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Hoshijima H, Hunt M, Nagasaka H, Yaksh T. Systematic Review of Systemic and Neuraxial Effects of Acetaminophen in Preclinical Models of Nociceptive Processing. J Pain Res 2021; 14:3521-3552. [PMID: 34795520 PMCID: PMC8594782 DOI: 10.2147/jpr.s308028] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Accepted: 09/11/2021] [Indexed: 12/29/2022] Open
Abstract
Acetaminophen (APAP) in humans has robust effects with a high therapeutic index in altering postoperative and inflammatory pain states in clinical and experimental pain paradigms with no known abuse potential. This review considers the literature reflecting the preclinical actions of acetaminophen in a variety of pain models. Significant observations arising from this review are as follows: 1) acetaminophen has little effect upon acute nociceptive thresholds; 2) acetaminophen robustly reduces facilitated states as generated by mechanical and thermal hyperalgesic end points in mouse and rat models of carrageenan and complete Freund’s adjuvant evoked inflammation; 3) an antihyperalgesic effect is observed in models of facilitated processing with minimal inflammation (eg, phase II intraplantar formalin); and 4) potent anti-hyperpathic effects on the thermal hyperalgesia, mechanical and cold allodynia, allodynic thresholds in rat and mouse models of polyneuropathy and mononeuropathies and bone cancer pain. These results reflect a surprisingly robust drug effect upon a variety of facilitated states that clearly translate into a wide range of efficacy in preclinical models and to important end points in human therapy. The specific systems upon which acetaminophen may act based on targeted delivery suggest both a spinal and a supraspinal action. Review of current targets for this molecule excludes a role of cyclooxygenase inhibitor but includes effects that may be mediated through metabolites acting on the TRPV1 channel, or by effect upon cannabinoid and serotonin signaling. These findings suggest that the mode of action of acetaminophen, a drug with a long therapeutic history of utilization, has surprisingly robust effects on a variety of pain states in clinical patients and in preclinical models with a good therapeutic index, but in spite of its extensive use, its mechanisms of action are yet poorly understood.
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Affiliation(s)
- Hiroshi Hoshijima
- Department of Anesthesiology, Saitama Medical University Hospital, Saitama, Japan
| | - Matthew Hunt
- Departments of Anesthesiology and Pharmacology, University of California, San Diego Anesthesia Research Laboratory, La Jolla, CA, USA
| | - Hiroshi Nagasaka
- Department of Anesthesiology, Saitama Medical University Hospital, Saitama, Japan
| | - Tony Yaksh
- Departments of Anesthesiology and Pharmacology, University of California, San Diego Anesthesia Research Laboratory, La Jolla, CA, USA
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Giacomini ACVV, Scolari N, Marcon L, Bueno BW, Dos Santos BE, Demin KA, Kalueff AV, de Abreu MS. Putative anxiolytic-like behavioral effects of acute paracetamol in adult zebrafish. Behav Brain Res 2021; 409:113293. [PMID: 33838148 DOI: 10.1016/j.bbr.2021.113293] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2021] [Revised: 03/14/2021] [Accepted: 04/01/2021] [Indexed: 11/29/2022]
Abstract
Typically triggered by stress, anxiety disorders are most common and widespread mental illnesses. The zebrafish (Danio rerio) is rapidly becoming an important aquatic model species in stress research and central nervous system (CNS) drug screening. Paracetamol is currently the most prescribed medication for pain and fever, and is among the most used drugs globally. However, its CNS effects, especially on anxiety, in both clinical and animal studies remain poorly understood. Capitalizing on zebrafish as a powerful model system, here we evaluate the effects of paracetamol on anxiety-like behavior in adult fish, and its changes following an acute stress exposure. Overall, we report an anxiolytic-like profile of acute paracetamol treatment, and its alleviation of stress-evoked anxiety, in adult short-fin wild type zebrafish. Collectively, these findings suggest complex neuroactive effects of paracetamol, and reinforce the growing importance of zebrafish models for drug screening, including the search for novel putative anti-stress therapies.
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Affiliation(s)
- Ana C V V Giacomini
- Bioscience Institute, University of Passo Fundo (UPF), Passo Fundo, RS, Brazil; University of Passo Fundo (UPF), Passo Fundo, RS, Brazil
| | - Naiara Scolari
- Bioscience Institute, University of Passo Fundo (UPF), Passo Fundo, RS, Brazil
| | - Leticia Marcon
- Bioscience Institute, University of Passo Fundo (UPF), Passo Fundo, RS, Brazil
| | - Barbara W Bueno
- Bioscience Institute, University of Passo Fundo (UPF), Passo Fundo, RS, Brazil
| | - Bruna E Dos Santos
- Bioscience Institute, University of Passo Fundo (UPF), Passo Fundo, RS, Brazil
| | - Konstantin A Demin
- Institute of Experimental Medicine, Almazov National Medcial Research Center, Ministry of Healthcare of Russian Federation, St. Petersburg, Russia; Institute of Translational Biomedicine, St. Petersburg State University, St. Petersburg, Russia; Granov Scientific Research Center for Radiology and Surgical Technologies, Ministry of Healthcare of Russian Federation, St. Petersburg, Russia; Neuroscience Program, Sirius University, Sochi, Russia; Scientific Research Institute of Neurosciences and Medicine, Novosibirsk, Russia
| | - Allan V Kalueff
- School of Pharmacy, Southwest University, Chongqing, China; Ural Federal University, Ekaterinburg, Russia; Granov Scientific Research Center for Radiology and Surgical Technologies, Ministry of Healthcare of Russian Federation, St. Petersburg, Russia.
| | - Murilo S de Abreu
- Bioscience Institute, University of Passo Fundo (UPF), Passo Fundo, RS, Brazil; Laboratory of Cell and Molecular Biology and Neurobiology, Moscow Institute of Physics and Technology, Moscow, Russia; The International Zebrafish Neuroscience Research Consortium (ZNRC), Slidell, LA, USA.
