DOCSLIB.ORG

British Journal of Pharmacology, Submitted

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
British Journal of Pharmacology, Submitted View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Flinders Academic Commons Archived at the Flinders Academic Commons: http://dspace.flinders.edu.au/dspace/ This is the peer reviewed version of the following article: Nicholas, S., Yuan, S. Y., Brookes, S. J. H., Spencer, N. J., and Zagorodnyuk, V. P. (2017) Hydrogen peroxide preferentially activates capsaicin-sensitive high threshold afferents via TRPA1 channels in the guinea pig bladder. British Journal of Pharmacology, 174: 126–138. which has been published in final form at doi: 10.1111/bph.13661. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self- Archiving. 1 British Journal of Pharmacology Hydrogen peroxide preferentially activates capsaicin-sensitive high threshold afferents via TRPA1 channels in the guinea pig bladder S Nicholas1, S Y Yuan2, S J H Brookes1, N J Spencer1, and V P Zagorodnyuk1 1Discipline of Human Physiology & Centre for Neuroscience, Flinders University of South Australia, GPO Box 2100, Adelaide, South Australia 2Discipline of Anatomy and Histology & Centre for Neuroscience, Flinders University of South Australia, GPO Box 2100, Adelaide, South Australia Corresponding author Dr Vladimir Zagorodnyuk Discipline of Human Physiology, Flinders University GPO Box 2100, Adelaide, South Australia 5001 [email protected] tel: 61-8-8204-5238 fax: 61-8-8204-5768 Keywords: bladder, afferents, TRP channels, reactive oxygen species Abbreviations: AITC, allyl isothiocyanate (3-isothiocyanatoprop-1-ene); BCTC, 4-(3-chloro-2-pyridinyl)-N-[4- (1,1-dimethyl)phenyl]-1-piperazinecarboxamide; DRG, dorsal root ganglion: M8-B, N-(2- aminoethyl)-N-[[3-methoxy-4-(phenylmethoxy)phenyl]methyl]thiophene-2-carboxamide; NPPB, 5- nitro-2-[(3phenylpropyl)amino]benzoic acid; ROS, reactive oxygen species; TRP, transient receptor potential. Short title: Effects of H2O2 on bladder afferents 3504 words excluding Introduction, Methods, Figure legends and References 2 Table of Links TARGETS LIGANDS Ion channels BCTC HC-030031 TRPA1 Capsaicin H2O2 TRPM8 Capsazepine Icilin TRPV1 Deferoxamine AITC Dimethylthiourea M8-B Nicardipine NPPB These Tables list key protein targets and ligands in this article which are hyperlinked to corresponding entries in http://www.guidetopharmacology.org, the common portal for data from the IUPHAR/BPS Guide to PHARMACOLOGY (Pawson et al., 2014) and are permanently archived in the Concise Guide to PHARMACOLOGY (Alexander et al., 2015). 3 BACKGROUND AND PURPOSE There is increasing evidence suggesting that reactive oxygen species (ROS) play a major pathological role in bladder dysfunction induced by bladder inflammation and/or obstruction. The aim of this study was to determine the effect of H2O2 on different types of bladder afferents and its mechanism of action on sensory neurons in the guinea pig bladder. EXPERIMENTAL APPROACH “Close-to-target” single unit extracellular recordings were made from fine branches of pelvic nerves entering the guinea pig bladder, in flat sheet preparations, in vitro. KEY RESULTS H2O2 (300 - 1000 μM) preferentially and potently activated capsaicin-sensitive high threshold afferents but not low threshold stretch-sensitive afferents, which were only activated by significantly higher concentrations of hydrogen peroxide. The TRPV1 agonist, capsaicin excited 86% of high threshold afferents. The TRPA1 agonist, allyl isothiocyanate and the TRPM8 agonist, icilin activated 72% and 47% of capsaicin-sensitive high threshold afferents, respectively. The TRPA1 antagonist, HC-030031, but not the TRPV1 antagonist, capsazepine or the TRPM8 antagonist, M8-B, significantly inhibited the H2O2-induced activation of high threshold afferents. Dimethylthiourea and deferoxamine did not significantly change the effect of H2O2 on high threshold afferents. CONCLUSIONS AND IMPLICATIONS The findings show that H2O2, in the concentration range detected in inflammation or reperfusion after ischemia, evoked long-lasting activation of the majority of capsaicin-sensitive high threshold afferents, but not low threshold stretch-sensitive afferents. The data suggest that the TRPA1 channels located on these capsaicin-sensitive afferent fibres are probable targets of ROS released during oxidative stress. 