51
|
Abstract
Effects of C-fiber activation on type I slowly adapting mechanoreceptor responses were investigated in a rat in vitro nerve-skin preparation using controlled mechanical stimuli. Two changes in behavior were evoked by antidromic C-fiber stimulation: (1). The type I response to mechanical stimuli was modulated in a graded fashion by antidromic C-fiber activation. The average decrease in mechanoresponse from baseline discharge was 53% at 20-Hz, 51% at 5-Hz, and 30% at 1-Hz stimulation rate. The type I response recovered to baseline levels following termination of antidromic electrical stimulation. (2). Antidromic C-fiber activation generated a spontaneous ongoing activity in many skin units; this was independent of mechanical stimulation and outlasted electrical stimulation. The fact that neither antidromic electrical stimulation of the crushed nerve trunk nor selective A-fiber activation elicited these reactions suggests that they were mediated via action potentials of slowly conducting (C-fiber) axons. Immunohistochemical staining revealed both substance P- and calcitonin gene-related peptide-like immunoreactivity in small unmyelinated nerve fibers entering the touch dome. These results support the concepts that (1). the type I slowly adapting mechanoreceptor in rat receives input from nociceptive terminals within the touch dome. (2). The function of type I slowly adapting mechanoreceptors is modulated by axon reflex activation of nociceptor terminals, which may play a role in altering the type I response during states of mechanical allodynia and have paracrine and autocrine influences on maintenance of touch dome structure.
Collapse
Affiliation(s)
- J Zhang
- Department of Physiology, University of Utah School of Medicine, 410 Chipeta Way, Room 156, Salt Lake City, UT 84108-1297, USA
| | | | | |
Collapse
|
52
|
Sarkar S, Hobson AR, Hughes A, Growcott J, Woolf CJ, Thompson DG, Aziz Q. The prostaglandin E2 receptor-1 (EP-1) mediates acid-induced visceral pain hypersensitivity in humans. Gastroenterology 2003; 124:18-25. [PMID: 12512025 DOI: 10.1053/gast.2003.50022] [Citation(s) in RCA: 93] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
BACKGROUND & AIMS Central sensitization, an activity-dependent increase in spinal cord neuronal excitability, has been shown to contribute to esophageal pain hypersensitivity. Prostaglandin E2 (PGE(2)) is a mediator in both peripheral and central sensitization, in part via the prostaglandin E2 receptor-1 (EP-1), and may be a potential target for treating visceral pain. The purpose of this study was to determine whether acid-induced pain hypersensitivity within the non-acid-exposed esophagus (secondary hyperalgesia) is mediated by PGE(2) activation of the EP-1 receptor. METHODS Twelve healthy male subjects participated in a randomized, placebo-controlled crossover study. Upper esophageal pain thresholds (PTs) to electrical stimulation were determined, and either the EP-1 antagonist ZD6416 or a placebo was orally administered. One-hour after dosing, acid or saline (0.15 mol/L) was infused into the lower esophagus for 30 minutes. Upper esophageal PT was monitored for 120 minutes after infusion. RESULTS Except in 1 subject (who was excluded), the pH in the upper esophagus remained above 5 throughout all studies. In 8 subjects, ZD6416 attenuated the reduction in PT in the upper esophagus normally induced by acid infusion into the lower esophagus (area under curve [AUC]: -11.9 +/- 2.5 and 6.4 +/- 6.7 for placebo and ZD6416, respectively; P < 0.01). After saline infusion, the effects of ZD6416 and placebo were similar (AUC: 9.9 +/- 6 and 4.1 +/- 2, respectively; P = 0.8). Three subjects had no reduction in PT to acid infusion with placebo and were excluded at post hoc analysis. CONCLUSIONS The attenuation of secondary esophageal hyperalgesia by ZD6416 suggests that PGE(2), via the EP-1 receptor, contributes to human visceral pain hypersensitivity.