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3
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Bernstein J, Spitzer Y, Ohaegbulam K, Reddy S, Song J, Romanelli E, Nair S. The analgesic efficacy of IV acetaminophen for acute postoperative pain in C-section patients: a randomized, double-blind, placebo-controlled study. J Matern Fetal Neonatal Med 2020; 35:933-940. [PMID: 32156175 DOI: 10.1080/14767058.2020.1735337] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Background: The rate of cesarean delivery is on the rise in the USA. Satisfactory postoperative analgesia remains a top priority for cesarean delivery. Multimodal analgesia with a reduction in opioid consumption and improvement in patient satisfaction is a goal for anesthesiologists caring for this patient population. Our study sought to assess whether IV acetaminophen in four divided doses over 24 h decreased pain scores and opioid requirements in patients undergoing cesarean delivery with neuraxial anesthesia.Methods: 66 patients undergoing elective cesarean delivery under spinal anesthesia with hyperbaric bupivacaine 12 mg, fentanyl 10 µg, and preservative-free morphine 150 µg were randomized to receive either IV acetaminophen or IV placebo for four consecutive doses in the first 24 h postoperatively. The need for rescue medication using morphine equivalence, pain scores, patient satisfaction, and side effects were assessed by a blinded researcher in the first 24 and 48 h postoperatively.Results: There was no difference in opioid requirements in the acetaminophen versus placebo group, 44.32 ± 23 mg versus 47.59 ± 28 mg (p = .607), respectively at 24 h. There was also no difference at 48 h, 57.95 ± 20 mg versus 56.59 ± 22 mg (p = .795). Postoperative pain scores, patient satisfaction, and adverse events were similar in both groups as well.Conclusions: The results of this study failed to demonstrate any additional benefits of administering multiple doses of IV acetaminophen for treating postoperative pain in patients who have undergone CS surgery and receiving intra-thecal morphine as part of their anesthesia and analgesia.Trial Registry number: NCT02069184.
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Affiliation(s)
- Jeffrey Bernstein
- Department of Anesthesiology, Montefiore Hospital and Medical Center, New York, NY, USA
| | - Yelena Spitzer
- Department of Anesthesiology, Montefiore Hospital and Medical Center, New York, NY, USA
| | | | - Shamantha Reddy
- Department of Anesthesiology, Montefiore Hospital and Medical Center, New York, NY, USA
| | - Jing Song
- Department of Anesthesiology, Montefiore Hospital and Medical Center, New York, NY, USA
| | - Erik Romanelli
- Department of Anesthesiology, Montefiore Hospital and Medical Center, New York, NY, USA
| | - Singh Nair
- Department of Anesthesiology, Montefiore Hospital and Medical Center, New York, NY, USA
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Shimodaira T, Mikoshiba S, Taguchi T. Nonsteroidal anti-inflammatory drugs and acetaminophen ameliorate muscular mechanical hyperalgesia developed after lengthening contractions via cyclooxygenase-2 independent mechanisms in rats. PLoS One 2019; 14:e0224809. [PMID: 31693705 PMCID: PMC6834261 DOI: 10.1371/journal.pone.0224809] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Accepted: 10/22/2019] [Indexed: 01/04/2023] Open
Abstract
Nonsteroidal anti-inflammatory drugs and acetaminophen are cyclooxygenase inhibitors commonly used as symptomatic medicines for myofascial pain syndrome. Using the selective inhibitors celecoxib and zaltoprofen, cyclooxygenase-2 has been shown to be involved in the initiation, but not the maintenance, of muscular mechanical hyperalgesia induced by lengthening contractions, which serves as a useful model for the study of myofascial pain syndrome. The effect of other cyclooxygenase-2 inhibitors, such as acetylsalicylic acid, ibuprofen, loxoprofen sodium, and acetaminophen, on muscular mechanical hyperalgesia during maintenance has not been studied. Here, we examined the analgesic effects of the nonsteroidal anti-inflammatory drugs and acetaminophen on the model. Consistent with previous studies, mechanical withdrawal threshold of the muscle was significantly decreased and reached its lowest level 24 h after lengthening contractions. Celecoxib had no effect on muscular mechanical hyperalgesia, when orally administered 24 h after lengthening contractions. In contrast, acetylsalicylic acid, ibuprofen, loxoprofen sodium, and acetaminophen increased the withdrawal threshold, which had decreased by lengthening contractions, in a dose-dependent manner. These results demonstrate the analgesic actions of nonsteroidal anti-inflammatory drugs and acetaminophen in the maintenance process of lengthening contraction-induced muscular mechanical hyperalgesia, which may occur through cyclooxygenase-2 independent mechanisms.