4 Introduction It is well established that oxidative stress during tissue injury, ischemia and inflammation leads to - - generation of reactive oxygen species (ROS, such as O2 , OH , H2O2) which are released by polymorphonuclear neutrophils and macrophages, endothelial cells and smooth muscle cells (Swindlede et al., 2002; Yu et al., 2004; Saitoh et al., 2006; Allen & Bayraktutan, 2009). Increased production of ROS may contribute to a variety of pathologies such as bladder outlet obstruction, bladder overactivity and bladder dysfunction developed with age (Brading et al., 2004; Nomiya et al., 2012; Scheepee et al., 2011; Nochi et al., 2014). Sensory neurons, specialised for the detection of noxious endogenous stimuli and environmental irritants, employ a variety of specialised ion channels. Among them, the transient receptor potential (TRP) channel family is the largest group, consisting of six subfamilies of non-selective cation channels in mammals (Youshida et al., 2006; Miller and Zhang, 2011). A variety of TRP channels may be activated by free radicals. These include TRPA1, TRPV1, TRPV4, TRPC3-5, TRPM2, TRPM7 and TRPM8 channels (Yoshida et al., 2006; Andersson et al, 2008; Miller and Zhang, 2011; Naziroglu et al., 2013; Nocci et al., 2014). Numerous TRP channels are expressed by sensory neurons innervating the bladder, including TRPV1, TRPA1 and TRPM8 (Stein et al., 2004; Avelino & Cruz, 2006; Mukerji et al., 2006; Hayashi et al., 2011; La et al., 2011). TRPA1 channels are polymodal signal detectors which can act as mechanosensors, cool receptors and biosensors for large number of noxious endogenous and exogenous environmental agents (Hinman et al, 2006; Macpherson et al., 2007). In the rat bladder, TRPA1 is expressed in the urothelium, muscle layer and in TRPV1-positive sensory neurons (Du et al., 2007; Streng et al., 2008) while in the mouse and guinea pig bladder TRPA1 and TRPV1 are expressed in dorsal root ganglion (DRG) neurons but not in the urothelium (Everaerts et al., 2010; Skryma et al., 2011). The TRPV1 ion channel is also activated by polymodal stimuli, including capsaicin, noxious heat, low pH and some endogenous ligands, and has been strongly implicated in nociceptive signalling. Both TRPV1 and TRPA1 channels are co-expressed on DRG sensory neurons (Story et al., 2003). Recently, it has been proposed that TRPM8 channels in the urothelium may also serve as sensors in many conditions associated with high level of ROS (Nocchi et al., 2014). TRPM8 has been identified as a cold receptor since it is activated by both innocuous and noxious cool temperatures, and by compounds that evoke cooling sensations, such as menthol and icilin (Bautista et al., 2007). TRPM8 is expressed in Aδ and C fibre DRG neurons and is often co-expressed with TRPV1 (Story et al., 2003; Hayashi et al., 2009). In the bladder, it is expressed in both the urothelium and in sensory nerves (Stein et al., 2004; Mukerji et al., 2016; Hayashi et al., 2009). 