1
|
Yuan S, Wang N, Yao Y, Liu J, Gao M, Mo H, Zhang S, Su R. Role of 5-HT 2A receptor in modulating glutamatergic activity in the ventrolateral orbital cortex: implication in trigeminal neuralgia. Neuroscience 2022; 502:107-116. [PMID: 36038038 DOI: 10.1016/j.neuroscience.2022.08.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Revised: 08/02/2022] [Accepted: 08/23/2022] [Indexed: 11/16/2022]
Abstract
5-HT2A receptors (5-HT2ARs) are widely expressed in the central nervous system, including in the ventrolateral orbital cortex (VLO). The VLO is an important cortical component for pain processing. Brain 5-HT2ARs are implicated in both pro- and anti- nociceptive functions. However, the roles of 5-HT2ARs in the VLO in trigeminal neuralgia and neuronal synaptic function remain to be understood. We used chronic constriction injury of infraorbital nerve (IoN-CCI) model and shRNA mediated gene knockdown in mice to investigate the role of 5-HT2ARs in the VLO in trigeminal neuralgia. We found that knockdown of 5-HT2ARs in the VLO aggravated spontaneous pain and mechanical allodynia in mice after IoN-CCI. At the synaptic level, decreasing 5-HT2AR expression by shRNA or inhibition of 5-HT2AR activity by its antagonist ketanserin decreased the frequency and amplitude of spontaneous excitatory postsynaptic currents (sEPSCs) of the neurons in the VLO, whereas 5-HT2AR partial agonist 2,5-Dimethoxy-4-iodoamphetamine (DOI) enhanced sEPSCs of the neurons in the VLO. In summary, 5-HT2ARs in the VLO modulate the trigeminal pain by regulating neuronal glutamatergic activity.
Collapse
Affiliation(s)
- Shanshan Yuan
- Beijing Institute of Pharmacology and Toxicology, Beijing, China; School of Stomatology, Jiamusi University, Jiamusi, China
| | - Na Wang
- Beijing Institute of Pharmacology and Toxicology, Beijing, China
| | - Yunxia Yao
- Beijing Institute of Pharmacology and Toxicology, Beijing, China
| | - Junhong Liu
- Beijing Institute of Pharmacology and Toxicology, Beijing, China
| | - Mingwei Gao
- Beijing Institute of Pharmacology and Toxicology, Beijing, China
| | - Hongbing Mo
- School of Stomatology, Jiamusi University, Jiamusi, China
| | - Shuzhuo Zhang
- Beijing Institute of Pharmacology and Toxicology, Beijing, China.
| | - Ruibin Su
- Beijing Institute of Pharmacology and Toxicology, Beijing, China
| |
Collapse
|
2
|
Yuan XC, Wang YY, Tian LX, Yan XJ, Guo YX, Zhao YL, Baba SS, Jia H, Wang HS, Li M, Huo FQ. Spinal 5-HT2A Receptor is Involved in Electroacupuncture Inhibition of Chronic Pain. Mol Pain 2022; 18:17448069221087583. [PMID: 35240891 PMCID: PMC9006364 DOI: 10.1177/17448069221087583] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Knee osteoarthritis (KOA) is a highly prevalent, chronic joint disorder, and it is a typical disease which can develop chronic pain. Our previous study has proved that endocannabinoid (2-AG)-CB1R-GABA-5-HT pathway is involved in electroacupuncture (EA) mediated inhibition of chronic pain. However, it is still unclear which among the 5-HT receptor subtype is involved in EA evoked 5-HT mediated inhibition of chronic pain in the dorsal spinal cord. 5-HT2A is a G protein-coupled receptor and it is involved in 5-HT descending pain modulation system. We found that EA treatment at frequency of 2 Hz +1 mA significantly increased the expression of 5-HT2A receptor in the dorsal spinal cord and intrathecal injection of 5-HT2A receptor antagonist or agonist reversed or mimicked the analgesic effect of EA in each case respectively. Intrathecal injection of a selective GABAA receptor antagonist Bicuculline also reversed the EA effect on pain hypersensitivity. Additionally, EA treatment reversed the reduced expression of GABAA receptor and KCC2 in the dorsal spinal cord of KOA mice. Furthermore, we demonstrated that intrathecal 5-HT2A receptor antagonist/agonist reversed or mimicked the effect of EA up-regulate of KCC2 expression, respectively. Similarly, intrathecal injection of PLC and PKC inhibitors prevented both anti-allodynic effect and up-regulation of KCC2 expression by EA treatment. Our data suggest that EA treatment up-regulated KCC2 expression through activating 5-HT2A-Gq-PLC-PKC pathway and enhanced the inhibitory function of GABAA receptor, thereby inhibiting chronic pain in a mouse model of KOA.
