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Tanwar S, Mattoo B, Kumar U, Dada R, Bhatia R. Does human serotonin-1A receptor polymorphism (rs6295) code for pain and associated symptoms in fibromyalgia syndrome? Reumatismo 2021; 73:24-31. [PMID: 33874644 DOI: 10.4081/reumatismo.2021.1312] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Accepted: 02/23/2021] [Indexed: 11/22/2022] Open
Abstract
Genetic predisposition may play an important role in the development of fibromyalgia syndrome (FMS). Serotonin is known to be involved in pain modulation and serotonin-1A receptor plays a considerable role in determining the central 5-HT tone. Consequently, variation in 5-HT1A receptor gene (HTR1A) may be responsible for inter-individual variability in pain sensitivity and other clinical symptoms of FMS. Therefore, the objectives of this research work were to study the gene polymorphism of 5-HTR1A gene and to explore the correlation between rs6295 genotype (-1019C/G HTR1A) and duration of pain, pain intensity and pain related depression and anxiety, if any, in FMS. 5-HTR1A genotype for the C(-1019)G polymorphism was typed in 62 patients with FMS and 42 healthy subjects. Present pain intensity, components of pain and pain related depression and anxiety were assessed using the numerical pain rating scale, McGill pain questionnaire and Hamilton depression and anxiety rating scale respectively. 5-HTR1A gene was represented by three different genotypes, homozygous C/C, heterozygous C/G and homozygous G/G. Analysis of the 5-HTR1A gene showed a frequency of 58%, 31% and 11% for the C/C, C/G and G/G genotypes, respectively in FMS group. This proportion was 69%, 23% and 8% in healthy subjects. No significant correlation was observed between 5-HTR1A gene polymorphism and pain and related symptoms in FMS patients. To the best of our knowledge this is the first study which investigated the correlation between the 5-HTR1A gene polymorphism and pain intensity, the affective component of pain, pain related depression and anxiety in FMS.
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Affiliation(s)
- S Tanwar
- Department of Physiology, All India Institute of Medical Sciences (AIIMS), New Delhi.
| | - B Mattoo
- Department of Physiology, All India Institute of Medical Sciences (AIIMS), New Delhi.
| | - U Kumar
- Department of Rheumatology, All India Institute of Medical Sciences (AIIMS), New Delhi.
| | - R Dada
- Department of Anatomy, All India Institute of Medical Sciences (AIIMS), New Delhi.
| | - R Bhatia
- Department of Physiology, All India Institute of Medical Sciences (AIIMS), New Delhi.
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2
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de Moura FB, Bergman J. Enhancement of Opioid Antinociception by Nicotinic Ligands. J Pharmacol Exp Ther 2021; 377:100-107. [PMID: 33441370 DOI: 10.1124/jpet.120.000423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Accepted: 01/11/2021] [Indexed: 11/22/2022] Open
Abstract
Nicotine has previously been shown to augment the antinociceptive effects of μ-opioid agonists in squirrel monkeys without producing a concomitant increase in behavioral disruption. The present studies were conducted to extend these findings by determining the ability of the nicotinic acetylcholine receptor (nAChR) agonist epibatidine and partial α4β2 nAChR agonist varenicline to selectively augment the antinociceptive effects of the μ-opioid receptor (MOR) full agonist fentanyl, the MOR partial agonist nalbuphine, and the κ-opioid receptor (KOR) agonist U69,593 in male squirrel monkeys. Results indicate that both nAChR ligands selectively increased the antinociceptive effects of nalbuphine and that epibatidine increased the antinociceptive effects of U69,593 without altering effects on operant behavior. However, neither epibatidine nor varenicline enhanced the antinociceptive effects of fentanyl, perhaps due to its high efficacy. The enhancement of nalbuphine's antinociceptive effects by epibatidine, but not varenicline, could be antagonized by either mecamylamine or dihydro-β-erythroidine, consistent with α4β2 mediation of epibatidine's effects but suggesting the involvement of non-nAChR mechanisms in the effects of varenicline. The present results support previous findings showing that an nAChR agonist can serve as an adjuvant for MOR antinociception and, based on results with U69,593, further indicate that the adjuvant effects of nAChR drugs may also apply to antinociception produced by KOR. Our findings support the further evaluation of nAChR agonists as adjuvants of opioid pharmacotherapy for pain management and point out the need for further investigation into the mechanisms by which they produce opioid-adjuvant effects. SIGNIFICANCE STATEMENT: Nicotine has been shown to augment the antinociceptive effects of μ-opioid receptor analgesics without exacerbating their effects on operant performance. The present study demonstrates that the nicotinic acetylcholine receptor (nAChR) agonist epibatidine and partial α4β2 nAChR agonist varenicline can also augment the antinociceptive effects of nalbuphine, as well as those of a κ-opioid receptor agonist, without concomitantly exacerbating their behaviorally disruptive effects. These findings support the view that nAChR agonists and partial agonists may have potential as adjuvant therapies for opioid-based analgesics.