5 Oxidative stress produced by application of H2O2 has been widely used to investigate the mechanism of action of ROS on sensory neurons. In the lung and heart, capsaicin-sensitive fibres were identified as primary targets for H2O2 acting via TRPV1 channels (Schultz and Ustinova, 1998; Ruan et al., 2005). However, in studies on isolated DRG neurons, it was shown that H2O2 acts via TRPA1 channels (Andersson et al., 2008; Sawada et al., 2008). Intravesically applied H2O2 (10- 100 mM) evoked bladder overactivity, most likely via an action on capsaicin-sensitive afferents (Masuda et al., 2007). A novel model of chronic inflammatory and overactive bladder utilises a single intravesical injection of H2O2 (Homan et al., 2013). It is still unclear which types of bladder sensory neurons are activated by free radicals and what are their major targets. The aim of this study was to determine the mechanism of action of H2O2 on the major types of bladder afferents. We have found that H2O2 was more potent in activating capsaicin-sensitive high threshold afferents in the bladder than low threshold stretch-sensitive afferents. H2O2 probably acts mostly via TRPA1 rather than TRPV1 or TRPM8 channels, located on the peripheral endings of capsaicin-sensitive high threshold afferents. Methods Animals. Adult Dunkin Hartley guinea pigs (N=123), weighing between 250 - 350 g, from a commercial vendor were used in the present study. Experiments were performed with animals maintained under 12 h light/dark cycles with free access to food and water. Animals were killed by overdose with isoflurane (5%) followed by cutting through the cervical spinal cord. All animal care, studies and procedures were approved by the Animal Welfare Committee of Flinders University and performed in accordance with guidance under the “Australian code of practice for the care and use of animals for scientific purposes” (8th edition, 2013) and the ARRIVE guidelines (Kilkenny et al., 2010), and the editorial on reporting animal studies (McGrath and Lilley, 2015). Guinea pigs were chosen for this study since we had previously characterised in detail the functional properties of different classes of sensory neurons in this species (Zagorodnyuk et al., 2007; 2009; 2010). Extracellular
Load more

Recommended publications
  • Effect of Capsaicin and Other Thermo-TRP Agonists on Thermoregulatory Processes in the American Cockroach
    Article Effect of Capsaicin and Other Thermo-TRP Agonists on Thermoregulatory Processes in the American Cockroach Justyna Maliszewska 1,*, Milena Jankowska 2, Hanna Kletkiewicz 1, Maria Stankiewicz 2 and Justyna Rogalska 1 1 Department of Animal Physiology, Faculty of Biology and Environmental Protection, Nicolaus Copernicus University, 87-100 Toruń, Poland; [email protected] (H.K.); [email protected] (J.R.) 2 Department of Biophysics, Faculty of Biology and Environmental Protection, Nicolaus Copernicus University, 87-100 Toruń, Poland; [email protected] (M.J.); [email protected] (M.S.) * Correspondence: [email protected]; Tel.: +48-56611-44-63 Academic Editor: Pin Ju Chueh Received: 5 November 2018; Accepted: 17 December 2018; Published: 18 December 2018 Abstract: Capsaicin is known to activate heat receptor TRPV1 and induce changes in thermoregulatory processes of mammals. However, the mechanism by which capsaicin induces thermoregulatory responses in invertebrates is unknown. Insect thermoreceptors belong to the TRP receptors family, and are known to be activated not only by temperature, but also by other stimuli. In the following study, we evaluated the effects of different ligands that have been shown to activate (allyl isothiocyanate) or inhibit (camphor) heat receptors, as well as, activate (camphor) or inhibit (menthol and thymol) cold receptors in insects. Moreover, we decided to determine the effect of agonist (capsaicin) and antagonist (capsazepine) of mammalian heat receptor on the American cockroach’s thermoregulatory processes. We observed that capsaicin induced the decrease of the head temperature of immobilized cockroaches. Moreover, the examined ligands induced preference for colder environments, when insects were allowed to choose the ambient temperature.