Collapse
Affiliation(s)
- Sanchoy Sarkar
- Department of GI Science, Clinical Sciences Building, University of Manchester, Hope Hospital, Salford M6 8HD, UK
| | | | | | | | | | | | | |
Collapse
|
53
|
Omote K, Yamamoto H, Kawamata T, Nakayama Y, Namiki A. The effects of intrathecal administration of an antagonist for prostaglandin E receptor subtype EP(1) on mechanical and thermal hyperalgesia in a rat model of postoperative pain. Anesth Analg 2002; 95:1708-12, table of contents. [PMID: 12456444 DOI: 10.1097/00000539-200212000-00044] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
UNLABELLED Despite substantial advances in understanding acute pain mechanisms and in the treatment of pain, postoperative pain, especially mechanically evoked pain (incident pain), is generally not effectively treated. Tissue injury and inflammation increase the release of prostaglandin E(2) in the spinal cord, contributing to the development of hyperalgesia. We designed the present study to determine whether the intrathecal administration of an antagonist for prostaglandin E(2) receptor subtype EP(1), ONO-8711, has an analgesic effect on incision-induced mechanical and thermal hyperalgesia. A 1-cm longitudinal skin incision was made in the plantar aspect of the rat foot. The withdrawal threshold to mechanical stimulation and the withdrawal latency to thermal stimulation applied adjacent to the wound of the hindpaw were investigated. Both mechanical and thermal hyperalgesia were observed at 2 h and 24 h after the incision had been made. ONO-8711 (50, 80, 100 micro g) or saline was administered intrathecally. ONO-8711 significantly increased the withdrawal thresholds to mechanical stimulation, but not to thermal stimulation, in a dose- and time-dependent manner. We conclude that EP(1) receptor-mediated sensitization of the spinal dorsal horn may contribute to the generation of mechanical, but not thermal, hyperalgesia and that an EP(1) receptor antagonist administered intrathecally is a potential analgesic for postoperative pain, especially mechanically evoked pain (incident pain). IMPLICATIONS We examined the effects of an intrathecally administered selective EP(1) receptor antagonist on mechanical and thermal hyperalgesia in a postoperative pain model. The intrathecal EP(1) receptor antagonist inhibited the mechanical, but not thermal, hyperalgesia, indicating the potential for an EP(1) receptor antagonist to be used as an analgesic for postoperative pain, especially incident pain.
Collapse
Affiliation(s)
- Keiichi Omote
- Department of Anesthesiology, Sapporo Medical University School of Medicine, Japan.
| | | | | | | | | |
Collapse
|
54
|
Durand S, Fromy B, Bouyé P, Saumet JL, Abraham P. Vasodilatation in response to repeated anodal current application in the human skin relies on aspirin-sensitive mechanisms. J Physiol 2002; 540:261-9. [PMID: 11927685 PMCID: PMC2290218 DOI: 10.1113/jphysiol.2001.013364] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The vasodilatation resulting from prolonged square-wave monopolar current application as used in iontophoresis is assumed to rely on an axon reflex. Involvement of prostaglandins in the anodal current-induced vasodilatation remains unclear. We tested the hypothesis that prostaglandins participate in a sensitisation mechanism to current application rather than as direct vasodilators. In healthy volunteers, laser Doppler flowmetry (LDF) was recorded in the forearm during and following isolated or repeated 0.1 mA transcutaneous anodal current applications, using deionised water as a vehicle. Segmented current applications of 6 or 12 mC resulted in an LDF increase twice that observed following current applications of comparable total charge delivered all at once (P < 0.05). Following a 1 min anodal application, a slow and prolonged LDF drift occurred (slope: 0.3 +/- 0.5 arbitrary units min(-1)). When the same current application was repeated after intervals of 5 and 20 min, an abrupt vasodilatation occurred, with maximal LDF amplitude of 53.5 +/- 34.0 and 48.2 +/- 19.1 arbitrary units, respectively. Pretreatment with 1 g oral aspirin abolished the abrupt vasodilatation to repeated current application but not the initial slow drift. We suggest that vasodilatation occurs through two parallel pathways: (1) a slow progressive drift of LDF of limited amplitude insensitive to aspirin pretreatment, and (2) an abrupt vasodilatation probably resulting from afferent fibre activation, appearing if a preliminary sensitisation by current application is performed. Sensitisation lasts for at least 20 min, and is blocked by aspirin, suggesting participation of prostanoids.
Collapse
Affiliation(s)
- S Durand
- Laboratoire de Physiologie et Explorations Vasculaires, Centre hospitalier universitaire, 49033 Angers cedex, France
| | | | | | | | | |
Collapse
|
55
|
Sorkin LS, Yu AL, Junger H, Doom CM. Antibody directed against GD(2) produces mechanical allodynia, but not thermal hyperalgesia when administered systemically or intrathecally despite its dependence on capsaicin sensitive afferents. Brain Res 2002; 930:67-74. [PMID: 11879797 DOI: 10.1016/s0006-8993(01)03408-4] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Anti-GD(2) antibodies have been shown to be effective for immunotherapy of neuroblastoma and other GD(2) enriched malignancies. Infusion of anti-GD(2) antibodies frequently causes spontaneous pain and allodynia for the duration of the immunotherapy and occasionally longer lasting neuropathic pain. Bolus intravenous injection of anti-GD(2) in rats initiates mechanical allodynia as measured by withdrawal threshold of the hindpaws. In this study, thermal thresholds were measured prior to and for up to 6 h following systemic anti-GD(2) administration in adult rats. In addition, both thermal and mechanical thresholds were tested following intrathecal administration of anti-GD(2) and IgG(2a). Murine anti-GD(2) elicited mechanical allodynia when administered into either the vasculature or the intrathecal space. Effective systemic doses were 1--3 mg/kg as previously shown. Intrathecally, optimal doses ranged from 0.01 to 0.1 ng; a higher dose was ineffective. Thermal hyperalgesia was not observed via either route of administration. Intrathecal pretreatment 48--72 h prior to the experiment with capsaicin at doses sufficient to cause a 50% depletion of dorsal horn CGRP, caused a total blockade of the mechanical allodynia indicating an involvement of peptidergic fine afferent fibers. It is likely that the antibody reacts with an antigen on peripheral nerve and/or myelin to initiate its effect. The lack of observed thermal hyperalgesia is surprising especially in light of the capsaicin-associated blockade, however, it is consistent with several other immune system related models of pain.