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Affiliation(s)
- Fernando B de Moura
- Behavioral Biology Program, McLean Hospital, Belmont, Massachusetts and Department of Psychiatry, Harvard Medical School, Boston, Massachusetts
| | - Jack Bergman
- Behavioral Biology Program, McLean Hospital, Belmont, Massachusetts and Department of Psychiatry, Harvard Medical School, Boston, Massachusetts
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3
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Ernberg M, Wieslander Fältmars A, Hajizadeh Kopayeh M, Arzt Wallén S, Cankalp T, Christidis N. The Effect of Granisetron on Sensory Detection and Pain Thresholds in Facial Skin of Healthy Young Males. Front Neurol 2020; 11:237. [PMID: 32328025 PMCID: PMC7161671 DOI: 10.3389/fneur.2020.00237] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Accepted: 03/12/2020] [Indexed: 12/16/2022] Open
Abstract
Background: The specific serotonin type 3 (5-HT3)-receptor antagonist granisetron effectively reduces clinical as well as experimental muscle pain and hyperalgesia and with a duration that exceeds that of lidocaine. Hence, it may be an alternative to lidocaine as a local anesthetic. There are also some indications that granisetron in addition to 5-HT3 receptors blocks sodium channels. Thus, the local anesthetic effect by granisetron may resemble that of lidocaine, but this has not been tested. The aim of this study was therefore to compare the effect granisetron has on facial skin sensitivity to the effect of lidocaine and isotonic saline. Methods: This was a randomized, controlled, and double-blind study, in which 1 ml of either granisetron (test-substance), lidocaine (positive control), or isotonic saline (negative control) was injected into the skin over the masseter muscle at three different occasions in 18 healthy males (27.2 ± 5.8 years old). Skin detection thresholds and pain thresholds for thermal stimuli as well as mechanical detection thresholds and sensitivity to a painful mechanical (pinprick) stimulus were assessed before (baseline) and 5, 20, 40, and 60 min after injection. The quality and area of subjective sensory change over the cheek were assessed 20 min after injection. Results: All substances increased the mechanical detection threshold (granisetron: p = 0.011; lidocaine: p = 0.016; saline: p = 0.031). Both granisetron and lidocaine, but not isotonic saline, increased the heat detection thresholds (p < 0.001 and p < 0.02, respectively), but not the cold detection thresholds. Granisetron and lidocaine also reduced pinprick pain (p = 0.001 for each comparison). There were no significant differences between granisetron and lidocaine for any of these variables. There was no effect on thermal pain thresholds for any substance. Conclusion: The similar analgesic patterns on mechanical sensory and pain thresholds as well as thermal sensory thresholds over the facial skin by subcutaneous injection of granisetron and lidocaine shown in this study and the absence of paresthesia, in combination with the reduced pain intensity and pressure pain sensitivity shown in previous studies, indicate that granisetron might be a novel candidate as a local anesthetic.
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Affiliation(s)
- Malin Ernberg
- Division of Oral Diagnostics and Rehabilitation, Department of Dental Medicine, Karolinska Institutet, and Scandinavian Center for Orofacial Neuroscience (SCON), Huddinge, Sweden
| | - Anna Wieslander Fältmars
- Division of Oral Diagnostics and Rehabilitation, Department of Dental Medicine, Karolinska Institutet, and Scandinavian Center for Orofacial Neuroscience (SCON), Huddinge, Sweden
| | - Milad Hajizadeh Kopayeh
- Division of Oral Diagnostics and Rehabilitation, Department of Dental Medicine, Karolinska Institutet, and Scandinavian Center for Orofacial Neuroscience (SCON), Huddinge, Sweden
| | - Sofia Arzt Wallén
- Division of Oral Diagnostics and Rehabilitation, Department of Dental Medicine, Karolinska Institutet, and Scandinavian Center for Orofacial Neuroscience (SCON), Huddinge, Sweden
| | - Therese Cankalp
- Division of Oral Diagnostics and Rehabilitation, Department of Dental Medicine, Karolinska Institutet, and Scandinavian Center for Orofacial Neuroscience (SCON), Huddinge, Sweden
| | - Nikolaos Christidis
- Division of Oral Diagnostics and Rehabilitation, Department of Dental Medicine, Karolinska Institutet, and Scandinavian Center for Orofacial Neuroscience (SCON), Huddinge, Sweden
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4
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Okamoto K, Katagiri A, Rahman M, Thompson R, Bereiter DA. Inhibition of temporomandibular joint input to medullary dorsal horn neurons by 5HT3 receptor antagonist in female rats. Neuroscience 2015; 299:35-44. [PMID: 25913635 DOI: 10.1016/j.neuroscience.2015.04.037] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2015] [Revised: 03/17/2015] [Accepted: 04/16/2015] [Indexed: 12/19/2022]
Abstract
Repeated forced swim (FS) conditioning enhances nociceptive responses to temporomandibular joint (TMJ) stimulation in female rats. The basis for FS-induced TMJ hyperalgesia remains unclear. To test the hypothesis that serotonin 3 receptor (5HT3R) mechanisms contribute to enhanced TMJ nociception after FS, ovariectomized female rats were treated with estradiol and subjected to FS for three days. On day 4, rats were anesthetized with isoflurane and TMJ-responsive neurons were recorded from superficial and deep laminae at the trigeminal subnucleus caudalis/upper cervical (Vc/C1-2) region and electromyographic (EMG) activity was recorded from the masseter muscle. Only Vc/C1-2 neurons activated by intra-TMJ injections of ATP were included for further analysis. Although neurons in both superficial and deep laminae were activated by ATP, only neurons in deep laminae displayed enhanced responses after FS. Local application of the 5HT3R antagonist, ondansetron (OND), at the Vc/C1-2 region reduced the ATP-evoked responses of neurons in superficial and deep laminae and reduced the EMG response in both sham and FS rats. OND also decreased the spontaneous firing rate of neurons in deep laminae and reduced the high-threshold convergent cutaneous receptive field area of neurons in superficial and deep laminae in both sham and FS rats. These results revealed that central application of a 5HT3R antagonist, had widespread effects on the properties of TMJ-responsive neurons at the Vc/C1-2 region and on jaw muscle reflexes under sham and FS conditions. It is concluded that 5HT3R does not play a unique role in mediating stress-induced hyperalgesia related to TMJ nociception.