    [Show full text]
  • Photoswitchable Fatty Acids Enable Optical Control of TRPV1
    ARTICLE Received 18 Nov 2014 | Accepted 8 Apr 2015 | Published 22 May 2015 DOI: 10.1038/ncomms8118 OPEN Photoswitchable fatty acids enable optical control of TRPV1 James Allen Frank1, Mirko Moroni2, Rabih Moshourab2,3, Martin Sumser1, Gary R. Lewin2 & Dirk Trauner1 Fatty acids (FAs) are not only essential components of cellular energy storage and structure, but play crucial roles in signalling. Here we present a toolkit of photoswitchable FA analogues (FAAzos) that incorporate an azobenzene photoswitch along the FA chain. By modifying the FAAzos to resemble capsaicin, we prepare a series of photolipids targeting the Vanilloid Receptor 1 (TRPV1), a non-selective cation channel known for its role in nociception. Several azo-capsaicin derivatives (AzCAs) emerge as photoswitchable agonists of TRPV1 that are relatively inactive in the dark and become active on irradiation with ultraviolet-A light. This effect can be rapidly reversed by irradiation with blue light and permits the robust optical control of dorsal root ganglion neurons and C-fibre nociceptors with precision timing and kinetics not available with any other technique. More generally, we expect that photolipids will find many applications in controlling biological pathways that rely on protein–lipid interactions. 1 Department of Chemistry and Center for Integrated Protein Science, Ludwig Maximilians University Munich, Butenandtstrasse 5–13, Munich 81377, Germany. 2 Molecular Physiology of Somatic Sensation, Max Delbru¨ck Center for Molecular Medicine, Berlin 13125, Germany. 3 Department of Anesthesiology, Campus Charite´ Mitte und Virchow Klinikum, Charite´ Universita¨tsmedizin Berlin, Augustburgerplatz 1, Berlin 13353, Germany. Correspondence and requests for materials should be addressed to D.T.
    [Show full text]
  • Sensory and Signaling Mechanisms of Bradykinin, Eicosanoids, Platelet-Activating Factor, and Nitric Oxide in Peripheral Nociceptors
    Physiol Rev 92: 1699–1775, 2012 doi:10.1152/physrev.00048.2010 SENSORY AND SIGNALING MECHANISMS OF BRADYKININ, EICOSANOIDS, PLATELET-ACTIVATING FACTOR, AND NITRIC OXIDE IN PERIPHERAL NOCICEPTORS Gábor Peth˝o and Peter W. Reeh Pharmacodynamics Unit, Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Pécs, Pécs, Hungary; and Institute of Physiology and Pathophysiology, University of Erlangen/Nürnberg, Erlangen, Germany Peth˝o G, Reeh PW. Sensory and Signaling Mechanisms of Bradykinin, Eicosanoids, Platelet-Activating Factor, and Nitric Oxide in Peripheral Nociceptors. Physiol Rev 92: 1699–1775, 2012; doi:10.1152/physrev.00048.2010.—Peripheral mediators can contribute to the development and maintenance of inflammatory and neuropathic pain and its concomitants (hyperalgesia and allodynia) via two mechanisms. Activation Lor excitation by these substances of nociceptive nerve endings or fibers implicates generation of action potentials which then travel to the central nervous system and may induce pain sensation. Sensitization of nociceptors refers to their increased responsiveness to either thermal, mechani- cal, or chemical stimuli that may be translated to corresponding hyperalgesias. This review aims to give an account of the excitatory and sensitizing actions of inflammatory mediators including bradykinin, prostaglandins, thromboxanes, leukotrienes, platelet-activating factor, and nitric oxide on nociceptive primary afferent neurons. Manifestations, receptor molecules, and intracellular signaling mechanisms
    [Show full text]
  • Pleiotropic Pharmacological Actions of Capsazepine, a Synthetic Analogue of Capsaicin, Against Various Cancers and Inflammatory Diseases
    molecules Review Pleiotropic Pharmacological Actions of Capsazepine, a Synthetic Analogue of Capsaicin, against Various Cancers and Inflammatory Diseases Min Hee Yang 1, Sang Hoon Jung 1, Gautam Sethi 2,* and Kwang Seok Ahn 1,3,4,* 1 KHU-KIST Department of Converging Science and Technology, Kyung Hee University, Seoul 02447, Korea; [email protected] (M.H.Y.); [email protected] (S.H.J.) 2 Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117600, Singapore 3 Department of Science in Korean Medicine, Kyung Hee University, 24 Kyungheedae-ro, Dongdaemun-gu, Seoul 02447, Korea 4 Comorbidity Research Institute, College of Korean Medicine, Kyung Hee University, 24 Kyungheedae-ro, Dongdaemun-gu, Seoul 02447, Korea * Correspondence: [email protected] (G.S.); [email protected] (K.S.A.); Tel.: +65-6516-3267 (G.S.); +82-2-961-2316 (K.S.A.) Academic Editor: Roberto Fabiani Received: 18 February 2019; Accepted: 8 March 2019; Published: 12 March 2019 Abstract: Capsazepine is a synthetic analogue of capsaicin that can function as an antagonist of TRPV1. Capsazepine can exhibit diverse effects on cancer (prostate cancer, breast cancer, colorectal cancer, oral cancer, and osteosarcoma) growth and survival, and can be therapeutically used against other major disorders such as colitis, pancreatitis, malaria, and epilepsy. Capsazepine has been reported to exhibit pleiotropic anti-cancer effects against numerous tumor cell lines. Capsazepine can modulate Janus activated kinase (JAK)/signal transducer and activator of the transcription (STAT) pathway, intracellular Ca2+ concentration, and reactive oxygen species (ROS)-JNK-CCAAT/enhancer-binding protein homologous protein (CHOP) pathways.