Collapse
Affiliation(s)
- L S Sorkin
- Anesthesiology Research Laboratories, University of California-San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0818, USA.
| | | | | | | |
Collapse
|
56
|
Borgland SL, Connor M, Ryan RM, Ball HJ, Christie MJ. Prostaglandin E(2) inhibits calcium current in two sub-populations of acutely isolated mouse trigeminal sensory neurons. J Physiol 2002; 539:433-44. [PMID: 11882676 PMCID: PMC2290145 DOI: 10.1113/jphysiol.2001.013322] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Prostaglandins are important mediators of pain and inflammation. We have examined the effects of prostanoids on voltage-activated calcium currents (I(Ca)) in acutely isolated mouse trigeminal sensory neurons, using standard whole cell voltage clamp techniques. Trigeminal neurons were divided into two populations based on the presence (Type 2) or absence (Type 1) of low voltage-activated T-type I(Ca). The absence of T-type I(Ca) is highly correlated with sensitivity to mu-opioid agonists and the VR1 agonist capsaicin. In both populations of cells, high voltage-activated I(Ca) was inhibited by PGE(2) with an EC(50) of about 35 nM, to a maximum of 30 %. T-type I(Ca) was not inhibited by PGE(2). Pertussis toxin pre-treatment abolished the effects of PGE(2) in Type 2 cells, but not in Type 1 cells, whereas treatment with cholera toxin prevented the effects of PGE(2) in Type 1 cells, but not in Type 2 cells. Inhibition of I(Ca) by PGE(2) was associated with slowing of current activation and could be relieved with a large positive pre-pulse, consistent with inhibition of I(Ca) by G protein betagamma subunits. Reverse transcription-polymerase chain reaction of mRNA from trigeminal ganglia indicated that all four EP prostanoid receptors were present. However, in both Type 1 and Type 2 cells the effects of PGE(2) were only mimicked by the selective EP(3) receptor agonist ONO-AE-248, and not by selective agonists for EP(1) (ONO-DI-004), EP(2) (ONO-AE1-259) and EP(4) (ONO-AE1-329) receptors. These data indicate that two populations of neurons in trigeminal ganglia differing in their calcium channel expression, sensitivity to mu-opioids and capsaicin also have divergent mechanisms of PGE(2)-mediated inhibition of calcium channels, with Gi/Go type G proteins involved in one population, and Gs type G proteins in the other.
Collapse
MESH Headings
- Animals
- Calcium Channel Blockers/pharmacology
- Calcium Channels/drug effects
- Calcium Channels/metabolism
- Calcium Channels, N-Type/drug effects
- Calcium Channels, N-Type/metabolism
- Calcium Channels, Q-Type/drug effects
- Calcium Channels, Q-Type/metabolism
- Cholera Toxin/pharmacology
- Dinoprostone/pharmacology
- Electrophysiology
- Female
- GTP-Binding Protein alpha Subunits, Gi-Go/drug effects
- GTP-Binding Protein alpha Subunits, Gi-Go/metabolism
- GTP-Binding Protein alpha Subunits, Gs/drug effects
- GTP-Binding Protein alpha Subunits, Gs/metabolism
- GTP-Binding Proteins/drug effects
- GTP-Binding Proteins/metabolism
- In Vitro Techniques
- Ion Channel Gating
- Male
- Mice
- Mice, Inbred C57BL
- Neurons, Afferent/drug effects
- Patch-Clamp Techniques
- Pertussis Toxin
- RNA/genetics
- RNA/isolation & purification
- Reverse Transcriptase Polymerase Chain Reaction
- Trigeminal Nerve/drug effects
- Trigeminal Nerve/metabolism
- Virulence Factors, Bordetella/pharmacology
Collapse
|
57
|
Ahmadi S, Lippross S, Neuhuber WL, Zeilhofer HU. PGE(2) selectively blocks inhibitory glycinergic neurotransmission onto rat superficial dorsal horn neurons. Nat Neurosci 2002; 5:34-40. [PMID: 11740501 DOI: 10.1038/nn778] [Citation(s) in RCA: 250] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Despite the crucial role that prostaglandins (PGs) have in the sensitization of the central nervous system to pain, their cellular and molecular targets leading to increased pain perception have remained elusive. Here we investigated the effects of PGE(2) on fast synaptic transmission onto neurons in the rat spinal cord dorsal horn, the first site of synaptic integration in the pain pathway. We identified the inhibitory (strychnine-sensitive) glycine receptor as a specific target of PGE(2). PGE(2), but not PGF(2 alpha), PGD(2) or PGI(2), reduced inhibitory glycinergic synaptic transmission in low nanomolar concentrations, whereas GABAA, AMPA and NMDA receptor-mediated transmission remained unaffected. Inhibition of glycine receptors occurred via a postsynaptic mechanism involving the activation of EP2 receptors, cholera-toxin-sensitive G-proteins and cAMP-dependent protein kinase. Via this mechanism, PGE(2) may facilitate the transmission of nociceptive input through the spinal cord dorsal horn to higher brain areas where pain becomes conscious.