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Affiliation(s)
- K Okamoto
- Department of Diagnostic and Biological Sciences, University of Minnesota School of Dentistry, Minneapolis, MN 55455, United States.
| | - A Katagiri
- Department of Diagnostic and Biological Sciences, University of Minnesota School of Dentistry, Minneapolis, MN 55455, United States
| | - M Rahman
- Department of Diagnostic and Biological Sciences, University of Minnesota School of Dentistry, Minneapolis, MN 55455, United States
| | - R Thompson
- Department of Diagnostic and Biological Sciences, University of Minnesota School of Dentistry, Minneapolis, MN 55455, United States
| | - D A Bereiter
- Department of Diagnostic and Biological Sciences, University of Minnesota School of Dentistry, Minneapolis, MN 55455, United States
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5
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Amato A, Serio R, Mulè F. Involvement of cholinergic nicotinic receptors in the menthol-induced gastric relaxation. Eur J Pharmacol 2014; 745:129-34. [PMID: 25446932 DOI: 10.1016/j.ejphar.2014.10.012] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2014] [Revised: 09/16/2014] [Accepted: 10/05/2014] [Indexed: 02/06/2023]
Abstract
We have previously demonstrated that menthol reduces murine gastric tone in part through a neural mechanism, involving adrenergic pathways and reduction of ongoing release of acetylcholine from enteric nerves. In the present study we aimed to verify whether the gastric relaxation to menthol may be triggered by interaction with neural receptors or ionic channels proteins, such as transient receptor potential (TRP)-melastatin8 (TRPM8), TRP-ankyrin 1 (TRPA1), 5-hydroxytriptamine 3 (5-HT3) receptor or cholinergic nicotinic receptors. Spontaneous mechanical activity was detected in vitro as changes in intraluminal pressure from isolated mouse stomach. Menthol (0.3-30 mM) induced gastric relaxation which was not affected by 5-benzyloxytryptamine, a TRPM8 receptor antagonist, HC030031, a TRPA1 channel blocker. In addition, allylisothiocyanate, a TRPA1 agonist, but not (2S,5R)-2-Isopropyl-N-(4-methoxyphenyl)-5-methylcyclohexanecarboximide, a selective TRPM8 agonist, induced gastric relaxation. Genic expression of TRPA1, but not of TRPM8, was revealed in mouse stomach. Indeed, menthol-induced gastric relaxation was significantly reduced by hexamethonium, cholinergic nicotinic receptor antagonist. Menthol, at concentrations that failed to affect gastric tone, reduced the contraction induced by dimethylphenylpiperazinium, nicotinic receptor agonist. The joint application of hexamethonium and atropine, muscarinc receptor antagonist, or hexamethonium and phentholamine, α-adrenergic receptor antagonist, did not produce any additive reduction of the relaxant response to menthol. Lastly, ondansetron, a 5-HT3 receptor antagonist, was ineffective. In conclusion, our study suggests that nicotinic receptors, but not TRP and 5-HT3 receptors, are molecular targets for menthol inducing murine gastric relaxation, ultimately due to the reduction of acetylcholine release from enteric nerves.
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Affiliation(s)
- Antonella Amato
- Dipartimento di Scienze e Tecnologie Biologiche, Chimiche e Farmaceutiche (STEBICEF), Università di Palermo, 90128 Palermo, Italy.
| | - Rosa Serio
- Dipartimento di Scienze e Tecnologie Biologiche, Chimiche e Farmaceutiche (STEBICEF), Università di Palermo, 90128 Palermo, Italy
| | - Flavia Mulè
- Dipartimento di Scienze e Tecnologie Biologiche, Chimiche e Farmaceutiche (STEBICEF), Università di Palermo, 90128 Palermo, Italy
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6
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Ashoor A, Nordman JC, Veltri D, Yang KHS, Shuba Y, Al Kury L, Sadek B, Howarth FC, Shehu A, Kabbani N, Oz M. Menthol inhibits 5-HT3 receptor-mediated currents. J Pharmacol Exp Ther 2013; 347:398-409. [PMID: 23965380 DOI: 10.1124/jpet.113.203976] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
The effects of alcohol monoterpene menthol, a major active ingredient of the peppermint plant, were tested on the function of human 5-hydroxytryptamine type 3 (5-HT3) receptors expressed in Xenopus laevis oocytes. 5-HT (1 μM)-evoked currents recorded by two-electrode voltage-clamp technique were reversibly inhibited by menthol in a concentration-dependent (IC50 = 163 μM) manner. The effects of menthol developed gradually, reaching a steady-state level within 10-15 minutes and did not involve G-proteins, since GTPγS activity remained unaltered and the effect of menthol was not sensitive to pertussis toxin pretreatment. The actions of menthol were not stereoselective as (-), (+), and racemic menthol inhibited 5-HT3 receptor-mediated currents to the same extent. Menthol inhibition was not altered by intracellular 1,2-bis(o-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid injections and transmembrane potential changes. The maximum inhibition observed for menthol was not reversed by increasing concentrations of 5-HT. Furthermore, specific binding of the 5-HT3 antagonist [(3)H]GR65630 was not altered in the presence of menthol (up to 1 mM), indicating that menthol acts as a noncompetitive antagonist of the 5-HT3 receptor. Finally, 5-HT3 receptor-mediated currents in acutely dissociated nodose ganglion neurons were also inhibited by menthol (100 μM). These data demonstrate that menthol, at pharmacologically relevant concentrations, is an allosteric inhibitor of 5-HT3 receptors.