    [Show full text]
  • TRP Channel Transient Receptor Potential Channels
    TRP Channel Transient receptor potential channels TRP Channel (Transient receptor potential channel) is a group of ion channels located mostly on the plasma membrane of numerous human and animal cell types. There are about 28 TRP channels that share some structural similarity to each other. These are grouped into two broad groups: Group 1 includes TRPC ("C" for canonical), TRPV ("V" for vanilloid), TRPM ("M" for melastatin), TRPN, and TRPA. In group 2, there are TRPP ("P" for polycystic) and TRPML ("ML" for mucolipin). Many of these channels mediate a variety of sensations like the sensations of pain, hotness, warmth or coldness, different kinds of tastes, pressure, and vision. TRP channels are relatively non-selectively permeable to cations, including sodium, calcium and magnesium. TRP channels are initially discovered in trp-mutant strain of the fruit fly Drosophila. Later, TRP channels are found in vertebrates where they are ubiquitously expressed in many cell types and tissues. TRP channels are important for human health as mutations in at least four TRP channels underlie disease. www.MedChemExpress.com 1 TRP Channel Antagonists, Inhibitors, Agonists, Activators & Modulators (-)-Menthol (E)-Cardamonin Cat. No.: HY-75161 ((E)-Cardamomin; (E)-Alpinetin chalcone) Cat. No.: HY-N1378 (-)-Menthol is a key component of peppermint oil (E)-Cardamonin ((E)-Cardamomin) is a novel that binds and activates transient receptor antagonist of hTRPA1 cation channel with an IC50 potential melastatin 8 (TRPM8), a of 454 nM. Ca2+-permeable nonselective cation channel, to 2+ increase [Ca ]i. Antitumor activity. Purity: ≥98.0% Purity: 99.81% Clinical Data: Launched Clinical Data: No Development Reported Size: 10 mM × 1 mL, 500 mg, 1 g Size: 10 mM × 1 mL, 5 mg, 10 mg, 25 mg, 50 mg, 100 mg (Z)-Capsaicin 1,4-Cineole (Zucapsaicin; Civamide; cis-Capsaicin) Cat.