Collapse
Affiliation(s)
- Seifollah Ahmadi
- Institut für Experimentelle und Klinische Pharmakologie und Toxikologie, Emil-Fischer-Zentrum, Fahrstrasse 17, D-91054 Erlangen, Germany
| | | | | | | |
Collapse
|
58
|
Durand S, Fromy B, Bouyé P, Saumet JL, Abraham P. Current-induced vasodilation during water iontophoresis (5 min, 0.10 mA) is delayed from current onset and involves aspirin sensitive mechanisms. J Vasc Res 2002; 39:59-71. [PMID: 11844938 DOI: 10.1159/000048994] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Study of the microcirculation by iontophoresis is potentially confounded by any non-specific effects of current application. Laser Doppler flow (LDF, mean +/- SD; arbitrary units; AU) was recorded on the forearms of healthy volunteers during and 20 min following application of 0.10-mA current for 1, 3 and 5 min, using deionised water as a vehicle. Local heating to 44 degrees C was then applied for 24 min to assess maximal vasodilation. Cathodal current applications resulted in delayed and prolonged vasodilation (peak values: 78 +/- 29, 75 +/- 19, 80 +/- 37 AU) whereas anodal peak LDF was 13 +/- 6, 27 +/- 34 and 72 +/- 40 AU for 1-, 3- and 5-min periods of current applications, respectively. From current onset, inflexion points in the responses to 3- and 5-min anodal current applications occurred at 4.5 and 6.5 min, respectively, and at approximately 1.5 min for all cathodal current applications. For 5-min current applications: a preliminary tourniquet ischaemia neither changed the time course nor the amplitude of the response to current application. In this situation, local anaesthesia abolished the current-induced vasodilation. Chronic capsaicin pretreatment decreased the amplitude of the vasodilation. Pretreatment with 500 mg oral aspirin decreased the cathodal vasodilation and abolished the anodal vasodilation, even in the absence of preliminary ischaemia. We conclude that vasodilation to prolonged application of 0.10-mA continuous monopolar current after transient tourniquet ischaemia cannot be exclusively the result of an axon reflex initiated by current onset. This current-induced vasodilation is at least partly dependent on capsaicin-sensitive afferent fibres and relies on aspirin-sensitive mechanisms at both polarities.
Collapse
Affiliation(s)
- S Durand
- Laboratory of Physiology, University Hospital, Angers, France
| | | | | | | | | |
Collapse
|
59
|
Spinal prostaglandins are involved in the development but not the maintenance of inflammation-induced spinal hyperexcitability. J Neurosci 2001. [PMID: 11698610 DOI: 10.1523/jneurosci.21-22-09001.2001] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Prostaglandins (PGs) are local mediators of several functions in the CNS. Both primary afferent neurons and intrinsic cells in the spinal cord produce PGs, with a marked upregulation during peripheral inflammation. Therefore, the significance of spinal PGs in the neuronal processing of mechanosensory information was herein investigated. In anesthetized rats, the discharges of spinal nociceptive neurons with input from the knee joint were extracellularly recorded. Topical administration of prostaglandin E(2) (PGE(2)) to the spinal cord facilitated the discharges and expanded the receptive field of dorsal horn neurons to innocuous and noxious pressure applied to the knee joint, the ankle, and the paw, thus mimicking inflammation-induced central sensitization. Conversely, topical administration of the PG synthesis inhibitor indomethacin to the spinal cord before and during development of knee joint inflammation attenuated the generation of inflammation-induced spinal neuronal hyperexcitability. However, after development of inflammation, the responses of spinal neurons to mechanical stimuli were only reduced by systemic indomethacin but not by indomethacin applied to the spinal cord. Thus, spinal PG synthesis is important for the induction and initial expression but not for the maintenance of spinal cord hyperexcitability. Spinal PGE(2) application facilitated dorsal horn neuronal firing elicited by ionophoretic delivery of NMDA, suggesting that an interaction of PGs and NMDA receptors may contribute to inflammation-induced central sensitization. However, after development of inflammation, spinal indomethacin failed to reduce responses to ionophoretic delivery of NMDA or AMPA, suggesting that such an interaction is not required for the maintenance of central sensitization.