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Affiliation(s)
| | - Shigeo Mikoshiba
- Pharmaceutical Research Laboratories, Lion Corporation, Odawara, Japan
| | - Toru Taguchi
- Department of Physical Therapy, Niigata University of Health and Welfare, Kita-ku, Niigata, Japan
- Institute for Human Movement and Medical Sciences, Niigata University of Health and Welfare, Kita-ku, Niigata, Japan
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Kandis S, Ates M, Kizildag S, Camsari GB, Yuce Z, Guvendi G, Koc B, Karakilic A, Camsari UM, Uysal N. Acetaminophen (paracetamol) affects empathy-like behavior in rats: Dose-response relationship. Pharmacol Biochem Behav 2018; 175:146-151. [DOI: 10.1016/j.pbb.2018.10.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/28/2018] [Revised: 10/20/2018] [Accepted: 10/20/2018] [Indexed: 10/28/2022]
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Involvement of 5-HT 1A/1B receptors in the antinociceptive effect of paracetamol in the rat formalin test. NEUROBIOLOGY OF PAIN 2018; 3:15-21. [PMID: 31194055 PMCID: PMC6550097 DOI: 10.1016/j.ynpai.2018.01.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Revised: 01/28/2018] [Accepted: 01/29/2018] [Indexed: 12/16/2022]
Abstract
The mechanism of analgesic action of paracetamol (acetominophen) remains still unknown. However, a relationship between serotonergic system and the effect of paracetamol has been previously demonstrated. The serotonin activity in the brainstem is primarily under the control of 5-HT1A somatodendritic receptors, although some data also suggest the involvement of 5-HT1B receptors. To determine whether the 5-HT1A and 5-HT1B receptors are involved in the antinociceptive effect of paracetamol, we evaluated the effect of paracetamol (0.125-1 g/kg i.p.) followed by different antagonists [WAY 100,635 (0.8 mg/kg s.c.) and SB 216,641 (0.8 mg/kg s.c.)] or agonists [8-OH-DPAT (0.125 mg/kg s.c.) and CP 93,129 (0.125 mg/kg s.c.)] of 5-HT1A and 5-HT1B receptors, respectively, in the rat model of formalin-induced pain. We demonstrated that paracetamol administration showed a dose-dependent antinociceptive effect in the formalin test. WAY 100,635 (5-HT1A antagonist) induced an increase in the antinociceptive effect of paracetamol at 250 mg/kg doses. Conversely, 8-OH-DPAT (5-HT1A agonist) decreased the antinociceptive effect of paracetamol at 500-1000 mg/kg doses. However, SB216641 (5-HT1B antagonist) modified weakly the antinociceptive effect of paracetamol at 250 mg/kg doses and CP 93,129 (5-HT1B agonist) not produce a clear effect in the antinociceptive effect of paracetamol. These results suggest that the antinociceptive effect of paracetamol can be enhanced mainly by compounds having 5-HT1A antagonist properties in the formalin test and maybe by 5-HT1B receptors antagonists.
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Li Q, Zhuang Q, Gu Y, Dai C, Gao X, Wang X, Wen H, Li X, Zhang Y. Enhanced analgesic effects of nefopam in combination with acetaminophen in rodents. Biomed Rep 2017; 8:176-183. [DOI: 10.3892/br.2017.1032] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Accepted: 12/12/2017] [Indexed: 11/06/2022] Open
Affiliation(s)
- Qian Li
- Department of Pharmacology, School of Life Science and Biopharmaceutics, Shenyang Pharmaceutical University, Shenyang, Liaoning 110016, P.R. China
| | - Quankun Zhuang
- Department of Pharmacology, School of Life Science and Biopharmaceutics, Shenyang Pharmaceutical University, Shenyang, Liaoning 110016, P.R. China
| | - Yaru Gu
- Department of Pharmacology, School of Life Science and Biopharmaceutics, Shenyang Pharmaceutical University, Shenyang, Liaoning 110016, P.R. China
| | - Cailing Dai
- Department of Pharmacology, School of Life Science and Biopharmaceutics, Shenyang Pharmaceutical University, Shenyang, Liaoning 110016, P.R. China
| | - Xiaoxiao Gao
- Department of Pharmacology, School of Life Science and Biopharmaceutics, Shenyang Pharmaceutical University, Shenyang, Liaoning 110016, P.R. China
| | - Xiaomin Wang
- Department of Pharmacology, School of Life Science and Biopharmaceutics, Shenyang Pharmaceutical University, Shenyang, Liaoning 110016, P.R. China
| | - Huimin Wen
- Department of Pharmacology, School of Life Science and Biopharmaceutics, Shenyang Pharmaceutical University, Shenyang, Liaoning 110016, P.R. China
| | - Xin Li
- Department of Pharmacology, School of Life Science and Biopharmaceutics, Shenyang Pharmaceutical University, Shenyang, Liaoning 110016, P.R. China
| | - Yuyang Zhang
- Department of Pharmacology, School of Life Science and Biopharmaceutics, Shenyang Pharmaceutical University, Shenyang, Liaoning 110016, P.R. China
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Blecharz-Klin K, Piechal A, Jawna-Zboińska K, Pyrzanowska J, Wawer A, Joniec-Maciejak I, Widy-Tyszkiewicz E. Paracetamol − Effect of early exposure on neurotransmission, spatial memory and motor performance in rats. Behav Brain Res 2017; 323:162-171. [DOI: 10.1016/j.bbr.2017.01.051] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Revised: 01/30/2017] [Accepted: 01/30/2017] [Indexed: 02/02/2023]
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Pickering G, Macian N, Dubray C, Pereira B. Paracetamol sharpens reflection and spatial memory: a double-blind randomized controlled study in healthy volunteers. DRUG DESIGN DEVELOPMENT AND THERAPY 2016; 10:3969-3976. [PMID: 27980393 PMCID: PMC5147402 DOI: 10.2147/dddt.s111590] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Background Acetaminophen (APAP, paracetamol) mechanism for analgesic and antipyretic outcomes has been largely addressed, but APAP action on cognitive function has not been studied in humans. Animal studies have suggested an improved cognitive performance but the link with analgesic and antipyretic modes of action is incomplete. This study aims at exploring cognitive tests in healthy volunteers in the context of antinociception and temperature regulation. A double-blind randomized controlled study (NCT01390467) was carried out from May 30, 2011 to July 12, 2011. Methods Forty healthy volunteers were included and analyzed. Nociceptive thresholds, core temperature (body temperature), and a battery of cognitive tests were recorded before and after oral APAP (2 g) or placebo: Information sampling task for predecisional processing, Stockings of Cambridge for spatial memory, reaction time, delayed matching of sample, and pattern recognition memory tests. Analysis of variance for repeated measures adapted to crossover design was performed and a two-tailed type I error was fixed at 5%. Results APAP improved information sampling task (diminution of the number of errors, latency to open boxes, and increased number of opened boxes; all P<0.05). Spatial planning and working memory initial thinking time were decreased (P=0.04). All other tests were not modified by APAP. APAP had an antinociceptive effect (P<0.01) and body temperature did not change. Conclusion This study shows for the first time that APAP sharpens decision making and planning strategy in healthy volunteers and that cognitive performance and antinociception are independent of APAP effect on thermogenesis. We suggest that cognitive performance mirrors the analgesic rather than thermic cascade of events, with possibly a central role for serotonergic and cannabinoid systems that need to be explored further in the context of pain and cognition.
