Channel Modulation.

Front Pharmacol 2020 27;11:593319. Epub 2021 Jan 27.

Deparment of Pharmacology and Pharmacotherapy, University of Pécs, Medical School, Pécs, Hungary.

Transient Receptor Potential (TRP) Vanilloid 1 and Ankyrin 1 (TRPV1, TRPA1) cation channels are expressed in nociceptive primary sensory neurons, and integratively regulate nociceptor and inflammatory functions. Lipid rafts are liquid-ordered plasma membrane microdomains rich in cholesterol, sphingomyelin and gangliosides. We earlier showed that lipid raft disruption inhibits TRPV1 and TRPA1 functions in primary sensory neuronal cultures. Read More

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January 2021

Injectable Capsaicin for the Management of Pain Due to Osteoarthritis.

Molecules 2021 Feb 3;26(4). Epub 2021 Feb 3.

Translational Research in Pain (TRiP) Program, Comparative Pain Research and Education Centre, Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC 27606, USA.

Capsaicin is a potent agonist of the TRPV1 channel, a transduction channel that is highly expressed in nociceptive fibers (pain fibers) throughout the peripheral nervous system. Given the importance of TRPV1 as one of several transduction channels in nociceptive fibers, much research has been focused on the potential therapeutic benefits of using TRPV1 antagonists for the management of pain. However, an antagonist has two limitations. Read More

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February 2021

Cross-effect of TRPV1 and EP3 receptor on coughs and bronchopulmonary C-neural activities.

PLoS One 2021 2;16(2):e0246375. Epub 2021 Feb 2.

Pathophysiology Program, Lovelace Biomedical Research Institute, Albuquerque, New Mexico, United States of America.

Prostaglandin E2 (PGE2)-induced coughs in vivo and vagal nerve depolarization in vitro are inhibited by systemic and local administration of prostaglandin EP3 receptor (L-798106) and TRPV1 antagonists (JNJ 17203212). These results indicate a modulating effect of TRPV1 on the EP3 receptor-mediated cough responses to PGE2 likely through the vagal sensory nerve. This study aimed to determine whether 1) inhalation of aerosolized JNJ 17203212 and L-798106 affected cough responses to citric acid (CA, mainly stimulating TRPV1) and PGE2; 2) TRPV1 and EP3 receptor morphologically are co-expressed and electrophysiologically functioned in the individual of vagal pulmonary C-neurons (cell bodies of bronchopulmonary C-fibers in the nodose/jugular ganglia); and 3) there was a cross-effect of TRPV1 and EP3 receptor on these neural excitations. Read More

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February 2021

TRESK background potassium channel modifies the TRPV1-mediated nociceptor excitability in sensory neurons.

Cephalalgia 2021 Feb 1:333102421989261. Epub 2021 Feb 1.

Department of Physiology, Faculty of Medicine, Semmelweis University, Budapest, Hungary.

Background: TWIK-related spinal cord potassium channel (TRESK) background potassium channels have a key role in controlling resting membrane potential and excitability of sensory neurons. A frameshift mutation leading to complete loss of TRESK function has been identified in members of a family suffering from migraine with aura. In the present study, we examined the role of TRESK channels on nociceptor function in mice. Read More

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February 2021

Antidromic Spike Propagation and Dissimilar Expression of P2X, 5-HT, and TRPV1 Channels in Peripheral vs. Central Sensory Axons in Meninges.

Front Cell Neurosci 2020 15;14:623134. Epub 2021 Jan 15.

Department of Human and Animal Physiology, Institute of Fundamental Medicine and Biology, Kazan Federal University, Kazan, Russia.

The terminal branches of the trigeminal nerve in meninges are supposed to be the origin site of migraine pain. The main function of these peripheral sensory axons is the initiation and propagation of spikes in the orthodromic direction to the second order neurons in the brainstem. The stimulation of the trigeminal ganglion induces the release of the neuropeptide CGRP in meninges suggesting the antidromic propagation of excitation in these fibers. Read More

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January 2021

Reactivity of astrocytes in hippocampal CA1 area in rats after administration of habanero peppers.

Folia Histochem Cytobiol 2021 27;59(1):1-7. Epub 2021 Jan 27.

Faculty of Biological and Veterinary Sciences, Nicolaus Copernicus University in Torun, Gagarina 7, 87-100 Toruń, Poland.

Introduction: Astrocytes react to microenvironmental changes. Their reactivity is manifested by an increase in glial fibrillary acidic protein (GFAP) and S100b protein levels, hypertrophy and hyperplasia. The aim of the study was to analyse immunoreactive GFAP (GFAP-IR) and S100b (S100b-IR) astrocytes of hippocampal CA1 area in adult rats intragastrically (i. Read More

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January 2021

The role of pruriceptors in enhancing sensitivity to pruritogens in a murine chronic compression model of dorsal root ganglion.

Mol Brain 2021 01 19;14(1):15. Epub 2021 Jan 19.

Institute of Basic Medical Sciences, Neuroscience Center, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, 100005, China.

Chronic pruritus is a symptom that commonly observed in neurological diseases. It has been hypothesized that the chronic pruritus may result from sensitization of itch-signaling pathways but the mechanisms remain obscure. In this study, we established a mouse model of chronic compression of dorsal root ganglion (CCD) and injected various pruritogenic and algogenic agents intradermally to the calf skin ipsilateral to the compressed dorsal root ganglion (DRG). Read More

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January 2021

Dietary capsaicin normalizes CGRP peptidergic DRG neurons in experimental diabetic peripheral neuropathy.

Sci Rep 2021 Jan 18;11(1):1704. Epub 2021 Jan 18.

Department of Anesthesiology, Second Hospital of Shanxi Medical University, 382 Wuyi Road, Taiyuan, 030001, Shanxi, China.

Diabetic sensory neuropathy leads to impairment of peripheral sensory nerves and downregulation of calcitonin gene-related peptide (CGRP) in a functionally specific subset of peripheral sensory neurons mediating pain. Whether CGRP plays a neuroprotective role in peripheral sensory nerve is unclear. We evaluated alterations in noxious thermal sensation and downregulation of CGRP in the 8 weeks after induction of diabetes in rats. Read More

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January 2021