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Affiliation(s)
- Abrar Ashoor
- Laboratory of Functional Lipidomics, Departments of Pharmacology (A.A., L.A.K., B.S., M.O.) and Physiology (F.C.H.), College of Medicine and Health Sciences, UAE University, Al Ain, United Arab Emirates; Department of Molecular Neuroscience (J.C.N., N.K.), School of Systems Biology (D.V.), and Department of Computer Science (A.S.), George Mason University, Fairfax, Virginia; International Center of Molecular Physiology of the National Academy of Sciences of Ukraine, Kiev, Ukraine (Y.S.); and Department of Biological Sciences, Schmid College of Science and Engineering, Chapman University, Orange, California (K.-H.S.Y.)
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7
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Louca S, Ernberg M, Christidis N. Influence of intramuscular granisetron on experimentally induced muscle pain by acidic saline. J Oral Rehabil 2013; 40:403-12. [DOI: 10.1111/joor.12046] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/14/2013] [Indexed: 12/01/2022]
Affiliation(s)
- S. Louca
- Section for Orofacial Pain and Jaw Function; Department of Dental Medicine; Karolinska Institutet; Huddinge Sweden
| | - M. Ernberg
- Section for Orofacial Pain and Jaw Function; Department of Dental Medicine; Karolinska Institutet; Huddinge Sweden
| | - N. Christidis
- Section for Orofacial Pain and Jaw Function; Department of Dental Medicine; Karolinska Institutet; Huddinge Sweden
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8
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Paola Mascia M, Fabbri D, Antonietta Dettori M, Ledda G, Delogu G, Biggio G. Hydroxylated biphenyl derivatives are positive modulators of human GABA(A) receptors. Eur J Pharmacol 2012; 693:45-50. [PMID: 22959356 DOI: 10.1016/j.ejphar.2012.07.048] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2011] [Revised: 07/19/2012] [Accepted: 07/30/2012] [Indexed: 11/17/2022]
Abstract
A series of 7 hydroxylated biphenyl derivatives (1-7) were prepared to evaluate their ability to modulate the function of several ligand gated ion channel (LGIC) recombinant receptors expressed in Xenopus laevis oocytes. Compounds 1, 3, 4, 6 and 7 are natural occurring compounds whereas the synthesis of compounds 2 and 5 was previously reported (Delogu et al., 2004; Fabbri et al., 2007). None of the compounds tested were able to modify, the activity of the strychnine-sensitive glycine receptor, or the activity of nicotinic receptor. The function of the 5HT(3A) receptor was partially inhibited by all compounds tested, however this inhibition occurred at relatively high concentrations (100 μM). All compounds, with the exception of compound 6, potentiate the action of gamma-aminobutyric acid (GABA)-evoked Cl(-) currents in Xenopus laevis oocytes expressing recombinant human α(1)β(2)γ(2L) GABA(A) receptors. Compounds 1, 2, 5 and 7 enhance the function of the GABA(A) receptor at concentrations higher than 3-10 μM. Compound 4 was the most efficacious. However, compound 3 was the most potent (EC(50) 0.8 μM). The potency of compound 3 in modulating the function of the GABA(A) receptor was comparable to that of diazepam, propofol or allopregnanolone. The enhancement of the GABA evoked Cl(-) currents by compound 3 was not affected by flumazenil. Compound 3 did not induce loss of the righting reflex in rats suggesting that it is not an anesthetic agent, however, its ability in protecting the animals from seizures induced by picrotoxin confirm that its action occurs through the GABA(A) receptor.
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Affiliation(s)
- Maria Paola Mascia
- CNR-Institute of Neuroscience, Cagliari, Cittadella Universitaria, 09042 Monserrato, Italy.
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9
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Olesen AE, Andresen T, Staahl C, Drewes AM. Human experimental pain models for assessing the therapeutic efficacy of analgesic drugs. Pharmacol Rev 2012; 64:722-79. [PMID: 22722894 DOI: 10.1124/pr.111.005447] [Citation(s) in RCA: 156] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Pain models in animals have shown low predictivity for analgesic efficacy in humans, and clinical studies are often very confounded, blurring the evaluation. Human experimental pain models may therefore help to evaluate mechanisms and effect of analgesics and bridge findings from basic studies to the clinic. The present review outlines the concept and limitations of human experimental pain models and addresses analgesic efficacy in healthy volunteers and patients. Experimental models to evoke pain and hyperalgesia are available for most tissues. In healthy volunteers, the effect of acetaminophen is difficult to detect unless neurophysiological methods are used, whereas the effect of nonsteroidal anti-inflammatory drugs could be detected in most models. Anticonvulsants and antidepressants are sensitive in several models, particularly in models inducing hyperalgesia. For opioids, tonic pain with high intensity is attenuated more than short-lasting pain and nonpainful sensations. Fewer studies were performed in patients. In general, the sensitivity to analgesics is better in patients than in healthy volunteers, but the lower number of studies may bias the results. Experimental models have variable reliability, and validity shall be interpreted with caution. Models including deep, tonic pain and hyperalgesia are better to predict the effects of analgesics. Assessment with neurophysiologic methods and imaging is valuable as a supplement to psychophysical methods and can increase sensitivity. The models need to be designed with careful consideration of pharmacological mechanisms and pharmacokinetics of analgesics. Knowledge obtained from this review can help design experimental pain studies for new compounds entering phase I and II clinical trials.
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Affiliation(s)
- Anne Estrup Olesen
- Mech-Sense, Department of Gastroenterology & Hepatology, Aalborg Hospital, Mølleparkvej 4, 9000 Aalborg, Denmark.