Collapse
|
60
|
Ito S, Okuda-Ashitaka E, Minami T. Central and peripheral roles of prostaglandins in pain and their interactions with novel neuropeptides nociceptin and nocistatin. Neurosci Res 2001; 41:299-332. [PMID: 11755218 DOI: 10.1016/s0168-0102(01)00289-9] [Citation(s) in RCA: 136] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
While acute pain has a fundamental role to operate a protective system, chronic pain associated with inflammation and nerve injury often outlasts its biological usefulness. Therefore, there has recently been great interest in the neurochemical mechanisms of hyperalgesia to noxious stimuli and tactile pain (allodynia) to innocuous stimuli with a hope to relieve persistent, intractable pain. Over several decades non-steroidal anti-inflammatory drugs and opioids have been employed for clinical management of pain. The introduction of molecular biology to pain research has enabled us to describe the mechanism of pain at the molecular level and to develop analgesics with selectivity for targets and with less adverse effects. This review focuses on current knowledge concerning mechanisms and pathways for pain induced by prostaglandins and their interactions with novel neuropeptides nociceptin/orphanin FQ and nocistatin derived from the same opioid precursor protein.
Collapse
Affiliation(s)
- S Ito
- Department of Medical Chemistry, Kansai Medical University, 10-15 Fumizono, Moriguchi 570-8506, Japan.
| | | | | |
Collapse
|
61
|
Tegeder I, Niederberger E, Vetter G, Bräutigam L, Geisslinger G. Effects of selective COX-1 and -2 inhibition on formalin-evoked nociceptive behaviour and prostaglandin E(2) release in the spinal cord. J Neurochem 2001; 79:777-86. [PMID: 11723170 DOI: 10.1046/j.1471-4159.2001.00613.x] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Nociception evoked prostaglandin (PG) release in the spinal cord considerably contributes to the induction of hyperalgesia and allodynia. To evaluate the relative contribution of cyclooxygenase-1 (COX-1) and COX-2 in this process we assessed the effects of the selective COX-1 inhibitor SC560 and the selective COX-2 inhibitor celecoxib on formalin-evoked nociceptive behaviour and spinal PGE(2) release. SC560 (10 and 20 mg/kg) significantly reduced the nociceptive response and completely abolished the formalin-evoked PGE(2) raise. In contrast, celecoxib (10 and 20 mg/kg) was ineffective in both regards, i.e. the flinching behaviour was largely unaltered and the formalin-induced PGE(2) raise as assessed using microdialysis was only slightly, not significantly reduced. This suggests that the formalin-evoked rapid PG release was primarily caused by COX-1 and was independent of COX-2. Mean free spinal cord concentrations of celecoxib during the formalin assay were 32.0 +/- 4.5 nM, thus considerably higher than the reported IC50 for COX-2 (3-7 nM). Therefore, the lack of efficacy of celecoxib is most likely not to be a result of poor tissue distribution. COX-2 mRNA and protein expression in the spinal cord were not affected by microdialysis alone but the mRNA rapidly increased following formalin injection and reached a maximum at 2 h. COX-2 protein was unaltered up to 4 h after formalin injection. The time course of COX-2 up-regulation suggests that the formalin-induced nociceptive response precedes COX-2 protein de novo synthesis and may therefore be unresponsive to COX-2 inhibition. Considering the results obtained with the formalin model it may be hypothesized that the efficacy of celecoxib in early injury evoked pain may be less than that of unselective NSAIDs.