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Affiliation(s)
- Gisèle Pickering
- University Hospital, CHU Clermont-Ferrand, Centre de Pharmacologie Clinique; Inserm, CIC 1405, UMR Neurodol 1107; Clermont Université, Laboratoire de Pharmacologie, Faculté de médicine
| | - Nicolas Macian
- University Hospital, CHU Clermont-Ferrand, Centre de Pharmacologie Clinique; Inserm, CIC 1405, UMR Neurodol 1107
| | - Claude Dubray
- University Hospital, CHU Clermont-Ferrand, Centre de Pharmacologie Clinique; Inserm, CIC 1405, UMR Neurodol 1107; Clermont Université, Laboratoire de Pharmacologie, Faculté de médicine
| | - Bruno Pereira
- CHU de Clermont-Ferrand, Délégation Recherche Clinique Innovation, Clermont-Ferrand, France
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Blecharz-Klin K, Joniec-Maciejak I, Jawna K, Pyrzanowska J, Piechal A, Wawer A, Widy-Tyszkiewicz E. Developmental exposure to paracetamol causes biochemical alterations in medulla oblongata. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2015; 40:369-374. [PMID: 26233562 DOI: 10.1016/j.etap.2015.07.001] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Revised: 07/02/2015] [Accepted: 07/03/2015] [Indexed: 06/04/2023]
Abstract
The effect and safety of prenatal and early life administration of paracetamol - routinely used over-the-counter antipyretic and analgesic medication on monoamines content and balance of amino acids in the medulla oblongata is still unknown. In this study we have determined the level of neurotransmitters in this structure in two-month old Wistar male rats exposed to paracetamol in the dose of 5 (P5, n=10) or 15mg/kg b.w. (P15, n=10) during prenatal period, lactation and till the end of the second month of life. Control group received drinking water (Con, n=10). Monoamines, their metabolites and amino acids concentration in medulla oblongata of rats were determined using high performance liquid chromatography (HPLC) in 60 postnatal day (PND60). This experiment shows that prenatal and early life paracetamol exposure modulates neurotransmission associated with serotonergic, noradrenergic and dopaminergic system in medulla oblongata. Reduction of alanine and taurine levels has also been established.
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Affiliation(s)
- Kamilla Blecharz-Klin
- Department of Experimental and Clinical Pharmacology, Medical University of Warsaw, Centre for Preclinical Research and Technology CePT, Banacha 1B, 02-097 Warsaw, Poland
| | - Ilona Joniec-Maciejak
- Department of Experimental and Clinical Pharmacology, Medical University of Warsaw, Centre for Preclinical Research and Technology CePT, Banacha 1B, 02-097 Warsaw, Poland
| | - Katarzyna Jawna
- Department of Experimental and Clinical Pharmacology, Medical University of Warsaw, Centre for Preclinical Research and Technology CePT, Banacha 1B, 02-097 Warsaw, Poland
| | - Justyna Pyrzanowska
- Department of Experimental and Clinical Pharmacology, Medical University of Warsaw, Centre for Preclinical Research and Technology CePT, Banacha 1B, 02-097 Warsaw, Poland
| | - Agnieszka Piechal
- Department of Experimental and Clinical Pharmacology, Medical University of Warsaw, Centre for Preclinical Research and Technology CePT, Banacha 1B, 02-097 Warsaw, Poland
| | - Adriana Wawer
- Department of Experimental and Clinical Pharmacology, Medical University of Warsaw, Centre for Preclinical Research and Technology CePT, Banacha 1B, 02-097 Warsaw, Poland
| | - Ewa Widy-Tyszkiewicz
- Department of Experimental and Clinical Pharmacology, Medical University of Warsaw, Centre for Preclinical Research and Technology CePT, Banacha 1B, 02-097 Warsaw, Poland.