Collapse
Affiliation(s)
| | | | - Li-Xia Tian
- Department of Physiology and Pathophysiology
| | | | - Yi-Xiao Guo
- Department of Physiology and Pathophysiology
| | | | | | | | | | - Man Li
- Department of Neurobiology
| | - Fu-Quan Huo
- Department of Physiology and Pathophysiology
| |
Collapse
|
3
|
Shimizu S, Nakatani Y, Kurose M, Imbe H, Ikeda N, Takagi R, Yamamura K, Okamoto K. Modulatory effects of repeated psychophysical stress on masseter muscle nociception in the nucleus raphe magnus of rats. J Oral Sci 2020; 62:231-235. [PMID: 32074544 DOI: 10.2334/josnusd.19-0320] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
Abstract
Psychophysical stress can cause neural changes that increase nociception in the orofacial region, particularly the masseter muscle (MM). The nucleus raphe magnus (NRM), which is located in the brain stem, serves the crucial role of regulating nociception through descending modulatory pain control. However, it remains unclear if neural activities in the NRM are affected under psychophysical stress conditions. This study conducted experiments to assess (1) whether neural activity, indicated by Fos expression in an NRM that has experienced MM injury, is affected by the stress of repeated forced swim tests (FST); and (2) whether the selective serotonin reuptake inhibitor fluoxetine administered daily after an FST could affect the number of Fos-positive neurons in the NRM. Results revealed that the stress from repeated FSTs significantly increased the number of Fos-positive neurons in an NRM that had been affected by MM injury. Fluoxetine inhibited increases in the number of Fos-positive neurons in the NRM that occurred as a result of FSTs, but this was not observed in sham rats. These findings indicate that the stress from FSTs could increase nociceptive neural activity in an NRM that has experienced MM injury. This could be due, in part, to changes in serotonergic mechanisms.
Collapse
Affiliation(s)
- Shiho Shimizu
- Division of Oral Physiology, Niigata University Graduate School of Medical and Dental Sciences.,Division of Oral and Maxillofacial Surgery, Niigata University Graduate School of Medical and Dental Sciences
| | - Yosuke Nakatani
- Division of Oral Physiology, Niigata University Graduate School of Medical and Dental Sciences.,Division of Oral and Maxillofacial Surgery, Niigata University Graduate School of Medical and Dental Sciences
| | - Masayuki Kurose
- Division of Oral Physiology, Niigata University Graduate School of Medical and Dental Sciences
| | - Hiroki Imbe
- Department of Physiology, Wakayama Medical University
| | - Nobuyuki Ikeda
- Division of Oral and Maxillofacial Surgery, Niigata University Graduate School of Medical and Dental Sciences
| | - Ritsuo Takagi
- Division of Oral and Maxillofacial Surgery, Niigata University Graduate School of Medical and Dental Sciences
| | - Kensuke Yamamura
- Division of Oral Physiology, Niigata University Graduate School of Medical and Dental Sciences
| | - Keiichiro Okamoto
- Division of Oral Physiology, Niigata University Graduate School of Medical and Dental Sciences
| |
Collapse
|
4
|
Di Giovanni G, Chagraoui A, Bharatiya R, De Deurwaerdère P. Serotonergic control of excitability: from neuron to networks. HANDBOOK OF BEHAVIORAL NEUROSCIENCE 2020. [DOI: 10.1016/b978-0-444-64125-0.00010-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
|
5
|
Dong R, Yu B, Chen L, Yu W. The 5-HT 2A receptor potassium-chloride cotransporter 2 signaling pathway in a rat incision pain model. Exp Ther Med 2016; 12:3583-3588. [PMID: 28101155 PMCID: PMC5228180 DOI: 10.3892/etm.2016.3807] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Accepted: 10/03/2016] [Indexed: 12/26/2022] Open
Abstract