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10
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Potvin S, Larouche A, Normand E, de Souza JB, Gaumond I, Marchand S, Grignon S. No relationship between the ins del polymorphism of the serotonin transporter promoter and pain perception in fibromyalgia patients and healthy controls. Eur J Pain 2012; 14:742-6. [DOI: 10.1016/j.ejpain.2009.12.004] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2009] [Revised: 12/02/2009] [Accepted: 12/19/2009] [Indexed: 11/15/2022]
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11
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Förster M, Baron R. One failed clinical trial (of 5HT3 antagonists) does not invalidate the concept. Pain 2011; 153:263-264. [PMID: 22154218 DOI: 10.1016/j.pain.2011.11.015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2011] [Revised: 11/09/2011] [Accepted: 11/14/2011] [Indexed: 10/14/2022]
Affiliation(s)
- Matti Förster
- Sektion Neurologische Schmerzforschung und -therapie, Klinik für Neurologie, Christian-Albrechts-Universität Kiel, Arnold-Heller-Straße 3, Haus 41, 24105 Kiel, Germany
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12
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Chirumbolo S. Plant-derived extracts in the neuroscience of anxiety on animal models: biases and comments. Int J Neurosci 2011; 122:177-88. [PMID: 22050267 DOI: 10.3109/00207454.2011.635829] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Generalized anxiety disorders probably represent one of the world's biggest mental health problems. A large number of studies have also shown that anxiety disorders and depression are often associated with quality of life impairments. As anxiety represents a big concern in public health, a substantial literature supports clinically important associations between psychiatric illness and chronic medical conditions. Actually, most research focuses on depression, finding that depression can adversely affect self-care and increase the risk of incident medical illness, complications, and mortality. Anxiety disorders are less well studied, but robust epidemiological and clinical evidences show that they play an equally important role. Recent reported articles have raised a debate about the effectiveness of some plant-derived extracts in anxiety-like models in mice. Biases about several aspects related with experimental setting, animal selection, environments, operators and investigators, selection and performance of behavioral tests, controls, results managing, and statistics are here discussed.
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13
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Neziri AY, Dickenmann M, Scaramozzino P, Andersen OK, Arendt-Nielsen L, Dickenson AH, Curatolo M. Effect of intravenous tropisetron on modulation of pain and central hypersensitivity in chronic low back pain patients. Pain 2011; 153:311-318. [PMID: 22100357 DOI: 10.1016/j.pain.2011.10.008] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2011] [Revised: 10/04/2011] [Accepted: 10/05/2011] [Indexed: 10/15/2022]
Abstract
The activation of 5-hydroxytryptamine-3 (5-HT-3) receptors in spinal cord can enhance intrinsic spinal mechanisms of central hypersensitivity, possibly leading to exaggerated pain responses. Clinical studies suggest that 5-HT-3 receptor antagonists may have an analgesic effect. This randomized, double-blind, placebo-controlled crossover study tested the hypothesis that the 5-HT-3 receptor antagonist tropisetron attenuates pain and central hypersensitivity in patients with chronic low back pain. Thirty patients with chronic low back pain, 15 of whom were women (aged 53 ± 14 years) and 15 men (aged 48 ± 14 years), were studied. A single intravenous injection of 0.9% saline solution, tropisetron 2mg, and tropisetron 5mg was administrated in 3 different sessions, in a double-blind crossover manner. The main outcome was the visual analogue scale (VAS) score of spontaneous low back pain before, and 15, 30, 60, and 90 minutes after drug administration. Secondary outcomes were nociceptive withdrawal reflexes to single and repeated electrical stimulation, area of reflex receptive fields, pressure pain detection and tolerance thresholds, conditioned pain modulation, and area of clinical pain. The data were analyzed by analysis of variance and panel multiple regressions. All 3 treatments reduced VAS scores. However, there was no statistically significant difference between tropisetron and placebo in VAS scores. Compared to placebo, tropisetron produced a statistically significant increase in pain threshold after single electrical stimulation, but no difference in all other secondary outcomes was found. A single-dose intravenous administration of tropisetron in patients with chronic low back pain had no significant specific effect on intensity of pain and most parameters of central hypersensitivity.
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Affiliation(s)
- Alban Y Neziri
- University Department of Anaesthesiology and Pain Therapy, Bern University Hospital, Inselspital, Bern 3010, Switzerland Department of Financial and Management Studies, School of Oriental and African Studies, University of London, London, UK Department of Economics and Institutions, University of Rome Tor Vergata, Rome, Italy Center for Sensory-Motor Interaction, Department of Health Science and Technology, Aalborg University, Aalborg, Denmark Department of Pharmacology, University College London, London, UK
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14
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Rahimian R, Dehpour AR, Fakhfouri G, Khorramizadeh MR, Ghia JE, Seyedabadi M, Caldarelli A, Mousavizadeh K, Forouzandeh M, Mehr SE. Tropisetron upregulates cannabinoid CB1 receptors in cerebellar granule cells: Possible involvement of calcineurin. Brain Res 2011; 1417:1-8. [DOI: 10.1016/j.brainres.2011.08.050] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2011] [Revised: 08/18/2011] [Accepted: 08/19/2011] [Indexed: 01/17/2023]
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15
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Seidel MF, Müller W. Differential pharmacotherapy for subgroups of fibromyalgia patients with specific consideration of 5-HT3 receptor antagonists. Expert Opin Pharmacother 2011; 12:1381-91. [PMID: 21323622 DOI: 10.1517/14656566.2011.557362] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
INTRODUCTION The fibromyalgia syndrome (FMS) has a prevalence of about 2% and is characterized by generalized musculoskeletal pain, reduced pain threshold and autonomic and functional symptoms. It is a multifactorial syndrome with four different subgroups exhibiting pathophysiological and psychiatric findings. No precise treatment strategy is currently available for the different FMS subgroups. AREAS COVERED This article reviews the evidence for treatment options for the different FMS subgroups. EXPERT OPINION Therapy for the first subgroup of primary FMS, with high levels of pain but no psychopathological alterations, is targeted at nociceptors expressing serotonin (5-hydroxytryptamine-3; 5-HT3) receptors with 5-HT3 receptor antagonists. The second and third subgroups are characterized by depressive syndromes with a major indication for antidepressants. The fourth subgroup with psychosomatic syndromes requires psychotherapeutic treatment. Secondary FMS is similar to the primary syndromes but is triggered by a variety of other diseases and frequently responds to 5-HT3 receptor antagonist treatment. Different classes of drug, such as pregabalin, must be tested for efficacy and tolerance. FMS treatment strategies should be tailored after the identification of individual FMS subgroups. Although several groups of drug have been studied extensively, 5-HT3 receptor antagonists are most effective in patients without psychopathological alterations.