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Yisarakun W, Chantong C, Supornsilpchai W, Thongtan T, Srikiatkhachorn A, Reuangwechvorachai P, Maneesri-le Grand S. Up-regulation of calcitonin gene-related peptide in trigeminal ganglion following chronic exposure to paracetamol in a CSD migraine animal model. Neuropeptides 2015; 51:9-16. [PMID: 25998753 DOI: 10.1016/j.npep.2015.03.008] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Revised: 03/02/2015] [Accepted: 03/30/2015] [Indexed: 12/24/2022]
Abstract
Previously, our group has demonstrated that chronic paracetamol (APAP) treatment induces alterations to the trigeminovascular nociceptive system in the cortical spreading depression (CSD) migraine animal model. The calcitonin gene related peptide (CGRP) is a key neuropeptide involved in the activation of the trigeminovascular nociceptive system. Therefore, this study examined the expression levels of CGRP in the trigeminal ganglion (TG) after chronic APAP exposure (0, 15, and 30 days) using a CSD model. Rats were divided into control, CSD only, APAP only and APAP treatment with CSD groups. A single injection (i.p.) of APAP (200 mg/kg body weight) was given to the 0-day APAP-treated groups, while the other APAP-treated groups received daily injections for 15 and 30 days. CSD was induced by the topical application of KCl to the parietal cortex. The protein expression of CGRP in the TG was evaluated by immunohistochemistry, and the CGRP mRNA level was investigated by real-time quantitative reverse transcription polymerase chain reaction. The results revealed that the induction of CSD significantly increased the level of CGRP protein but had no effect on CGRP mRNA level. Pretreatment with APAP 1 hour before CSD activation significantly reduced CGRP expression induced by CSD. In contrast, chronic treatment with APAP (15 and 30 days) significantly enhanced CGRP expression in both protein and mRNA levels when compared with the control groups. In combination with CSD, the expression of CGRP further increased in the animal with 30 day treatment. These findings indicate that chronic treatment with APAP induces an increase of CGRP expression in the TG. This alteration may be associated with the increased trigeminovascular nociception observed in our previous studies.
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Affiliation(s)
- Waranurin Yisarakun
- Department of Pathology, Faculty of Medicine, Chulalongkorn University, Bangkok 10330, Thailand
| | - Chattraporn Chantong
- Department of Pathology, Faculty of Medicine, Chulalongkorn University, Bangkok 10330, Thailand
| | - Weera Supornsilpchai
- Department of Physiology, Faculty of Dentistry, Chulalongkorn University, Bangkok 10330, Thailand
| | - Thananya Thongtan
- Department of Biochemistry, Faculty of Medicine, Chulalongkorn University, Bangkok 10330, Thailand
| | - Anan Srikiatkhachorn
- Department of Physiology, Faculty of Medicine, Chulalongkorn University, Bangkok 10330, Thailand
| | | | - Supang Maneesri-le Grand
- Department of Pathology, Faculty of Medicine, Chulalongkorn University, Bangkok 10330, Thailand.
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Messerer B, Grögl G, Stromer W, Jaksch W. [Pediatric perioperative systemic pain therapy: Austrian interdisciplinary recommendations on pediatric perioperative pain management]. Schmerz 2015; 28:43-64. [PMID: 24550026 DOI: 10.1007/s00482-013-1384-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
BACKGROUND Many analgesics used in adult medicine are not licensed for pediatric use. Licensing limitations do not, however, justify that children are deprived of a sufficient pain therapy particularly in perioperative pain therapy. The treatment is principally oriented to the strength of the pain. Due to the degree of pain caused, intramuscular and subcutaneous injections should be avoided generally. NON-OPIOIDS The basis of systemic pain therapy for children are non-opioids and primarily non-steroidal anti-inflammatory drugs (NSAIDs). They should be used prophylactically. The NSAIDs are clearly more effective than paracetamol for acute posttraumatic and postoperative pain and additionally allow economization of opioids. Severe side effects are rare in children but administration should be carefully considered especially in cases of hepatic and renal dysfunction or coagulation disorders. Paracetamol should only be taken in pregnancy and by children when there are appropriate indications because a possible causal connection with bronchial asthma exists. To ensure a safe dosing the age, body weight, duration of therapy, maximum daily dose and dosing intervals must be taken into account. Dipyrone is used in children for treatment of visceral pain and cholic. According to the current state of knowledge the rare but severe side effect of agranulocytosis does not justify a general rejection for short-term perioperative administration. OPIOIDS In cases of insufficient analgesia with non-opioid analgesics, the complementary use of opioids is also appropriate for children of all age groups. They are the medication of choice for episodes of medium to strong pain and are administered in a titrated form oriented to effectiveness. If severe pain is expected to last for more than 24 h, patient-controlled anesthesia should be implemented but requires a comprehensive surveillance by nursing personnel. KETAMINE Ketamine is used as an adjuvant in postoperative pain therapy and is recommended for use in pediatric sedation and analgosedation.
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Affiliation(s)
- B Messerer
- Universitätsklinik für Anästhesiologie und Intensivmedizin, Medizinische Universität Graz, LKH-Universitätsklinikum Graz, Auenbruggerplatz 29, 8036, Graz, Österreich,
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13
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Paracetamol potentiates the antidepressant-like and anticompulsive-like effects of fluoxetine. Behav Pharmacol 2015; 26:268-81. [DOI: 10.1097/fbp.0000000000000104] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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Blecharz-Klin K, Joniec-Maciejak I, Piechal A, Pyrzanowska J, Wawer A, Widy-Tyszkiewicz E. Paracetamol impairs the profile of amino acids in the rat brain. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2014; 37:95-102. [PMID: 24316461 DOI: 10.1016/j.etap.2013.11.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2013] [Revised: 10/18/2013] [Accepted: 11/01/2013] [Indexed: 06/02/2023]
Abstract
In our experiment we investigated the effect of subcutaneous administration of paracetamol on the levels of amino acids in the brain structures. Male Wistar rats received for eight weeks paracetamol at two doses: 10 mg/kg b.w. (group P10, n=9) and 50 mg/kg b.w. per day s.c. (group P50, n=9). The regional brain concentrations of amino acids were determined in the prefrontal cortex, hippocampus, hypothalamus and striatum of control (Con, n=9) and paracetamol-treated groups using HPLC. Evaluation of the biochemical results indicated considerable decrease of the content of amino acids in the striatum (glutamine, glutamic acid, taurine, alanine, aspartic acid) and hypothalamus (glycine) between groups treated with paracetamol compared to the control. In the prefrontal cortex paracetamol increased the level of γ-aminobutyric acid (GABA). The present study demonstrated significant effect of the long term paracetamol treatment on the level of amino acids in the striatum, prefrontal cortex and hypothalamus of rats.