Postoperative pain is a critical problem in clinical pain administration. Due to the unclear formation mechanism of postoperative pain, the treatment of postoperative pain is still in the symptomatic treatment stage and lacking satisfactory analgesic effect. Postoperative pain can be simulated by using a rat incision pain model. We observed changes in pain-related behavior of rats affected by the 5-hydroxytryptamine 2A receptor (5-HT2AR) agonist, TCB-2, and antagonist, ketanserin, through intrathecal delivery. The transcription and translation level of potassium-chloride cotransporter 2 (KCC2) in the spinal cord was also measured to investigate the role of the 5-HT2AR-KCC2 pathway in the mechanism of incision pain. Compared with the control group, rats in the incision pain group had decreased mechanical withdrawal threshold (MWT), with significant differences on day 1–7 after surgery, and significant decreases in thermal withdrawal latency (TWL) on days 1, 2, 3 and 6 (P<0.05). Compared with the incision + dimethyl sulfoxide (DMSO) group, MWT and TWL decreased in the incision + ketanserin group on day 1 and 2 (P<0.05). There was no significant difference detected in TWL of incision + TCB-2 group on day 1, while MWT increased significantly compared to the incision + DMSO group (P<0.05). Furthermore, the transcription and translation levels of KCC2 in the incision + ketanserin group decreased significantly in comparison to the incision + DMSO group (P<0.05), while an increase was detected in the incision + TCB-2 group (P<0.05). MWT and TWL decreased in the incision pain rats, accompanied with a decreased transcription and translation level of KCC2. Intrathecal delivery of the 5-HT2AR agonist, TCB-2, alleviated the decreased WMT and inhibited the decreased transcription and translation level of KCC2, while intrathecal delivery of the 5-HT2AR antagonist, ketanserin, aggravated the decreased WMT and transcription and translation levels of KCC2, suggesting the involement of the 5-HT2AR-KCC2 pathway in the formation mechanism of incision pain in rats.
Collapse
Affiliation(s)
- Rong Dong
- Department of Anesthesiology, Eastern Hepatobiliary Hospital, The Second Military Medical University, Shanghai 200438, P.R. China; Department of Anesthesiology, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200025, P.R. China
| | - Buwei Yu
- Department of Anesthesiology, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200025, P.R. China
| | - Lijiao Chen
- Department of Anesthesiology, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200025, P.R. China
| | - Weifeng Yu
- Department of Anesthesiology, Eastern Hepatobiliary Hospital, The Second Military Medical University, Shanghai 200438, P.R. China
| |
Collapse
|
6
|
5-Hydroxytryptamine 2A/2C receptors of nucleus raphe magnus and gigantocellularis/paragigantocellularis pars α reticular nuclei modulate the unconditioned fear-induced antinociception evoked by electrical stimulation of deep layers of the superior colliculus and dorsal periaqueductal grey matter. Behav Brain Res 2016; 316:294-304. [PMID: 27616344 DOI: 10.1016/j.bbr.2016.09.016] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Revised: 08/29/2016] [Accepted: 09/06/2016] [Indexed: 11/21/2022]
Abstract
The electrical stimulation of the dorsolateral columns of the periaquedutal grey matter (dlPAG) or deep layers of the superior colliculus (dlSC) evokes defensive behaviours followed by an antinociceptive response. Monoaminergic brainstem reticular nuclei are suggested to comprise the endogenous pain modulatory system. The aim of the present work was to investigate the role played by 5-HT2 subfamily of serotonergic receptors of the nucleus raphe magnus (NRM) and the gigantocellularis/paragigantocellularis pars α reticular nuclei (Gi/PGiα) in the elaboration of instinctive fear-induced antinociception elicited by electrical stimulation of dlPAG or of dlSC. The nociceptive thresholds were measured by the tail-flick test in Wistar rats. The 5-HT2A/2C-serotonergic receptors antagonist ritanserin was microinjected at different concentrations (0.05, 0.5 and 5.0μg/0.2μL) either in Gi/PGiα or in NRM. The blockade of 5-HT2 receptors in both Gi/PGiα and NRM decreased the innate fear-induced antinociception elicited by electrical stimulation of the dlSC or the dlPAG. These findings indicate that serotonin is involved in the hypo-algesia induced by unconditioned fear-induced behavioural responses and the 5-HT2A/2C-serotonergic receptor subfamily in neurons situated in the Gi/PGiα complex and NRM are critically recruited in pain modulation during the panic-like emotional behaviour.