Collapse
Affiliation(s)
- I Tegeder
- pharmazentrum frankfurt, Klinikum der Johann Wolfgang Goethe-Universität, Frankfurt am Main, Germany
| | | | | | | | | |
Collapse
|
62
|
Uchino S, Watanabe W, Nakamura T, Shuto S, Kazuta Y, Matsuda A, Nakajima-Iijima S, Kudo Y, Kohsaka S, Mishina M. Establishment of CHO cell lines expressing four N-methyl-D-aspartate receptor subtypes and characterization of a novel antagonist PPDC. FEBS Lett 2001; 506:117-22. [PMID: 11591383 DOI: 10.1016/s0014-5793(01)02899-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
To develop an assay system that allows the N-methyl-D-aspartate (NMDA) receptor subtype-selective antagonistic potency of drugs, we have established Chinese hamster ovary cell lines expressing the four NMDA receptor subtypes (GluRepsilon1/zeta1-GluRepsilon4/zeta1) heat-indelibly. Using these clonal cells, we found that a novel antagonist, (1S,2R)-1-phenyl-2[(S)-1-aminopropyl]-N,N-diethylcyclopropanecarboxamide, was less selective for the GluRepsilon1/zeta1: the IC(50) values for the GluRepsilon1/zeta1-GluRepsilon4/zeta1 were 41.7, 13.3, 12.6 and 11.5 microM, respectively, while two well-known antagonists, DL-2-amino-5-phosphonovaleric acid and ifenprodil, showed the known potency and selectivity for each subtype. Thus, the established clonal cells are of use in characterizing the pharmacological properties of drugs that act on NMDA receptors.
Collapse
Affiliation(s)
- S Uchino
- Department of Neurochemistry, National Institute of Neuroscience, Kodaira, Tokyo, Japan.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
63
|
Minami T, Nakano H, Kobayashi T, Sugimoto Y, Ushikubi F, Ichikawa A, Narumiya S, Ito S. Characterization of EP receptor subtypes responsible for prostaglandin E2-induced pain responses by use of EP1 and EP3 receptor knockout mice. Br J Pharmacol 2001; 133:438-44. [PMID: 11375261 PMCID: PMC1572799 DOI: 10.1038/sj.bjp.0704092] [Citation(s) in RCA: 136] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Prostaglandin E2 (PGE2) is known to be the principal pro-inflammatory prostanoid and play an important role in nociception. To identify PGE receptor (EP) subtypes that mediate pain responses to noxious and innocuous stimuli, we studied them by use of EP1 and EP3 knockout (EP1(-/-) and EP3(-/-)) mice. PGE2 could induce mechanical allodynia in EP1(+/+), EP3(+/+) and EP3(-/-) mice, but not in EP1(-/-) mice. N-methyl-D-aspartate (NMDA), the substrate of nitric oxide (NO) synthase L-arginine, or the NO donor sodium nitroprusside administered intrathecal (i.t.) could induce allodynia in EP3(-/-) and EP1(-/-) mice. Activation of EP1 receptors appears to be upstream, rather than downstream, of NMDA receptor activation and NO production in the PGE2-induced allodynia. Although PGE2 produced thermal hyperalgesia over a wide range of dosages from 50 pg to 0.5 microg kg(-1) in EP3(+/+) mice, it showed a monophasic hyperalgesic action at 5 ng kg(-1) or higher doses in EP3(-/-) mice. The selective EP3 agonist, ONO-AE-248, induced hyperalgesia at 500 pg kg(-1) in EP3(+/+) mice, but not in EP3(-/-) mice. Saline-injected EP1(-/-) mice showed hyperalgesia, which was reversed by i.t. PGE2 in a dose-dependent manner. There was no significant difference in the formalin-induced behaviours between EP1(-/-) or EP3(-/-) mice and the cognate wild-type mice. These results demonstrate that spinal EP1 receptors are involved in the PGE2-induced allodynia and that spinal EP3 receptors are involved in the hyperalgesia induced by low doses of PGE2. However, the formalin-induced pain cannot be ascribed to a single EP receptor subtype EP1 or EP3.