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Affiliation(s)
- Kamilla Blecharz-Klin
- Department of Experimental and Clinical Pharmacology, Medical University of Warsaw, Krakowskie Przedmieście 26/28, 00-927 Warsaw, Poland
| | - Ilona Joniec-Maciejak
- Department of Experimental and Clinical Pharmacology, Medical University of Warsaw, Krakowskie Przedmieście 26/28, 00-927 Warsaw, Poland
| | - Agnieszka Piechal
- Department of Experimental and Clinical Pharmacology, Medical University of Warsaw, Krakowskie Przedmieście 26/28, 00-927 Warsaw, Poland
| | - Justyna Pyrzanowska
- Department of Experimental and Clinical Pharmacology, Medical University of Warsaw, Krakowskie Przedmieście 26/28, 00-927 Warsaw, Poland
| | - Adriana Wawer
- Department of Experimental and Clinical Pharmacology, Medical University of Warsaw, Krakowskie Przedmieście 26/28, 00-927 Warsaw, Poland
| | - Ewa Widy-Tyszkiewicz
- Department of Experimental and Clinical Pharmacology, Medical University of Warsaw, Krakowskie Przedmieście 26/28, 00-927 Warsaw, Poland.
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15
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Paracetamol—The outcome on neurotransmission and spatial learning in rats. Behav Brain Res 2013; 253:157-64. [DOI: 10.1016/j.bbr.2013.07.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2013] [Revised: 07/01/2013] [Accepted: 07/07/2013] [Indexed: 12/23/2022]
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16
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Groudine SB, Smith HS, Ellsworth D. Role of intravenous acetaminophen in postoperative pain management. Pain Manag 2012; 2:509-19. [DOI: 10.2217/pmt.12.50] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
SUMMARY The need to safely treat the postoperative pain of patients is apparent. Opioids, although effective, have multiple morbidities associated with their use. A multimodal approach to postoperative pain management can serve to minimize the undesirable effects of opioids. Intravenous acetaminophen (paracetamol) has recently become available in the USA where many practitioners are not familiar with this drug. This article reviews the history, pharmacology and clinical uses of intravenous acetaminophen in the treatment of perioperative pain.
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Affiliation(s)
- Scott B Groudine
- Albany Medical College, Department of Anesthesiology, 47 New Scotland Avenue, MC-131, Albany, NY 12208, USA
| | - Howard S Smith
- Albany Medical College, Department of Anesthesiology, 47 New Scotland Avenue, MC-131, Albany, NY 12208, USA
| | - Duane Ellsworth
- Albany Medical College, Department of Anesthesiology, 47 New Scotland Avenue, MC-131, Albany, NY 12208, USA
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17
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Acetaminophen differentially enhances social behavior and cortical cannabinoid levels in inbred mice. Prog Neuropsychopharmacol Biol Psychiatry 2012; 38:260-9. [PMID: 22542870 PMCID: PMC3389197 DOI: 10.1016/j.pnpbp.2012.04.011] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/13/2012] [Revised: 04/11/2012] [Accepted: 04/11/2012] [Indexed: 11/24/2022]
Abstract
Supratherapeutic doses of the analgesic acetaminophen (paracetomol) are reported to promote social behavior in Swiss mice. However, we hypothesized that it might not promote sociability in other strains due to cannabinoid CB(1) receptor-mediated inhibition of serotonin (5-HT) transmission in the frontal cortex. We examined the effects of acetaminophen on social and repetitive behaviors in comparison to a cannabinoid agonist, WIN 55,212-2, in two strains of socially-deficient mice, BTBR and 129S1/SvImJ (129S). Acetaminophen (100mg/kg) enhanced social interactions in BTBR, and social novelty preference and marble burying in 129S at serum levels of ≥70 ng/ml. Following acetaminophen injection or sociability testing, anandamide (AEA) increased in BTBR frontal cortex, while behavior testing increased 2-arachidonyl glycerol (2-AG) levels in 129S frontal cortex. In contrast, WIN 55,212-2 (0.1mg/kg) did not enhance sociability. Further, we expected CB(1)-deficient (+/-) mice to be less social than wild-type, but instead found similar sociability. Given strain differences in endocannabinoid response to acetaminophen, we compared cortical CB(1) and 5-HT(1A) receptor density and function relative to sociable C57BL/6 mice. CB(1) receptor saturation binding (Bmax=958±117 fmol/mg protein), and affinity for [(3)H] CP55,940 (K(D)=3±0.8 nM) was similar in frontal cortex among strains. CP55,940-stimulated [(35)S] GTPγS binding in cingulate cortex was 136±12, 156±22, and 75±9% above basal in BTBR, 129S and C57BL/6 mice. The acetaminophen metabolite para-aminophenol (1 μM) failed to stimulate [(35)S] GTPγS binding. Hence, it appears that other indirect actions of acetaminophen, including 5-HT receptor agonism, may underlie its sociability promoting properties outweighing any CB(1) mediated suppression by locally-elevated endocannabinoids in these mice.