Collapse
|
7
|
Guiard BP, Di Giovanni G. Central serotonin-2A (5-HT2A) receptor dysfunction in depression and epilepsy: the missing link? Front Pharmacol 2015; 6:46. [PMID: 25852551 PMCID: PMC4362472 DOI: 10.3389/fphar.2015.00046] [Citation(s) in RCA: 82] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2015] [Accepted: 02/24/2015] [Indexed: 11/17/2022] Open
Abstract
5-Hydroxytryptamine 2A receptors (5-HT2A-Rs) are G-protein coupled receptors. In agreement with their location in the brain, they have been implicated not only in various central physiological functions including memory, sleep, nociception, eating and reward behaviors, but also in many neuropsychiatric disorders. Interestingly, a bidirectional link between depression and epilepsy is suspected since patients with depression and especially suicide attempters have an increased seizure risk, while a significant percentage of epileptic patients suffer from depression. Such epidemiological data led us to hypothesize that both pathologies may share common anatomical and neurobiological alteration of the 5-HT2A signaling. After a brief presentation of the pharmacological properties of the 5-HT2A-Rs, this review illustrates how these receptors may directly or indirectly control neuronal excitability in most networks involved in depression and epilepsy through interactions with the monoaminergic, GABAergic and glutamatergic neurotransmissions. It also synthetizes the preclinical and clinical evidence demonstrating the role of these receptors in antidepressant and antiepileptic responses.
Collapse
Affiliation(s)
- Bruno P Guiard
- CNRS, Centre de Recherches sur la Cognition Animale, UMR 5169, Toulouse France ; CNRS, Centre de Recherches sur la Cognition Animale Université de Toulouse 3, UMR 5169, Toulouse, France ; INSERM U1178 Team ≪Depression and Antidepressants≫ Faculté de Pharmacie Paris Sud, Châtenay-Malabry, France
| | - Giuseppe Di Giovanni
- Neurophysiology Unit, Laboratory for the Study of Neurological Disorders, Department of Physiology and Biochemistry, University of Malta, Msida Malta ; School of Biosciences, University of Cardiff, Cardiff UK
| |
Collapse
|
8
|
Walsh DA, McWilliams DF. Mechanisms, impact and management of pain in rheumatoid arthritis. Nat Rev Rheumatol 2014; 10:581-92. [PMID: 24861185 DOI: 10.1038/nrrheum.2014.64] [Citation(s) in RCA: 177] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
People with rheumatoid arthritis (RA) identify pain as their most important symptom, one that often persists despite optimal control of inflammatory disease. RA pain arises from multiple mechanisms, involving inflammation, peripheral and central pain processing and, with disease progression, structural change within the joint. Consequently, RA pain has a wide range of characteristics-constant or intermittent, localized or widespread-and is often associated with psychological distress and fatigue. Dominant pain mechanisms in an individual are identified by critical evaluation of clinical symptoms and signs, and by laboratory and imaging tests. Understanding these mechanisms is essential for effective management, although evidence from preclinical models should be interpreted with caution. A range of pharmacological analgesic and immunomodulatory agents, psychological interventions and surgery may help manage RA pain. Pain contributes importantly to the clinical assessment of inflammatory disease activity, and noninflammatory components of RA pain should be considered when gauging eligibility for or response to biologic agents. Further randomized controlled trials are required to determine the optimal usage of analgesics in RA, and novel agents with greater efficacy and lower propensity for adverse events are urgently needed. Meanwhile, targeted use of existing treatments could reduce pain in people with RA.
Collapse
Affiliation(s)
- David A Walsh
- Arthritis Research UK Pain Centre, Academic Rheumatology, University of Nottingham, Clinical Sciences Building, City Hospital, Hucknall Road, Nottingham NG5 1PB, UK
| | - Daniel F McWilliams
- Arthritis Research UK Pain Centre, Academic Rheumatology, University of Nottingham, Clinical Sciences Building, City Hospital, Hucknall Road, Nottingham NG5 1PB, UK
| |
Collapse
|
9
|
Mehalick ML, Ingram SL, Aicher SA, Morgan MM. Chronic inflammatory pain prevents tolerance to the antinociceptive effect of morphine microinjected into the ventrolateral periaqueductal gray of the rat. THE JOURNAL OF PAIN 2013; 14:1601-10. [PMID: 24161274 DOI: 10.1016/j.jpain.2013.08.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2013] [Revised: 07/12/2013] [Accepted: 08/03/2013] [Indexed: 01/15/2023]
Abstract
UNLABELLED The ventrolateral periaqueductal gray (vlPAG) contributes to morphine antinociception and tolerance. Chronic inflammatory pain causes changes within the PAG that are expected to enhance morphine tolerance. This hypothesis was tested by assessing antinociception and tolerance following repeated microinjections of morphine into the vlPAG of rats with chronic inflammatory pain. Microinjection of morphine into the vlPAG reversed the allodynia caused by intraplantar administration of complete Freund's adjuvant and produced antinociception on the hot plate test. Although there was a gradual decrease in morphine antinociception with repeated testing, there was no evidence of tolerance when morphine- and saline-treated rats with hind paw inflammation were tested with cumulative doses of morphine. In contrast, repeated morphine injections into the vlPAG caused a rightward shift in the morphine dose-response curve in rats without hind paw inflammation, as would be expected with the development of tolerance. The lack of tolerance in complete Freund's adjuvant-treated rats was evident whether rats were exposed to repeated behavioral testing or not (experiment 2) and whether they were treated with 4 or 8 prior microinjections of morphine into the vlPAG (experiment 3). These data demonstrate that chronic inflammatory pain does not disrupt the antinociceptive effect of microinjecting morphine into the vlPAG, but it does disrupt the development of tolerance. PERSPECTIVE The present data show that induction of chronic inflammatory pain does not disrupt the antinociceptive effect of microinjecting morphine into the vlPAG, but it does attenuate the development of tolerance. This finding indicates that tolerance to opioids in rats with inflammatory pain is mediated by structures other than the vlPAG.