    [Show full text]
  • Cough ? 5: the Type 1 Vanilloid Receptor: a Sensory Receptor for Cough
    257 REVIEW SERIES Thorax: first published as 10.1136/thx.2003.013482 on 25 February 2004. Downloaded from Cough ? 5: The type 1 vanilloid receptor: a sensory receptor for cough A H Morice, P Geppetti ............................................................................................................................... Thorax 2004;59:257–258. doi: 10.1136/thx.2003.013482 Evidence is presented to support the proposal that antagonist capsazepine has been found to inhibit both citric acid and capsaicin induced cough in activation of the type 1 vanilloid receptor (VR1) is an animals.7 Thus, both capsaicin and protons important sensory mechanism in cough. appear to be acting through a common pathway, ........................................................................... albeit at different allosteric sites. Recent advances in the understanding of the molecular activity of VR1 have indicated how these observations can be unified to produce a coher- ough is the commonest respiratory symp- ent description of a putative cough receptor. tom. According to the 1992 morbidity Cstatistics in general practice, acute ‘‘viral’’ cough accounts for the largest single cause of THE TYPE 1 VANILLOID RECEPTOR (VR1) new consultations with GPs with an annual VR1 has been cloned4 and is structurally related expenditure in 1999 of more than £200 million in to the transient receptor potential family of ion the UK, mostly on medicines which are, at best, channels. Rat VR1 consists of 432 amino acids poorly effective. Chronic cough arises from a and is predicted to have six transmembrane number of different pathologies and is a com- spanning domains. When expressed in cell lines mon and problematic source of referral to chest not containing constitutive vanilloid receptors, physicians. However, despite half a century of patch clamping studies have confirmed that it research, the pathophysiological mechanisms acts as a non-specific ion channel with similar causing cough are poorly understood.
    [Show full text]
  • TRPV1: Structure, Endogenous Agonists, and Mechanisms
    International Journal of Molecular Sciences Review TRPV1: Structure, Endogenous Agonists, and Mechanisms Miguel Benítez-Angeles, Sara Luz Morales-Lázaro, Emmanuel Juárez-González and Tamara Rosenbaum * Departamento de Neurociencia Cognitiva, División Neurociencias, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico; [email protected] (M.B.-A.); [email protected] (S.L.M.-L.); [email protected] (E.J.-G.) * Correspondence: [email protected]; Tel.: +52-555-622-56-24; Fax: +52-555-622-56-07 Received: 1 April 2020; Accepted: 29 April 2020; Published: 12 May 2020 Abstract: The Transient Receptor Potential Vanilloid 1 (TRPV1) channel is a polymodal protein with functions widely linked to the generation of pain. Several agonists of exogenous and endogenous nature have been described for this ion channel. Nonetheless, detailed mechanisms and description of binding sites have been resolved only for a few endogenous agonists. This review focuses on summarizing discoveries made in this particular field of study and highlighting the fact that studying the molecular details of activation of the channel by different agonists can shed light on biophysical traits that had not been previously demonstrated. Keywords: TRP channels; TRPV1; pain; agonist; structure 1. Introduction Since the Transient Receptor Potential Vanilloid 1 (TRPV1) ion channel was cloned in the last years of the 20th century [1], there have been extensive efforts to reveal the structural and functional details of this protein. Thus, nowadays it is one of the best characterized members of the TRP family of ion channels. TRPV1 is mainly expressed by trigeminal ganglion (TG) neurons and by small-diameter neurons within sensory ganglia such as the dorsal root ganglion (DRG).
    [Show full text]
  • The TRPM2 Ion Channel in Nucleotide-Gated Calcium Signaling
    The TRPM2 ion channel in nucleotide-gated calcium signaling Den Naturwissenschaftlichen Fakultäten der Friedrich-Alexander-Universität Erlangen-Nürnberg zur Erlangung des Doktorgrades vorgelegt von Ingo Lange aus Erlangen Als Dissertation genehmigt von den Naturwissen- schaftlichen Fakultäten der Universität Erlangen-Nürnberg Tag der mündlichen Prüfung: 14. Juli 2008 Vorsitzender der Prüfungskommission: Prof. Dr. Eberhart Bänsch Erstberichterstatter: Prof. Dr. Lars Nitschke Zweitberichterstatter: Prof. Dr. Andrea Fleig 2 3 TABLE OF CONTENT TABLE OF CONTENT....................................................................................................................................... 4 INTRODUCTION TO CALCIUM SIGNALING ........................................................................................... 6 CALCIUM AS A SECOND MESSENGER ................................................................................................................. 6 INFORMATION IS PROCESSED THROUGH CALCIUM–BINDING MOTIFS............................................................... 7 CALCIUM SIGNALING ACROSS THE PLASMA MEMBRANE .................................................................................. 7 CLASSICAL CALCIUM RELEASE CHANNELS ....................................................................................................... 8 INFORMATION THROUGH CALCIUM CAN BE MOBILIZED AND PROCESSED FROM DIFFERENT SOURCES ........... 8 CALCIUM SIGNALING IN THE COMPLEX NETWORK OF CELL SPECIFIC PHYSIOLOGY........................................