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Affiliation(s)
- Matthias F Seidel
- Medizinische Klinik und Poliklinik I, Rheumatology Unit, Wilhelmstrasse, Bonn, Germany.
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Yang KHS, Isaev D, Morales M, Petroianu G, Galadari S, Oz M. The effect of Δ9-tetrahydrocannabinol on 5-HT3 receptors depends on the current density. Neuroscience 2010; 171:40-9. [PMID: 20800662 DOI: 10.1016/j.neuroscience.2010.08.044] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2010] [Revised: 08/02/2010] [Accepted: 08/20/2010] [Indexed: 11/26/2022]
Abstract
The effects of Δ(9)-tetrahydrocannabinol (THC), the psychoactive component of cannabis, on the function of 5-HT type 3 (5-HT(3)) receptors were investigated using a two-electrode voltage clamp technique in Xenopus oocytes, and a whole-cell patch clamp technique in rat nodose ganglion neurons. In oocytes injected with 3 ng cRNA of 5-HT(3A) receptor, THC reversibly inhibited currents evoked with 5-HT (1 μM) in a concentration-dependent manner (IC(50)=1.2 μM). The extent of THC inhibition was inversely correlated with the amount of cRNA injected and the mean 5-HT(3A) receptor current densities. Pretreatment with actinomycin D, which inhibits transcription, decreased the mean 5-HT(3) receptor current density and increased the extent of THC inhibition on 5-HT(3) receptor-mediated currents. The IC(50) values for THC increased from 285 nM to 1.2 μM in oocytes injected with 1 and 3 ng of 5-HT(3A) cRNA, respectively. In radioligand binding studies on membrane preparations of oocytes expressing 5-HT(3A) receptors, THC did not alter the specific binding of a 5-HT(3A) receptor antagonist, [(3)H]GR65630. In the presence of 1 μM THC, the maximum 5-HT-induced response was also inhibited without a significant change in 5-HT potency, indicating that THC acts as a noncompetitive antagonist on 5-HT(3) receptors. In adult rat nodose ganglion neurons, application of 1 μM THC caused a significant inhibition of 5-HT(3) receptors, extent of which correlated with the density of 5-HT-induced currents, indicating that the observed THC effects occur in mammalian neurons. The inhibition of 5-HT(3) receptors by THC may contribute to its pharmacological actions in nociception and emesis.
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Affiliation(s)
- K H S Yang
- Department of Biological Sciences, Schmid College of Science, Chapman University, One University Drive, Orange, CA 92866, USA
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Yang KH, Galadari S, Isaev D, Petroianu G, Shippenberg TS, Oz M. The nonpsychoactive cannabinoid cannabidiol inhibits 5-hydroxytryptamine3A receptor-mediated currents in Xenopus laevis oocytes. J Pharmacol Exp Ther 2010; 333:547-54. [PMID: 20160007 DOI: 10.1124/jpet.109.162594] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
The effect of the plant-derived nonpsychotropic cannabinoid, cannabidiol (CBD), on the function of hydroxytryptamine (5-HT)3A receptors expressed in Xenopus laevis oocytes was investigated using two-electrode voltage-clamp techniques. CBD reversibly inhibited 5-HT (1 microM)-evoked currents in a concentration-dependent manner (IC50 = 0.6 microM). CBD (1 microM) did not alter specific binding of the 5-HT3A antagonist [3H]3-(5-methyl-1H-imidazol-4-yl)-1-(1-methylindol-3-yl)propan-1-one (GR65630), in oocytes expressing 5-HT3A receptors. In the presence of 1 microM CBD, the maximal 5-HT-induced currents were also inhibited. The EC50 values were 1.2 and 1.4 microM, in the absence and presence of CBD, indicating that CBD acts as a noncompetitive antagonist of 5-HT3 receptors. Neither intracellular BAPTA injection nor pertussis toxin pretreatment (5 microg/ml) altered the CBD-evoked inhibition of 5-HT-induced currents. CBD inhibition was inversely correlated with 5-HT3A expression levels and mean 5-HT3 receptor current density. Pretreatment with actinomycin D, which inhibits protein transcription, decreased the mean 5-HT3 receptor current density and increased the magnitude of CBD inhibition. These data demonstrate that CBD is an allosteric inhibitor of 5-HT3 receptors expressed in X. laevis oocytes. They further suggest that allosteric inhibition of 5-HT3 receptors by CBD may contribute to its physiological roles in the modulation of nociception and emesis.
