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Li D, Du H, Qu ST, Wu JL, Li YC, Xu QY, Chen X, Dai XX, Xu JT, Wang Q, Xu GY. Thalamic Nucleus Reuniens Glutamatergic Neurons Mediate Colorectal Visceral Pain in Mice via 5-HT 2B Receptors. Neurosci Bull 2024; 40:1421-1433. [PMID: 38739251 PMCID: PMC11422542 DOI: 10.1007/s12264-024-01207-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Accepted: 12/26/2023] [Indexed: 05/14/2024] Open
Abstract
Irritable bowel syndrome (IBS) is a common functional bowel disorder characterized by abdominal pain and visceral hypersensitivity. Reducing visceral hypersensitivity is the key to effectively relieving abdominal pain in IBS. Increasing evidence has confirmed that the thalamic nucleus reuniens (Re) and 5-hydroxytryptamine (5-HT) neurotransmitter system play an important role in the development of colorectal visceral pain, whereas the exact mechanisms remain largely unclear. In this study, we found that high expression of the 5-HT2B receptors in the Re glutamatergic neurons promoted colorectal visceral pain. Specifically, we found that neonatal maternal deprivation (NMD) mice exhibited visceral hyperalgesia and enhanced spontaneous synaptic transmission in the Re brain region. Colorectal distension (CRD) stimulation induced a large amount of c-Fos expression in the Re brain region of NMD mice, predominantly in glutamatergic neurons. Furthermore, optogenetic manipulation of glutamatergic neuronal activity in the Re altered colorectal visceral pain responses in CON and NMD mice. In addition, we demonstrated that 5-HT2B receptor expression on the Re glutamatergic neurons was upregulated and ultimately promoted colorectal visceral pain in NMD mice. These findings suggest a critical role of the 5HT2B receptors on the Re glutamatergic neurons in the regulation of colorectal visceral pain.
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Affiliation(s)
- Di Li
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and Institute of Neuroscience, Soochow University, Suzhou, 215123, China
| | - Han Du
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and Institute of Neuroscience, Soochow University, Suzhou, 215123, China
| | - Shu-Ting Qu
- Department of Gastroenterology, The First Affiliated Hospital of Soochow University, Suzhou, 215123, China
| | - Jing-Lai Wu
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and Institute of Neuroscience, Soochow University, Suzhou, 215123, China
| | - Yong-Chang Li
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and Institute of Neuroscience, Soochow University, Suzhou, 215123, China
| | - Qi-Ya Xu
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and Institute of Neuroscience, Soochow University, Suzhou, 215123, China
| | - Xia Chen
- Department of Anesthesiology, Children's Hospital of Soochow University, Suzhou, 215123, China
| | - Xiao-Xuan Dai
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and Institute of Neuroscience, Soochow University, Suzhou, 215123, China
| | - Ji-Tian Xu
- Department of Physiology and Neurobiology, College of Basic Medical Sciences, Zhengzhou University, Zhengzhou, 450001, China
| | - Qian Wang
- Department of Anesthesiology, Children's Hospital of Soochow University, Suzhou, 215123, China.
| | - Guang-Yin Xu
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and Institute of Neuroscience, Soochow University, Suzhou, 215123, China.
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Liu T, Li H, Wan Y, Shi G, Zhao Y, Liu Y, Fan X. METTL14-mediated upregulation of lncRNA HOTAIR represses PP1α expression by promoting H3K4me1 demethylation in oxycodone-treated mice. CNS Neurosci Ther 2024; 30:e14830. [PMID: 39046182 PMCID: PMC11267563 DOI: 10.1111/cns.14830] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2024] [Revised: 06/04/2024] [Accepted: 06/15/2024] [Indexed: 07/25/2024] Open
Abstract
N6-methyladenosine (m6A) methylation is a vital epigenetic mechanism associated with drug addiction. However, the relationship between m6A modification and oxycodone rewarding is less well explored. Based on an open field test, the present study evaluated oxycodone rewarding using chromatin immunoprecipitation PCR, immunofluorescence, and RNA sequencing. A marked increase in METTL14 protein and a decrease in PP1α protein due to oxycodone abundance in the striatal neurons were observed in a dose- and time-dependent manner. Oxycodone markedly increased LSD1 expression, and decreased H3K4me1 expression in the striatum. In the open field test, intra-striatal injection of METTL14 siRNA, HOTAIR siRNA, or LSD1 shRNA blocked oxycodone-induced increase in locomotor activity. The downregulation of PP1α was also inhibited after treatment with METTL14/HOTAIR siRNA and LSD1 shRNA. Enhanced binding of LSD1 with CoRest and of CoRest with the PP1α gene induced by oxycodone was also reversed by LSD1 shRNA. In addition, H3K4me1 demethylation was also blocked by the treatment. In summary, the investigation confirmed that METTL14-mediated upregulation of HOTAIR resulted in the repression of PP1α, which in turn facilitated the recruitment of LSD1, thus catalyzing H3K4me1 demethylation and promoting oxycodone addiction.