    [Show full text]
  • 9-Tetrahydrocannabinol and Cannabinol Activate Capsaicin-Sensitive Sensory Nerves Via a CB1 and CB2 Cannabinoid Receptor-Independent Mechanism
    The Journal of Neuroscience, June 1, 2002, 22(11):4720–4727 ⌬9-Tetrahydrocannabinol and Cannabinol Activate Capsaicin-Sensitive Sensory Nerves via a CB1 and CB2 Cannabinoid Receptor-Independent Mechanism Peter M. Zygmunt, David A. Andersson, and Edward D. Ho¨ gesta¨tt Department of Clinical Pharmacology, Institute of Laboratory Medicine, Lund University Hospital, SE-221 85 Lund, Sweden Although ⌬9-tetrahydrocannabinol (THC) produces analgesia, nerves is intact in vanilloid receptor subtype 1 gene knock-out its effects on nociceptive primary afferents are unknown. These mice. The THC response depends on extracellular calcium but neurons participate not only in pain signaling but also in the does not involve known voltage-operated calcium channels, local response to tissue injury. Here, we show that THC and glutamate receptors, or protein kinases A and C. These results cannabinol induce a CB1/CB2 cannabinoid receptor- may indicate the presence of a novel cannabinoid receptor/ion independent release of calcitonin gene-related peptide from channel in the pain pathway. capsaicin-sensitive perivascular sensory nerves. Other psych- otropic cannabinoids cannot mimic this action. The vanilloid Key words: calcitonin gene-related peptide; cannabinoids; receptor antagonist ruthenium red abolishes the responses to cannabinol; cannabis; capsaicin; nociceptors; pain; receptors, THC and cannabinol. However, the effect of THC on sensory sensory; tetrahydrocannabinol Marijuana contains a mixture of different cannabinoids, of which (CGRP) and substance P, in both the periphery and the spinal ⌬ 9-tetrahydrocannabinol (THC), the major psychoactive ingredi- cord (Holzer, 1992; Szallasi and Blumberg, 1999). In the vascu- ent, has been characterized extensively with regard to analgesic lature, this leads to vasodilatation and increased vascular perme- and anti-inflammatory effects (Mechoulam and Hanus, 2000; ability (Holzer, 1992).
    [Show full text]
  • Optical Assessment of Nociceptive TRP Channel Function at the Peripheral Nerve Terminal
    International Journal of Molecular Sciences Review Optical Assessment of Nociceptive TRP Channel Function at the Peripheral Nerve Terminal Fernando Aleixandre-Carrera 1 , Nurit Engelmayer 2,3, David Ares-Suárez 1, María del Carmen Acosta 1 , Carlos Belmonte 1, Juana Gallar 1,4,Víctor Meseguer 1,*,† and Alexander M. Binshtok 2,3,† 1 Instituto de Neurociencias, Universidad Miguel Hernández—CSIC, 03550 San Juan de Alicante, Spain; [email protected] (F.A.-C.); [email protected] (D.A.-S.); [email protected] (M.d.C.A.); [email protected] (C.B.); [email protected] (J.G.) 2 Department of Medical Neurobiology, Institute for Medical Research Israel—Canada, Hadassah School of Medicine, The Hebrew University, Jerusalem 91123, Israel; [email protected] (N.E.); [email protected] (A.M.B.) 3 The Edmond and Lily Safra Center for Brain Sciences, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel 4 Instituto de Investigación Sanitaria y Biomédica de Alicante, 03550 San Juan de Alicante, Spain * Correspondence: [email protected] † Shared last authorship. Abstract: Free nerve endings are key structures in sensory transduction of noxious stimuli. In spite of this, little is known about their functional organization. Transient receptor potential (TRP) channels have emerged as key molecular identities in the sensory transduction of pain-producing stimuli, yet the vast majority of our knowledge about sensory TRP channel function is limited to data obtained from in vitro models which do not necessarily reflect physiological conditions. In recent years, the development of novel optical methods such as genetically encoded calcium indicators and photo-modulation of ion channel activity by pharmacological tools has provided an invaluable Citation: Aleixandre-Carrera, F.; opportunity to directly assess nociceptive TRP channel function at the nerve terminal.