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Affiliation(s)
- Keun-Hang Yang
- Department of Biological Sciences, Schmid College of Science, Chapman University, Orange, California, USA
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Backhouse N, Delporte C, Apablaza C, Farías M, Goïty L, Arrau S, Negrete R, Castro C, Miranda H. Antinociceptive activity of Buddleja globosa (matico) in several models of pain. JOURNAL OF ETHNOPHARMACOLOGY 2008; 119:160-165. [PMID: 18639621 DOI: 10.1016/j.jep.2008.06.022] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2008] [Revised: 06/16/2008] [Accepted: 06/19/2008] [Indexed: 05/26/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Leaf extracts of Buddleja globosa (Buddlejaceae) are used in Chilean folk medicine for wound healing. The anti-inflammatory (topic and per os), analgesic (per os) effects and the antioxidant activity of Buddleja globosa were for the first time reported by us. AIM OF THE STUDY Assess the antinociceptive activity of the methanol sequential and global extracts using complementary chemical and thermal models of pain, characterize pharmacologically the antinociception induced, evaluate seasonal influence to support Buddleja globosa medicinal use. MATERIALS AND METHODS Global methanol, sequential methanol and ethanol (leaves collected in autumn and summer) extracts were evaluated for oral and topic analgesia in tail flick, formalin and writhing models, verbascoside and 7-O-luteolin glucoside were assayed in tail flick and writhing. Ibuprofen was used as reference. For characterization of induced antinociception, naltrexone, naltrindole, tropisetron, nor-binaltorphimine, prazosin, yohimbine, atropine, and N-nitro-l-arginine methyl ester were used as antagonists and inhibitors drugs. RESULTS Seasonal influence was observed since autumn extract resulted less active. Extracts showed a dose-dependent antinociceptive activity in all assays, the highest effects were obtained for the formalin and writhing test. Verbascoside was more active than ibuprofen in the writhing test (67.6% and 50.0% at equimolar doses) and showed similar effects in the tail flick (topic and oral) near 25% at equivalent doses - ED25 or EC25 - to ibuprofen. Luteolin 7-O-glucoside was slightly more active in the tail flick test and nearly half active than verbascoside in the writhing assay. Effectiveness was higher for the sequential than for global alcoholic extracts, and can be increased by selective blocking of opioid receptors. Global methanol extract seems modulated only by naltrexone. CONCLUSIONS Analgesic effect of Buddleja globosa is here demonstrated validating its use in traditional medicine. Season influence is important to be considered.
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Affiliation(s)
- Nadine Backhouse
- Laboratory of Natural Products, Department of Pharmacological and Toxicological Chemistry, Faculty of Chemical and Pharmaceutical Sciences, University of Chile, Casilla 233, Santiago 1, Chile.
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Mowafi HA, Arab SA, Ismail SA, Al-Ghamdi A. The Effects of Intravenous Granisetron on the Sensory and Motor Blockade Produced by Intrathecal Bupivacaine. Anesth Analg 2008; 106:1322-5, table of contents. [DOI: 10.1213/ane.0b013e318165e012] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Christidis N, Nilsson A, Kopp S, Ernberg M. Intramuscular Injection of Granisetron Into the Masseter Muscle Increases the Pressure Pain Threshold in Healthy Participants and Patients With Localized Myalgia. Clin J Pain 2007; 23:467-72. [PMID: 17575485 DOI: 10.1097/ajp.0b013e318058abb1] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVES The aims of this study were to experimentally investigate whether an intramuscular injection of the 5-HT(3) antagonist granisetron into the masseter muscle increases the mechanical pain threshold in healthy participants and reduces masseter muscle pain or allodynia in patients with craniofacial myalgia. METHODS Eighteen patients with bilateral localized myalgia of the masseter muscle and 24 healthy participants participated in this randomized, double-blind study, in which granisetron was injected on one side and isotonic saline on the other side. Pain (Visual Analog Scale) and pressure pain threshold (PPT) were recorded before and during 30 minutes after injections and the changes from baseline were analyzed with analysis of variance. RESULTS In both groups, the PPT increased after injection of granisetron whereas it decreased after saline. The difference between substances was significant (patients: P=0.016; healthy participants: P=0.029). In the healthy participants there was also a significant time effect (P<0.001) and an interaction between time and substance (P=0.022). The post-hoc test showed that the difference between substances was significant 0 to 15 minutes after injections (Bonferroni t test; P<0.05). The pain intensity from the masseter muscle did not differ between substances, but there was a significant time effect (P<0.001) and an interaction between time and substance (P<0.001). The post-hoc test showed significantly lower pain intensity on the granisetron side 0 to 2 minutes after injections (Bonferroni t test; P<0.05). CONCLUSIONS This study indicates that intramuscular injection of granisetron into the masseter muscle increases the PPT in healthy participants and in patients with craniofacial myalgia.
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Affiliation(s)
- Nikolaos Christidis
- Department of Clinical Oral Physiology, Institute of Odontology, Karolinska Institutet, Huddinge, Sweden.
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Müller W, Fiebich BL, Stratz T. [5-HT3 receptor antagonist als analgetics in rheumatic diseases]. Z Rheumatol 2007; 65:546, 548-52. [PMID: 16450149 DOI: 10.1007/s00393-005-0014-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2005] [Accepted: 07/25/2005] [Indexed: 12/01/2022]
Abstract
Various rheumatic diseases like fibromyalgia, systemic inflammatory rheumatic disorders and localized diseases, such as arthritides and activated arthroses, tendinopathies and periarthropathies, as well as trigger points can be improved considerably by treatment with the 5-HT3 receptor antagonist tropisetron. Particularly in the latter group of diseases, local injections have done surprisingly rapid analgesic action. This effect matches that of local anesthetics, but lasts considerably longer and is comparable to local injections of local anesthetics combined with corticosteroids. The action of the 5-HT3 receptor antagonists can be attributed to an antinociceptive effect that occurs at the same time as an antiphlogistic and probably also an immunosuppressive effect. Whereas an inhibited release of substance P from the nociceptors, and possibly some other neurokins as well, seems to be the most likely explanation for the antinociceptive action, the antiphlogistic effect is primarily due to an inhibited formation of various different phlogistic substances; in some conditions, like systemic inflammatory rheumatic diseases, for example, the 5-HT3 receptor antagonists may exert an immunosuppressive effect in addition to this.