Collapse
Affiliation(s)
- Melissa L Mehalick
- Department of Psychology, Washington State University Vancouver, Vancouver, Washington.
| | | | | | | |
Collapse
|
10
|
Quesseveur G, Repérant C, David DJ, Gardier AM, Sanchez C, Guiard BP. 5-HT2A receptor inactivation potentiates the acute antidepressant-like activity of escitalopram: involvement of the noradrenergic system. Exp Brain Res 2013; 226:285-95. [DOI: 10.1007/s00221-013-3434-3] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2012] [Accepted: 01/25/2013] [Indexed: 11/30/2022]
|
11
|
Quesseveur G, Nguyen HT, Gardier AM, Guiard BP. 5-HT2 ligands in the treatment of anxiety and depression. Expert Opin Investig Drugs 2012; 21:1701-25. [PMID: 22917059 DOI: 10.1517/13543784.2012.719872] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
INTRODUCTION One third of depressed patients do not respond adequately to conventional antidepressants including the selective serotonin reuptake inhibitors (SSRIs). Therefore, multi-target drugs or augmentation strategies have been developed for the management of SSRIs-resistant patients. In this context, the 5-HT(2) receptor subtypes represent promising targets but their precise roles have yet to be determined. AREAS COVERED The aim of this review is to shed some light on the preclinical evidence supporting the use of 5-HT(2A) and/or 5-HT(2C) receptor antagonists such as antipsychotics, as potential effective adjuncts in SSRIs-resistant depression. This review synthesizes the current literature about the behavioral, electrophysiological and neurochemical effects of 5-HT(2) receptors ligands on the monoaminergic systems but also on adult hippocampal neurogenesis. EXPERT OPINION Although studies support the hypothesis that the inactivation of 5-HT(2A) and/or 5-HT(2C) receptors might be of interest to reinforce different facets of the therapeutic activity of SSRIs, this pharmacological strategy remains debatable notably because of the lack of chronic data in relevant animal models. Conversely, emerging evidence suggests that the activation of 5-HT(2B) receptor is required for antidepressant-like activity, opening the way to new therapeutic approaches. However, the potential risks related to the enhancement of monoaminergic neurotransmissions could represent a major concern.
Collapse
Affiliation(s)
- Gaël Quesseveur
- EA3544 University Paris-XI, Laboratoire de Neuropharmacologie, Fac. Pharmacie, F-92296, Châtenay-Malabry cedex, France
| | | | | | | |
Collapse
|
12
|
Effect of chronic pain on morphine-induced respiratory depression in mice. Neuroscience 2010; 174:224-33. [PMID: 21081158 DOI: 10.1016/j.neuroscience.2010.11.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2010] [Revised: 11/08/2010] [Accepted: 11/09/2010] [Indexed: 11/24/2022]
Abstract
Respiratory depression is the most well-known and dangerous side-effect of opioid analgesics. Clinical investigations have revealed that this opioid-induced respiratory depression is less severe in patients with chronic pain, but the mechanisms that underlie this phenomenon are unknown. Therefore, the present study was designed to examine the influence of chronic pain on morphine-induced respiratory depression. Respiration was detected by double-chamber, flow-through whole-body plethysmography. Respiratory frequency was dose-dependently and significantly decreased after morphine administration. This effect peaked at 30 min after administration and lasted 3 h. In contrast, tidal volume was increased. Minute volume was significantly decreased by morphine at a higher dose, but not a lower dose. In nerve-ligated mice, a morphine-induced decrease in respiratory frequency was observed, whereas the increase of tidal volume was more prominent. A decrease in minute volume was not observed in nerve-ligated mice. This attenuation of the morphine-induced decrease in minute volume in nerve-ligated mice was reversed by treatment with the serotonin (5-HT)4a receptor antagonist GR125487. Moreover, treatment with the 5-HT4 receptor agonist mosapride antagonized the morphine-induced decrease in minute volume, due to the enhancement of tidal volume. Finally, the expression of 5-HT4a receptor in the brainstem was enhanced in nerve-ligated mice compared to that in sham-operated mice. These results suggest that the decrease in morphine-induced respiratory depression under chronic pain is mediated by the enhancement of 5-HT4a receptor systems in the brainstem.