    [Show full text]
  • An Endogenous Capsaicin-Like Substance with High Potency at Recombinant and Native Vanilloid VR1 Receptors
    An endogenous capsaicin-like substance with high potency at recombinant and native vanilloid VR1 receptors Susan M. Huang*†, Tiziana Bisogno†‡, Marcello Trevisani†§, Abdulmonem Al-Hayani¶, Luciano De Petrocellis‡, Filomena Fezza‡, Michele Tognetto§, Timothy J. Petros*, Jocelyn F. Krey*, Constance J. Chu*, Jeffrey D. Millerʈ, Stephen N. Davies¶, Pierangelo Geppetti§, J. Michael Walker*, and Vincenzo Di Marzo‡** *Departments of Psychology and Neuroscience, Brown University, Providence, RI 02912; ‡Endocannabinoid Research Group, Institutes of Biomolecular Chemistry and Cybernetics, National Research Council, 80078 Pozzuoli, Napoli, Italy; §Department of Experimental and Clinical Medicine, University of Ferrara, 44100 Ferrara, Italy; ¶Department of Biomedical Sciences, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, United Kingdom; and ʈApplied Biosystems, Framingham, MA 01701 Edited by L. L. Iversen, University of Oxford, Oxford, United Kingdom, and approved April 18, 2002 (received for review April 3, 2002) The vanilloid receptor VR1 is a nonselective cation channel that is optimal functional interaction with the binding site (17, 18). Ac- most abundant in peripheral sensory fibers but also is found in cordingly, anandamide and lipoxygenase products (12–14) contain several brain nuclei. VR1 is gated by protons, heat, and the pungent the requisite acyl chain but lack the vanillyl group, hence their ingredient of ‘‘hot’’ chili peppers, capsaicin. To date, no endoge- relatively low potency at VR1. The only two metabolites found in nous compound with potency at this receptor comparable to that mammals that are similar structurally to vanillyl-amine are dopa- of capsaicin has been identified. Here we examined the hypothesis, mine and its 3-O-methyl derivative, homovanillyl-amine.
    [Show full text]
  • CHO & HEK-TRPM8 Tested on Qpatch
    Application Report CHO & HEK-TRPM8 tested on QPatch Pharmacological characteristics of two TRPM8 expressing cell lines by using multi-hole and single-hole technology on QPatch Summary CHO-TRPM8 and HEK-hTRPM8 cells were tested on QPatch which both provided high success rates, high-quality gigaseals and good recordings of the ion channel current. The EC50 and IC50 estimations for menthol, icilin and capsazepine were in agreement with reported literature values. Introduction TRPM8 belongs to the melastation family of transient receptor potential channels. The channel is cold - sensitive and non- Fig. 1. Representative IV plot of TRPM8 response to saline and racemic menthol selectively conducts mono- and di-valent cations. (‘reference’). An enlargement of the response at negative potentials is shown to the right. The channel is involved in physiological functions including Racemic menthol sensing of unpleasant cold, pain and thermoregulation but was Concentration-response relationships of racemic menthol were also found to be upregulated in pathophysiologies like cancer. recorded using a voltage ramp protocol. In the present work TRPM8 recombinantly expressed in Chinese Figure 2, 3 and 4 show representative raw traces, IT plot and Hill hamster ovary (CHO) and HEK293 cells were characterized using fit, respectively. Interestingly, racemic menthol did not elicit much QPatch. current at negative potentials. Results The IV relationship of the TRPM8 channel is shown in Figure 1. As expected, the channel exhibits strong outward rectification when activated with menthol (racemic menthol was used in Figure 1). This is in good accordance with what has been presented in the literature (1-4). Furthermore, application of racemic menthol generated a small inward current at negative potentials (Figure 1, insert).
    [Show full text]