Tags

Type your tag names separated by a space and hit enter

Comparison of icilin- and cold-evoked responses of spinal neurones, and their modulation of mechanical activity, in a model of neuropathic pain.
Brain Res. 2008 Jun 18; 1215:87-96.BR

Abstract

Cold allodynia is a poorly understood symptom of neuropathic pain. Two members of the transient receptor potential (TRP) family of proteins, TRPM8 and TRPA1, may contribute to cold somatosensation. The aim of the present study was to investigate the usefulness of icilin as a pharmacological tool to study primary afferent fibre responses to cold stimuli and to determine whether there are differences in the responses of spinal neurones to cooling of peripheral receptive fields in control versus neuropathic rats. The effects of icilin, a TRPM8 and TRPA1 agonist, on intracellular Ca(2+) ([Ca(2+)](i)) responses of small diameter adult dorsal root ganglia (DRG) neurones were determined. Icilin (10 nM-10 microM) produced a concentration-related increase in [Ca(2+)](i) in DRG neurones, which was attenuated by the non-selective TRP channel antagonist ruthenium red (10 microM). In vivo electrophysiology in naïve, sham-operated and SNL rats demonstrated that application of ice to receptive fields evoked firing of wide dynamic range (WDR) neurones, which was significantly greater in SNL rats than naïve and sham-operated rats. Intraplantar injection of icilin did not evoke firing of WDR neurones in naïve, sham-operated or SNL rats but inhibited mechanically-evoked responses of WDR neurones in naïve and sham-operated rats, whilst facilitating mechanically-evoked responses in SNL rats. Icilin increased both innocuous (sham-operated and SNL rats) and noxious (SNL rats) receptive field sizes of WDR neurones. Our data suggests that icilin modulates the mechanosensitivity of dorsal horn neurones. The differing effects of ice and icilin on dorsal horn neurones indicate different mechanisms of action.

Authors+Show Affiliations

Institute of Neuroscience, School of Biomedical Sciences, E-floor, Medical School, Queens Medical Centre, University of Nottingham, Nottingham, NG7 2UH, UK. jlm33@le.ac.ukNo affiliation info availableNo affiliation info available

Pub Type(s)

Comparative Study
Journal Article

Language

eng

PubMed ID

18479674

Citation

Brignell, Jennifer L., et al. "Comparison of Icilin- and Cold-evoked Responses of Spinal Neurones, and Their Modulation of Mechanical Activity, in a Model of Neuropathic Pain." Brain Research, vol. 1215, 2008, pp. 87-96.
Brignell JL, Chapman V, Kendall DA. Comparison of icilin- and cold-evoked responses of spinal neurones, and their modulation of mechanical activity, in a model of neuropathic pain. Brain Res. 2008;1215:87-96.
Brignell, J. L., Chapman, V., & Kendall, D. A. (2008). Comparison of icilin- and cold-evoked responses of spinal neurones, and their modulation of mechanical activity, in a model of neuropathic pain. Brain Research, 1215, 87-96. https://doi.org/10.1016/j.brainres.2008.03.072
Brignell JL, Chapman V, Kendall DA. Comparison of Icilin- and Cold-evoked Responses of Spinal Neurones, and Their Modulation of Mechanical Activity, in a Model of Neuropathic Pain. Brain Res. 2008 Jun 18;1215:87-96. PubMed PMID: 18479674.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Comparison of icilin- and cold-evoked responses of spinal neurones, and their modulation of mechanical activity, in a model of neuropathic pain. AU - Brignell,Jennifer L, AU - Chapman,Victoria, AU - Kendall,David A, Y1 - 2008/04/09/ PY - 2007/10/12/received PY - 2008/03/27/revised PY - 2008/03/27/accepted PY - 2008/5/16/pubmed PY - 2008/9/5/medline PY - 2008/5/16/entrez SP - 87 EP - 96 JF - Brain research JO - Brain Res VL - 1215 N2 - Cold allodynia is a poorly understood symptom of neuropathic pain. Two members of the transient receptor potential (TRP) family of proteins, TRPM8 and TRPA1, may contribute to cold somatosensation. The aim of the present study was to investigate the usefulness of icilin as a pharmacological tool to study primary afferent fibre responses to cold stimuli and to determine whether there are differences in the responses of spinal neurones to cooling of peripheral receptive fields in control versus neuropathic rats. The effects of icilin, a TRPM8 and TRPA1 agonist, on intracellular Ca(2+) ([Ca(2+)](i)) responses of small diameter adult dorsal root ganglia (DRG) neurones were determined. Icilin (10 nM-10 microM) produced a concentration-related increase in [Ca(2+)](i) in DRG neurones, which was attenuated by the non-selective TRP channel antagonist ruthenium red (10 microM). In vivo electrophysiology in naïve, sham-operated and SNL rats demonstrated that application of ice to receptive fields evoked firing of wide dynamic range (WDR) neurones, which was significantly greater in SNL rats than naïve and sham-operated rats. Intraplantar injection of icilin did not evoke firing of WDR neurones in naïve, sham-operated or SNL rats but inhibited mechanically-evoked responses of WDR neurones in naïve and sham-operated rats, whilst facilitating mechanically-evoked responses in SNL rats. Icilin increased both innocuous (sham-operated and SNL rats) and noxious (SNL rats) receptive field sizes of WDR neurones. Our data suggests that icilin modulates the mechanosensitivity of dorsal horn neurones. The differing effects of ice and icilin on dorsal horn neurones indicate different mechanisms of action. SN - 0006-8993 UR - https://www.unboundmedicine.com/medline/citation/18479674/Comparison_of_icilin__and_cold_evoked_responses_of_spinal_neurones_and_their_modulation_of_mechanical_activity_in_a_model_of_neuropathic_pain_ L2 - https://linkinghub.elsevier.com/retrieve/pii/S0006-8993(08)00817-2 DB - PRIME DP - Unbound Medicine ER -