Collapse
|
13
|
Liu Q, Wong-Riley MTT. Postnatal changes in the expressions of serotonin 1A, 1B, and 2A receptors in ten brain stem nuclei of the rat: implication for a sensitive period. Neuroscience 2009; 165:61-78. [PMID: 19800944 DOI: 10.1016/j.neuroscience.2009.09.078] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2009] [Revised: 09/25/2009] [Accepted: 09/28/2009] [Indexed: 01/08/2023]
Abstract
A critical period in respiratory network development occurs in the rat around postnatal days (P) 12-13, when abrupt neurochemical, metabolic, and physiological changes were evident. As serotonin and its receptors are involved in respiratory modulation, and serotonergic abnormality is implicated in sudden infant death syndrome, we hypothesized that 5-HT receptors are significantly downregulated during the critical period. This was documented recently for 5-HT(2A)R in several respiratory nuclei. The present study represents a comprehensive analysis of postnatal development of 5-HT(1A)R and 5-HT(1B)R in 10 brain stem nuclei and 5-HT(2A)R in six nuclei not previously examined. Optical densitometric analysis of immunohistochemically-reacted neurons from P2 to P21 indicated four developmental patterns of expression: (1) Pattern I: a high level of expression at P2-P11, an abrupt and significant reduction at P12, followed by a plateau until P21 (5-HT(1A)R and 5-HT(1B)R in raphé magnus [RM], raphé obscurus [ROb], raphé pallidus [RP], pre-Bötzinger complex [PBC], nucleus ambiguus [Amb], and hypoglossal nucleus [XII; 5-HT(1A)R only]). (2) Pattern II: a high level at P2-P9, a gradual decline from P9 to P12, followed by a plateau until P21 (5-HT(1A)R and 5-HT(1B)R in the retrotrapezoid nucleus (RTN)/parafacial respiratory group (pFRG)). (3) Pattern III: a high level at P2-P11, followed by a gradual decline until P21 (5-HT(1A)R in the ventrolateral subnucleus of solitary tract nucleus [NTS(VL)] and the non-respiratory cuneate nucleus [CN]). (4) Pattern IV: a relatively constant level maintained from P2 to P21 (5-HT(1A)R in the commissural subnucleus of solitary tract nucleus (NTS(COM)); 5-HT(1B)R in XII, NTS(VL), NTS(COM), and CN; and 5-HT(2A)R in RM, ROb, RP, RTN/pFRG, NTS(VL), and NTS(COM)). Thus, a significant reduction in the expression of 5-HT(1A)R, 5-HT(1B)R, and 5-HT(2A)R in multiple respiratory-related nuclei at P12 is consistent with reduced serotonergic transmission during the critical period, thereby rendering the animals less able to respond adequately to ventilatory distress.