Collapse
Affiliation(s)
- Toshiaki Minami
- Department of Anesthesiology, Osaka Medical College, Takatsuki 569-8686, Japan
| | - Hiroyuki Nakano
- Department of Anesthesiology, Osaka Medical College, Takatsuki 569-8686, Japan
| | - Takuya Kobayashi
- Department of Pharmacology, Faculty of Medicine, Kyoto University, Kyoto 606-8315, Japan
| | - Yukihiko Sugimoto
- Department of Physiological Chemistry, Faculty of Pharmaceutical Sciences, Kyoto University, Kyoto 606-8315, Japan
| | - Fumitaka Ushikubi
- Department of Pharmacology, Asahikawa Medical College, Asahikawa 078-8510, Japan
| | - Atsushi Ichikawa
- Department of Physiological Chemistry, Faculty of Pharmaceutical Sciences, Kyoto University, Kyoto 606-8315, Japan
| | - Shuh Narumiya
- Department of Pharmacology, Faculty of Medicine, Kyoto University, Kyoto 606-8315, Japan
| | - Seiji Ito
- Department of Medical Chemistry, Kansai Medical University, Moriguchi 570-8506, Japan
- Author for correspondence:
| |
Collapse
|
64
|
Minami T, Bakoshi S, Nakano H, Mine O, Muratani T, Mori H, Ito S. The Effects of Capsaicin Cream on Prostaglandin-Induced Allodynia. Anesth Analg 2001. [DOI: 10.1213/00000539-200108000-00037] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
|
65
|
Minami T, Bakoshi S, Nakano H, Mine O, Muratani T, Mori H, Ito S. The effects of capsaicin cream on prostaglandin-induced allodynia. Anesth Analg 2001; 93:419-23, 4th contents page. [PMID: 11473873 DOI: 10.1097/00000539-200108000-00037] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
UNLABELLED Although intradermal injection of capsaicin produces acute pain and secondary hyperalgesia, long-term topical application of capsaicin cream has been used as a medication for pain relief in various pain conditions. We previously reported that intrathecal administration of prostaglandin (PG) E(2) and PGF(2alpha) into mice induced touch-evoked pain (allodynia) through capsaicin-sensitive and capsaicin-insensitive afferent fibers, respectively. To clarify the mechanism of an analgesic effect by capsaicin cream, here we applied it to the tail and hind paws of mice and investigated its effects on PGE(2)- and PGF(2alpha)-induced allodynia. Twenty-four-hour pretreatment of mice with 0.025% or 0.05% capsaicin cream markedly alleviated allodynia induced by PGE(2), but not by PGF(2alpha). These results suggest that the topical application of capsaicin cream modulates capsaicin-sensitive afferents and ameliorates allodynia evoked by PGE(2) at the spinal level. IMPLICATIONS Topical application of capsaicin cream alleviates touch-evoked pain induced by the intrathecal administration of prostaglandin E(2). This study may provide a rationale for the use of capsaicin cream as a therapeutic drug for pain relief.
Collapse
Affiliation(s)
- T Minami
- Department of Anesthesiology, Osaka Medical College, Takatsuki, Japan
| | | | | | | | | | | | | |
Collapse
|
66
|
Vanegas H, Schaible HG. Prostaglandins and cyclooxygenases [correction of cycloxygenases] in the spinal cord. Prog Neurobiol 2001; 64:327-63. [PMID: 11275357 DOI: 10.1016/s0301-0082(00)00063-0] [Citation(s) in RCA: 286] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The spinal cord is one of the sites where non-steroidal anti-inflammatory drugs (NSAIDs) act to produce analgesia and antinociception. Expression of cyclooxygenase(COX)-1 and COX-2 in the spinal cord and primary afferents suggests that NSAIDs act here by inhibiting the synthesis of prostaglandins (PGs). Basal release of PGD(2), PGE(2), PGF(2alpha) and PGI(2) occurs in the spinal cord and dorsal root ganglia. Prostaglandins then bind to G-protein-coupled receptors located in intrinsic spinal neurons (receptor types DP and EP2) and primary afferent neurons (EP1, EP3, EP4 and IP). Acute and chronic peripheral inflammation, interleukins and spinal cord injury increase the expression of COX-2 and release of PGE(2) and PGI(2). By activating the cAMP and protein kinase A pathway, PGs enhance tetrodotoxin-resistant sodium currents, inhibit voltage-dependent potassium currents and increase voltage-dependent calcium inflow in nociceptive afferents. This decreases firing threshold, increases firing rate and induces release of excitatory amino acids, substance P, calcitonin gene-related peptide (CGRP) and nitric oxide. Conversely, glutamate, substance P and CGRP increase PG release. Prostaglandins also facilitate membrane currents and release of substance P and CGRP induced by low pH, bradykinin and capsaicin. All this should enhance elicitation and synaptic transfer of pain signals in the spinal cord. Direct administration of PGs to the spinal cord causes hyperalgesia and allodynia, and some studies have shown an association between induction of COX-2, increased PG release and enhanced nociception. NSAIDs diminish both basal and enhanced PG release in the spinal cord. Correspondingly, spinal application of NSAIDs generally diminishes neuronal and behavioral responses to acute nociceptive stimulation, and always attenuates behavioral responses to persistent nociception. Spinal application of specific COX-2 inhibitors sometimes diminishes behavioral responses to persistent nociception.