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18
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Lasko B, Levitt RJ, Rainsford KD, Bouchard S, Rozova A, Robertson S. Extended-release tramadol/paracetamol in moderate-to-severe pain: a randomized, placebo-controlled study in patients with acute low back pain. Curr Med Res Opin 2012; 28:847-57. [PMID: 22458917 DOI: 10.1185/03007995.2012.681035] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
OBJECTIVE Combinations of oral analgesics may offer several potential benefits compared with an individual agent. The objective of this study was to investigate the efficacy and safety of an extended-release, twice-daily fixed combination of 75 mg tramadol/650 mg paracetamol (DDS-06C) in the treatment of moderate-to-severe pain, using acute low back pain as a model. RESEARCH DESIGN AND METHODS In this phase III study, 277 patients with moderate-to-severe acute low back pain were randomized to 1-2 tablets of DDS-06C or placebo every 10-12 h for 2.5 days during the double-blind phase. Following the double-blind phase, patients had the option to continue for a 2.5-day open-label phase. CLINICAL TRIAL REGISTRATION Clinicaltrials.gov (Identifier: NCT00643383) MAIN OUTCOME MEASURES The primary end point was the sum of pain intensity differences (SPID) over the 50-h double-blind phase (SPID50). Secondary end points included total pain relief score over the 50-h double-blind phase (TOTPAR50), patient's global impression of medication, and SPID over the first 4 h. RESULTS A statistically significant (p = 0.038) greater decrease in pain intensity was observed in the DDS-06C group (median SPID50: -6.0) versus placebo (median SPID50: -4.0). Greater pain relief was also observed in patients randomized to DDS-06C: the median TOTPAR50 was 13.0 for the DDS-06C group and 11.0 for placebo (p = 0.026). DDS-06C demonstrated statistically significant superior efficacy compared with placebo for the majority of the other secondary end points. Overall, 38% of patients treated with DDS-06C experienced at least one adverse event; the intensity was mild-to-moderate in 81% of cases. The most commonly reported adverse events (>5% of patients receiving DDS-06C) were nausea, dizziness, vomiting, and somnolence. CONCLUSIONS Using acute low back pain, a model with a high degree of heterogeneity and intrinsic variability, DDS-06C was superior to placebo on measures of pain intensity and relief, and was well-tolerated.
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Affiliation(s)
- Ben Lasko
- Medical Director, Manna Research, Toronto, Ontario, Canada
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Im KS, Jung HJ, Kim JB, Lee JM, Park HJ, Joo CH, Moon DE. The antinociceptive effect of acetaminophen in a rat model of neuropathic pain. Kaohsiung J Med Sci 2012; 28:251-8. [PMID: 22531303 DOI: 10.1016/j.kjms.2011.11.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2011] [Accepted: 08/11/2011] [Indexed: 10/28/2022] Open
Abstract
Acetaminophen is one of the most popular and widely used analgesics for the treatment of pain and fever but few studies have evaluated its effects on neuropathic pain. This study examined the effect of acetaminophen on thermal hyperalgesia, mechanical and cold allodynia in a rat model of neuropathic pain. Male Sprague-Dawley rats were prepared by tightly ligating the left L5 and L6 spinal nerves to produce a model of neuropathic pain. Sixty neuropathic rats were assigned randomly into six groups. Normal saline and acetaminophen (25, 50, 100, 200 and 300 mg/kg) were administered intraperitoneally to these individual groups. Thermal hyperalgesia, mechanical and cold allodynia were examined at preadministration and at 15, 30, 60, 90, 120, 180, 240 and 360 min after administering the drug. Mechanical allodynia was quantified by measuring the paw withdrawal threshold to stimuli with von Frey filaments. Cold allodynia was quantified by measuring the frequency of foot lift after applying 100% acetone. Thermal hyperalgesia was quantified by measuring the thermal withdrawal threshold. The rotarod performance was measured to detect any drug-induced adverse effects, such as drowsiness. The hepatic and renal adverse effect was also assessed by measuring the serum levels of aspartate aminotransferase, alanine aminotransferase, blood urea nitrogen and creatinine. The paw withdrawal thresholds to mechanical stimuli and the thermal withdrawal threshold were increased significantly and withdrawal frequencies to cold stimuli were reduced by acetaminophen administration in a dose-dependent manner. Acetaminophen reduces thermal hyperalgesia, mechanical and cold allodynia in a rat model of neuropathic pain, and might be useful for managing neuropathic pain.
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Affiliation(s)
- Kyong-Shil Im
- Department of Anesthesiology and Pain Medicine, School of Medicine, The Catholic University of Korea, Seoul, South Korea
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20
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Pickering G, Moustafa F, Desbrandes S, Cardot JM, Roux D, Dubray C. Paracetamol and opioid pathways: a pilot randomized clinical trial. Fundam Clin Pharmacol 2011; 27:339-45. [PMID: 22092536 DOI: 10.1111/j.1472-8206.2011.01010.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Previous studies suggest that the antinociceptive action of paracetamol (acetaminophen, APAP) might involve descending inhibitory pain pathways and the opioidergic system: this study explores this issue in humans with naloxone, the opioid antagonist. After ethical approval, 12 healthy male volunteers were included in this randomized, controlled, double-blind, crossover, four-arm study. They were administered intravenous paracetamol (APAP 1 g) or saline (placebo, pl) followed at 100 min with IV naloxone (Nal 8 mg) or saline, every week for 4 weeks. The amplitude of cerebral potentials evoked by thermal/painful stimuli applied on the arm was recorded nine times over 150 min, witnessing of pain integration at central level. Amplitude changes as well as areas under the curve (AUCs) over 150 min were compared for the four treatments by repeated measures ANOVA (significance 0.05). Amplitude changes were significant for APAP/pl vs. pl/pl at t150: -44% (95%CI -58 to -30) vs. -27% (95%CI -37 to -17; P < 0.05) but not vs. APAP/Nal. AUC (0-150) of APAP/pl is significantly different from pl/pl (-3452%.min (95%CI -4705 to -2199) vs. -933% min (95%CI -2273 to 407; P = 0.015) but not from APAP/Nal (-1731% min (95%CI -3676 to 214; P = 0.08) and other treatments. AUC (90-150) is not significantly different. This pilot study shows for the first time in human volunteers that naloxone does not inhibit paracetamol antinociception, suggesting no significant implication of the opioid system in paracetamol mechanism of action: this needs be confirmed on a larger number of subjects.