Collapse
Affiliation(s)
- Q Liu
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, 53226, USA
| | | |
Collapse
|
14
|
Xie H, Dong ZQ, Ma F, Bauer WR, Wang X, Wu GC. Involvement of serotonin 2A receptors in the analgesic effect of tramadol in mono-arthritic rats. Brain Res 2008; 1210:76-83. [DOI: 10.1016/j.brainres.2008.02.049] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2007] [Revised: 02/11/2008] [Accepted: 02/15/2008] [Indexed: 11/27/2022]
|
15
|
Pinto M, Lima D, Tavares I. Neuronal activation at the spinal cord and medullary pain control centers after joint stimulation: a c-fos study in acute and chronic articular inflammation. Neuroscience 2007; 147:1076-89. [PMID: 17590519 DOI: 10.1016/j.neuroscience.2007.05.019] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2007] [Revised: 05/15/2007] [Accepted: 05/18/2007] [Indexed: 01/24/2023]
Abstract
Chronic inflammatory pain induces short- and long-term central changes, which have been mainly studied at the spinal cord level. Supraspinal pain control centers intrinsically connected with the dorsal horn are also prone to be affected by chronic inflammatory pain. C-fos expression was used as a neuronal activation marker at spinal and supraspinal levels to i) compare acute and chronic articular inflammation, and ii) analyze the effects of brief innocuous or noxious stimulation of a chronically inflamed joint. Acute articular inflammation was induced by an inflammatory soup with prostaglandin E(2) and bradykinin, both at 10(-5) M. Chronic articular inflammation consisted of 14 days of monoarthritis. Early c-fos expression was studied 4 min after inflammatory soup injection or stimulation of the arthritic joint whereas late c-fos expression was evaluated 2 h after those stimuli. At the spinal cord, the analysis was focused on the dorsal horn (laminae I-V) and supraspinally, five major regions of the endogenous pain control system were considered: the caudal ventrolateral medulla (VLM), the dorsal reticular nucleus (DRt), the ventral reticular nucleus (VRt), the nucleus of the solitary tract (Sol) and the rostroventromedial medulla (RVM). Acute articular inflammation induced early and late increases in c-fos expression at the spinal level and late increases supraspinally whereas the effects of monoarthritis were more moderate and restricted to the spinal cord. When monoarthritic animals were subjected to gentle touch or bending of the joint, early increases in c-fos expression were detected supraspinally, but not at the spinal level. In this region, noxious mechanical stimulation induced late increases in non-inflamed animals and both early and late increases in monoarthritic rats. Supraspinally, noxious stimulation induced only late increases in c-fos expression. The present results show complex differences in the patterns of c-fos expression between the spinal cord and medullary areas of the pain control system during articular inflammation, which indicate that the somatosensory system is differentially affected by the installation of chronic pain.
Collapse
Affiliation(s)
- M Pinto
- Institute of Histology and Embryology, Faculdade de Medicina, Universidade do Porto, Alameda Hernâni Monteiro, 4200-319 Porto, Portugal
| | | | | |
Collapse
|
16
|
Okamoto K, Kimura A, Donishi T, Imbe H, Nishie Y, Matsushita H, Tamai Y, Senba E. Contribution of peripheral 5-HT2A or 5-HT3 receptors to Fos expression in the trigeminal spinal nucleus produced by acute injury to the masseter muscle during persistent temporomandibular joint inflammation in rats. Neuroscience 2006; 143:597-606. [PMID: 16979827 DOI: 10.1016/j.neuroscience.2006.08.009] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2006] [Revised: 07/17/2006] [Accepted: 08/07/2006] [Indexed: 12/30/2022]
Abstract
We investigated the contribution of peripheral 5-HT2A or 5-HT3 receptors to Fos expression in the trigeminal spinal nucleus (VSP) following acute masseter muscle injury in male rats with or without temporomandibular joint (TMJ) inflammation persisting for 7 days. TMJ inflammation was evoked by an injection of complete Freund's adjuvant (CFA). Two hours after formalin injection into the masseter muscle produced Fos-like immunoreactivity (Fos-LI) in several regions of the VSP and upper cervical spinal cord (C2), such as ventrolateral (vl) area of the trigeminal subnucleus caudalis (Vc)/subnucleus interpolaris (Vi) transition (vl-Vi/Vc), paratrigeminal nucleus (dPa5), middle portion of the Vc (mid-Vc) and Vc/C2 transition (Vc/C2) regions in both groups. Significant increases in the number of Fos-LI were observed in these areas in CFA group compared with non-CFA group. TMJ inflammation alone did not induce a significant level of Fos-LI in the VSP. In order to assess the effect of antagonizing 5-HT2A or 5-HT3 receptors on formalin-induced Fos-LI, rats were pre-treated with local (masseter muscle) administration of ketanserin or tropisetron (0.01, 0.1 mg/rat) 20 min prior to formalin injection. In CFA group, these antagonists given locally reduced the Fos-LI response in the laminae I-II at the mid-Vc and Vc/C2 regions. These antagonists reduced the Fos-LI response in the dPa5, but not in the vl-Vi/Vc region. The Fos-LI response was not affected by i.v. administration of ketanserin (0.01, 0.1 mg/rat) or tropisetron (0.01 mg/rat). In non-CFA group, these antagonists given locally did not reduce the Fos-LI response. These results suggest that peripheral 5-HT2A and 5-HT3 receptors contribute to nociceptive processing in the masseter muscle in TMJ inflammatory conditions.