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Affiliation(s)
- W Müller
- Hochrhein-Institut für Rehabilitationsforschung, Bad Säckingen.
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Abstract
The 5-HT3 receptor is a neurotransmitter-gated ion channel. It is a member of the Cys-loop family of receptors, which also includes nicotinic acetylcholine, glycine and GABAA receptors. Each member of the family consists of an arrangement of five subunits surrounding a central ion-conducting pore. The 5-HT3 receptor binding site is composed of six loops from two adjacent subunits, and the critical ligand binding residues within these loops are well documented. There are a range of 5-HT3 receptor agonists and competitive antagonists, but it is the antagonists that dominate their clinical use. Studies have proposed a range of disease symptoms that might be amenable to 5-HT3 receptor selective compounds; however, so far only the treatment of emesis and irritable bowel syndrome have been fully realised. In this review, the authors look at the structure, function and distribution of 5-HT3 receptors and how this may influence their role in disease. The authors also describe the existing clinical applications of 5-HT3 antagonists and the future potential of these drugs.
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Affiliation(s)
- Andrew J Thompson
- University of Cambridge, Department of Biochemistry, Tennis Court Road, Cambridge , CB2 1QW, UK
| | - Sarah CR Lummis
- University of Cambridge, Department of Biochemistry, Tennis Court Road, Cambridge , CB2 1QW, UK
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Rex A, Bert B, Fink H. [History and new developments. The pharmacology of 5-ht3 antagonists]. PHARMAZIE IN UNSERER ZEIT 2007; 36:342-53. [PMID: 17722161 DOI: 10.1002/pauz.200700230] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Affiliation(s)
- André Rex
- Institut für Pharmakologie und Toxikologie an der Charité Berlin
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Carrillo-de-la-Peña MT, Vallet M, Pérez MI, Gómez-Perretta C. Intensity dependence of auditory-evoked cortical potentials in fibromyalgia patients: a test of the generalized hypervigilance hypothesis. THE JOURNAL OF PAIN 2006; 7:480-7. [PMID: 16814687 DOI: 10.1016/j.jpain.2006.01.452] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2005] [Revised: 12/23/2005] [Accepted: 01/26/2006] [Indexed: 12/30/2022]
Abstract
UNLABELLED On the basis of recent evidence concerning the amplification of incoming stimulation in fibromyalgia (FM) patients, it has been proposed that a generalized hypervigilance of painful and nonpainful sensations may be at the root of this disorder. So far, research into this issue has been inconclusive, possibly owing to the lack of agreement as to the operational definition of "generalized hypervigilance" and to the lack of robust objective measures characterizing the sensory style of FM patients. In this study, we recorded auditory-evoked potentials (AEPs) elicited by tones of increasing intensity (60, 70, 80, 90, and 105 dB) in 27 female FM patients and 25 healthy controls. Fibromyalgia patients presented shorter N1 and P2 latencies and a stronger intensity dependence of their AEPs. Both results suggest that FM patients may be hypervigilant to sensory stimuli, especially when very loud tones are used. The most noteworthy difference between patients and control subjects is at the highest stimulus intensity, for which far more patients maintained increased N1-P2 amplitudes in relation to the 90-dB tones. The larger AEP amplitudes to the 105-dB tones suggest that defects in an inhibitory system protecting against overstimulation may be a crucial factor in the pathophysiology of FM. Because a stronger loudness dependence of AEPs has been related to weak serotonergic transmission, it is hypothesized that for many FM patients deficient inhibition of the response to noxious and intense auditory stimuli may be due to a serotonergic deficit. PERSPECTIVE The study of auditory-evoked potentials in response to tones of increasing intensity in FM patients may help to clarify the pathophysiology of this disorder, especially regarding the role of inhibition deficits involving serotonergic dysfunction, and may be a useful tool to guide the pharmacologic treatment of FM patients.
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Affiliation(s)
- M T Carrillo-de-la-Peña
- Departamento de Psicología Clínica y Psicobiología, Universidad de Santiago de Compostela, Santiago de Compostela, Spain.
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Dukat M, Wesołowska A. Antinociception: Mechanistic studies on the action of MD-354 and clonidine. Part 1. The 5-HT3 component. Eur J Pharmacol 2005; 528:59-64. [PMID: 16321376 DOI: 10.1016/j.ejphar.2005.10.037] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2005] [Revised: 10/18/2005] [Accepted: 10/25/2005] [Indexed: 11/24/2022]
Abstract
MD-354 (m-chlorophenylguanidine) is a 5-HT3/alpha2B-adrenoceptor ligand. Both receptors play a role in antinociception. In the mouse tail-flick assay, subcutaneously administered MD-354 was inactive as an analgesic. However, a combination of an inactive dose of clonidine (0.25 mg/kg) with an inactive dose of MD-354 (6 mg/kg) produced a substantial antinociceptive effect (maximal possible effect=66%). Considering the 5-HT3 receptor partial agonist properties of MD-354, the analgesia enhancing effect of MD-354 on clonidine might be associated, at least in part, with its 5-HT3 receptor agonist or antagonist activity. Combinations of an inactive dose of clonidine (0.25 mg/kg) with 5-HT3 receptor antagonists (tropisetron, zacopride and ondansetron) were examined. Saline-like doses of tropisetron, zacopride and ondansetron significantly enhanced the antinociceptive effect of clonidine (combinations: maximal possible effect=86%, 82% and 79% respectively), suggesting that MD-354 may enhance the analgesic actions of clonidine, at least in part, through a 5-HT3 receptor antagonist mechanism.
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Affiliation(s)
- Magorzata Dukat
- Department of Medicinal Chemistry, School of Pharmacy, Box 980540 Virginia Commonwealth University, Richmond, VA 23298-0540, USA.
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