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Affiliation(s)
- Gisèle Pickering
- CHU Clermont-Ferrand, Centre de Pharmacologie Clinique, F-63003 Clermont-Ferrand, France.
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21
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Toussaint K, Yang XC, Zielinski MA, Reigle KL, Sacavage SD, Nagar S, Raffa RB. What do we (not) know about how paracetamol (acetaminophen) works? J Clin Pharm Ther 2011; 35:617-38. [PMID: 21054454 DOI: 10.1111/j.1365-2710.2009.01143.x] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
WHAT IS KNOWN AND BACKGROUND Although paracetamol (acetaminophen), N-(4-Hydroxyphenyl)acetamide, is one of the world's most widely used analgesics, the mechanism by which it produces its analgesic effect is largely unknown. This lack is relevant because: (i) optimal pain treatment matches the analgesic mechanism to the (patho)physiology of the pain and (ii) modern drug discovery relies on an appropriate screening assay. OBJECTIVE To review the clinical profile and preclinical studies of paracetamol as means of gaining insight into its mechanism of analgesic action. METHODS A literature search was conducted of clinical and preclinical literature and the information obtained was organized and reviewed from the perspective of its contribution to an understanding of the mechanism of analgesic action of paracetamol. RESULTS Paracetamol's broad spectrum of analgesic and other pharmacological actions is presented, along with its multiple postulated mechanism(s) of action. No one mechanism has been definitively shown to account for its analgesic activity. WHAT IS NEW AND CONCLUSION Further research is needed to uncover the mechanism of analgesic action of paracetamol. The lack of this knowledge affects optimal clinical use and impedes drug discovery efforts.
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Affiliation(s)
- K Toussaint
- Temple University School of Pharmacy, Philadelphia, PA 19140, USA
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Abstract
This paper is the thirtieth consecutive installment of the annual review of research concerning the endogenous opioid system. It summarizes papers published during 2007 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior, and the roles of these opioid peptides and receptors in pain and analgesia; stress and social status; tolerance and dependence; learning and memory; eating and drinking; alcohol and drugs of abuse; sexual activity and hormones, pregnancy, development and endocrinology; mental illness and mood; seizures and neurologic disorders; electrical-related activity and neurophysiology; general activity and locomotion; gastrointestinal, renal and hepatic functions; cardiovascular responses; respiration and thermoregulation; and immunological responses.
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Affiliation(s)
- Richard J Bodnar
- Department of Psychology and Neuropsychology Doctoral Sub-Program, Queens College, City University of New York, 65-30 Kissena Blvd.,Flushing, NY 11367, United States.
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23
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Ruggieri V, Vitale G, Pini LA, Sandrini M. Differential involvement of opioidergic and serotonergic systems in the antinociceptive activity of N-arachidonoyl-phenolamine (AM404) in the rat: comparison with paracetamol. Naunyn Schmiedebergs Arch Pharmacol 2008; 377:219-29. [PMID: 18404260 DOI: 10.1007/s00210-008-0284-9] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2008] [Accepted: 03/06/2008] [Indexed: 10/22/2022]
Abstract
It is recognized that paracetamol undergoes a metabolic transformation to N-arachydonylphenolamine (AM404), a CB(1) receptor ligand and anandamide uptake inhibitor. Using hot-plate and paw pressure tests, we decided to establish whether AM404 may act through opioidergic and serotonergic mechanisms. Thus, we pretreated rats with opioid mu(1) (naloxonazine) and kappa (MR2266) or 5-HT(1A) (NAN-190), 5-HT(2) (ketanserin), and 5-HT(3) (ondansetron) receptor antagonists. We investigated the possible changes in 5-hydroxyindoleacetic acid/serotonin ratio in the frontal cortex and pons. The antinociceptive effect of AM404 (10 mg/kg, intraperitoneally) or paracetamol (400 mg/kg, intraperitoneally) in either test was abolished by naloxonazine or MR2266. Ondansetron prevented AM404 activity; NAN-190 and ketanserin were ineffective. Ketanserin antagonized paracetamol activity; NAN-190 and ondansetron were inactive. AM404 did not change serotonergic activity, while paracetamol decreased serotonin turnover. The diverse antinociceptive potency of the compounds might be explained by the different influence on the serotonergic system, despite a similar involvement of opioidergic one.
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MESH Headings
- Acetaminophen/pharmacology
- Analgesics, Non-Narcotic/pharmacology
- Animals
- Arachidonic Acids/pharmacology
- Frontal Lobe/drug effects
- Frontal Lobe/metabolism
- Hydroxyindoleacetic Acid/metabolism
- Male
- Pain/drug therapy
- Pain Measurement
- Pons/drug effects
- Pons/metabolism
- Rats
- Rats, Wistar
- Receptor, Serotonin, 5-HT1A/drug effects
- Receptor, Serotonin, 5-HT1A/metabolism
- Receptors, Opioid, kappa/drug effects
- Receptors, Opioid, kappa/metabolism
- Receptors, Opioid, mu/drug effects
- Receptors, Opioid, mu/metabolism
- Receptors, Serotonin, 5-HT2/drug effects
- Receptors, Serotonin, 5-HT2/metabolism
- Receptors, Serotonin, 5-HT3/drug effects
- Receptors, Serotonin, 5-HT3/metabolism
- Serotonin/metabolism
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Affiliation(s)
- Valentina Ruggieri
- Sect. of Pharmacology, Department of Biomedical Sciences, University of Modena and Reggio Emilia, Via G.Campi 287, 41100 Modena, Italy
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