Collapse
Affiliation(s)
- K Okamoto
- Department of Physiology, Wakayama Medical University, Wakayama City 641-8509, Japan.
| | | | | | | | | | | | | | | |
Collapse
|
17
|
Cook CD, Nickerson MD. Nociceptive sensitivity and opioid antinociception and antihyperalgesia in Freund's adjuvant-induced arthritic male and female rats. J Pharmacol Exp Ther 2004; 313:449-59. [PMID: 15608071 DOI: 10.1124/jpet.104.077792] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The present study was designed to examine sex differences in complete Freund's adjuvant (CFA)-induced mechanical hyperalgesia and sex differences in opioid antinociception and anti-hyperalgesia. Female rats developed inflammation and hyperalgesia faster and exhibited greater peak hyperalgesia than male rats. In arthritic (CFA-treated) rats, lower thresholds were observed during estrus and proestrus, and in nonarthritic (vehicle-treated) rats, lower thresholds were observed during proestrus. Morphine and oxycodone were more potent in male than female arthritic rats, and butorphanol was more potent and effective in male than female arthritic rats. The potency of morphine was increased in arthritic rats, although to a greater magnitude in males. The potency of oxycodone was increased in male but not female arthritic rats. The potency of butorphanol was increased in arthritic male rats and the maximal antinociceptive effect of butorphanol was increased in arthritic female rats, but it did not result in greater than 20% antinociception. Morphine, oxycodone, and butorphanol all produced antihyperalgesic effects (returning thresholds of arthritic rats to the thresholds of nonarthritic rats) with greater potency in males than females. The peripherally acting opioid agonist loperamide produced intermediate levels of antinociception in male and female arthritic rats and no antinociception in nonarthritic rats. Loperamide was more potent in male than female arthritic rats at producing antihyperalgesia. These data demonstrate sex differences in arthritis-induced hyperalgesia and responsiveness to opioid analgesics. In arthritic rats, the antinociceptive effects of opioid agonists are most probably mediated by both central and peripheral opioid receptors, whereas their antihyperalgesic effects are mediated primarily by actions at peripheral opioid receptors.
Collapse
Affiliation(s)
- Charles D Cook
- Department of Pharmacology and Toxicology and Institute for Drug and Alcohol Studies, Virginia Commonwealth University, Richmond, VA 23298-0613, USA.
| | | |
Collapse
|
18
|
Ma F, Xie H, Dong ZQ, Wang YQ, Wu GC. Effects of electroacupuncture on orphanin FQ immunoreactivity and preproorphanin FQ mRNA in nucleus of raphe magnus in the neuropathic pain rats. Brain Res Bull 2004; 63:509-13. [PMID: 15249116 DOI: 10.1016/j.brainresbull.2004.04.011] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2004] [Revised: 03/31/2004] [Accepted: 04/15/2004] [Indexed: 11/27/2022]
Abstract
Orphanin FQ (OFQ) is an endogenous ligand for opioid receptor-like-1 (ORL1) receptor. Previous studies have shown that both OFQ immunoreactivity and preproorphanin FQ (ppOFQ) mRNA expression could be observed in the brain regions involved in pain modulation, e.g., nucleus of raphe magnus (NRM), dorsal raphe nucleus (DRN), and ventrolateral periaqueductal gray (vlPAG). It was reported that electroacupuncture (EA) has analgesic effect on neuropathic pain, and the analgesic effect was mediated by the endogenous opioid peptides. In the present study, we investigated the effects of EA on the changes of OFQ in the neuropathic pain rats. In the sciatic nerve chronic constriction injury (CCI) model, we investigated the changes of ppOFQ mRNA and OFQ immunoreactivity in NRM after EA by in situ hybridization (ISH) and immunohistochemistry methods, respectively. Then, the ppOFQ mRNA-positive and OFQ immunoreactive cells were counted under a computerized image analysis system. The results showed that expression of ppOFQ mRNA decreased and OFQ immunoreactivity increased after EA treatment in the neuropathic pain rats. These results indicated that EA modulated OFQ synthesis and OFQ peptide level in NRM of the neuropathic pain rats.
Collapse
Affiliation(s)
- Fei Ma
- Department of Integrative Medicine, Institute of Acupuncture Research, Shanghai Medical College, Fudan University, P.O. Box 291, 138 Yi Xue Yuan Road, Shanghai 200032, China
| | | | | | | | | |
Collapse
|