Collapse
Affiliation(s)
- H Vanegas
- Instituto Venezolano de Investigaciones Científicas (IVIC), Apartado 21827, 1020A, Caracas, Venezuela.
| | | |
Collapse
|
67
|
Minami T, Matsumura S, Okuda-Ashitaka E, Shimamoto K, Sakimura K, Mishina M, Mori H, Ito S. Characterization of the glutamatergic system for induction and maintenance of allodynia. Brain Res 2001; 895:178-85. [PMID: 11259776 DOI: 10.1016/s0006-8993(01)02069-8] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Glutamate is the main excitatory neurotransmitter in the central nervous system and has been shown to be involved in spinal nociceptive processing. We previously demonstrated that intrathecal (i.t.) administration of prostaglandin (PG) E(2) and PGF(2 alpha) induced touch-evoked pain (allodynia) through the glutamatergic system by different mechanisms. In the present study, we characterized glutamate receptor subtypes and glutamate transporters involved in induction and maintenance of PGE(2)- and PGF(2 alpha)-evoked allodynia. In addition to PGE(2) and PGF(2 alpha), N-methyl-D-aspartate (NMDA) and alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA), but not kainate, induced allodynia. PGE(2)- and NMDA-induced allodynia were observed in NMDA receptor epsilon 4 (NR2D) subunit knockout (GluR epsilon 4(-/-)) mice, but not in epsilon 1 (NR2A) subunit knockout (GluR epsilon 1(-/-)) mice. Conversely, PGF(2 alpha)- and AMPA-induced allodynia were observed in GluR epsilon 1(-/-) mice, but not in GluR epsilon 4(-/-) mice. The induction of allodynia by PGE(2) and NMDA was abolished by the NMDA receptor epsilon 2 (NR2B) antagonist CP-101,606 and neonatal capsaicin treatment. PGF(2 alpha)- and AMPA-induced allodynia were not affected by CP-101,606 and by neonatal capsaicin treatment. On the other hand, the glutamate transporter blocker DL-threo-beta-benzyloxyaspartate (DL-TBOA) blocked all the allodynia induced by PGE(2), PGF(2 alpha), NMDA, and AMPA. These results demonstrate that there are two pathways for induction of allodynia mediated by the glutamatergic system and suggest that the glutamate transporter is essential for the induction and maintenance of allodynia.
Collapse
Affiliation(s)
- T Minami
- Department of Anesthesiology, Osaka Medical College, Takatsuki 569-8686, Japan
| | | | | | | | | | | | | | | |
Collapse
|
68
|
Moore KA, Baba H, Woolf CJ. Synaptic transmission and plasticity in the superficial dorsal horn. PROGRESS IN BRAIN RESEARCH 2001; 129:63-80. [PMID: 11098682 DOI: 10.1016/s0079-6123(00)29006-7] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- K A Moore
- Department of Anesthesia and Critical Care, Massachusetts General Hospital, Charleston 02129-2000, USA.
| | | | | |
Collapse
|
69
|
Central anatomy of individual rapidly adapting low-threshold mechanoreceptors innervating the ?hairy? skin of newborn mice: Early maturation of hair follicle afferents. J Comp Neurol 2001. [DOI: 10.1002/cne.1069] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
70
|
The Effect of Spinal Ibuprofen on Opioid Withdrawal in the Rat. Anesth Analg 2000. [DOI: 10.1213/00000539-200008000-00035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
|
71
|
Eaton MJ. Emerging cell and molecular strategies for the study and treatment of painful peripheral neuropathies. J Peripher Nerv Syst 2000; 5:59-74. [PMID: 10905465 DOI: 10.1046/j.1529-8027.2000.00006.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Pharmacologic treatment for the symptoms of painful neuropathy has been problematic, because there has been limited understanding of the underlying etiologies and systemic levels that an effective dose can have on multiple side effects. The use of molecular methods, such as gene deletion from knockout mice and cellular minipumps for delivery of biologic antinociceptive molecules, has led to a better understanding of the underlying mechanisms of the induction of intractable neuropathic pain. The initiation of an excitatory cascade after injury or disease leads to the induction of various second messenger systems, loss or down-regulation of the endogenous inhibitory spinal GABA system and central sensitization, causing such pain. The development and use of cellular minipumps, immortalized cell lines bioengineered to secrete various antinociceptive molecules for the reversal of neuropathic pain, makes cellular therapy a strategy for clinical use in the next few years. The development of molecular "disimmortalization" technologies will make the use of such engineered cell lines safe for human use. Direct somatic gene transfer for neuropathic pain will eventually overcome the problems associated with transplantation of non-autologous and xenogenic cells. These virus-mediated methods, although at the early stages of evolution and use, offer large-scale production of biologic agents that can be conveniently and confidently used for the long-term relief of chronic neuropathic pain in a clinical setting, without systemic effects or surgical interventions.
Collapse
Affiliation(s)
- M J Eaton
- The Miami Project to Cure Paralysis and the Department of Neurological Surgery, University of Miami School of Medicine, Florida 33136, USA.
| |
Collapse
|