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Affiliation(s)
- Tian‐Cong Liu
- Department of OtolaryngologyShengjing Hospital of China Medical UniversityShenyangChina
| | - Hong‐Xi Li
- Department of Pain ManagementShengjing Hospital of China Medical UniversityShenyangChina
| | - Yu‐Xiao Wan
- Department of AnesthesiologyShengjing Hospital of China Medical UniversityShenyangChina
| | - Guang Shi
- Department of NeurologyThe People's Hospital of Liaoning ProvinceShenyangChina
| | - Yun‐Peng Zhao
- Department of PharmacyShengjing Hospital of China Medical UniversityShenyangChina
| | - Yi‐Fei Liu
- Department of PharmacyShengjing Hospital of China Medical UniversityShenyangChina
| | - Xin‐Yu Fan
- Department of PharmacyShengjing Hospital of China Medical UniversityShenyangChina
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Cameron LP, Benetatos J, Lewis V, Bonniwell EM, Jaster AM, Moliner R, Castrén E, McCorvy JD, Palner M, Aguilar-Valles A. Beyond the 5-HT 2A Receptor: Classic and Nonclassic Targets in Psychedelic Drug Action. J Neurosci 2023; 43:7472-7482. [PMID: 37940583 PMCID: PMC10634557 DOI: 10.1523/jneurosci.1384-23.2023] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 08/13/2023] [Accepted: 08/18/2023] [Indexed: 11/10/2023] Open
Abstract
Serotonergic psychedelics, such as psilocybin and LSD, have garnered significant attention in recent years for their potential therapeutic effects and unique mechanisms of action. These compounds exert their primary effects through activating serotonin 5-HT2A receptors, found predominantly in cortical regions. By interacting with these receptors, serotonergic psychedelics induce alterations in perception, cognition, and emotions, leading to the characteristic psychedelic experience. One of the most crucial aspects of serotonergic psychedelics is their ability to promote neuroplasticity, the formation of new neural connections, and rewire neuronal networks. This neuroplasticity is believed to underlie their therapeutic potential for various mental health conditions, including depression, anxiety, and substance use disorders. In this mini-review, we will discuss how the 5-HT2A receptor activation is just one facet of the complex mechanisms of action of serotonergic psychedelics. They also interact with other serotonin receptor subtypes, such as 5-HT1A and 5-HT2C receptors, and with neurotrophin receptors (e.g., tropomyosin receptor kinase B). These interactions contribute to the complexity of their effects on perception, mood, and cognition. Moreover, as psychedelic research advances, there is an increasing interest in developing nonhallucinogenic derivatives of these drugs to create safer and more targeted medications for psychiatric disorders by removing the hallucinogenic properties while retaining the potential therapeutic benefits. These nonhallucinogenic derivatives would offer patients therapeutic advantages without the intense psychedelic experience, potentially reducing the risks of adverse reactions. Finally, we discuss the potential of psychedelics as substrates for post-translational modification of proteins as part of their mechanism of action.
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Affiliation(s)
- Lindsay P Cameron
- Department of Psychiatry, Stanford University, Palo Alto 94305, California
| | - Joseph Benetatos
- Department of Neurosciences, University of California-San Diego, La Jolla 92093, California
| | - Vern Lewis
- Department of Neuroscience, Carleton University, Ottawa K1S 5B6, Ontario Canada
| | - Emma M Bonniwell
- Department of Cell Biology, Neurobiology, and Anatomy, Medical College of Wisconsin, Milwaukee 53226, Wisconsin
| | - Alaina M Jaster
- Pharmacology and Toxicology, Physiology and Biophysics, Virginia Commonwealth University, Richmond 23298, Virginia
| | - Rafael Moliner
- Neuroscience Center, HiLIFE and Department of Pharmacology, Faculty of Medicine, University of Helsinki, Helsinki 00014, Finland
| | - Eero Castrén
- Neuroscience Center, HiLIFE and Department of Pharmacology, Faculty of Medicine, University of Helsinki, Helsinki 00014, Finland
| | - John D McCorvy
- Department of Cell Biology, Neurobiology, and Anatomy, Medical College of Wisconsin, Milwaukee 53226, Wisconsin
| | - Mikael Palner
- Clinical Physiology and Nuclear Medicine, Department Clinical Research, University of Southern Denmark, Odense DK-2100, Denmark
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Abstract
This paper is the forty-fifth consecutive installment of the annual anthological review of research concerning the endogenous opioid system, summarizing articles published during 2022 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides and receptors as well as effects of opioid/opiate agonists and antagonists. The review is subdivided into the following specific topics: molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors (1), the roles of these opioid peptides and receptors in pain and analgesia in animals (2) and humans (3), opioid-sensitive and opioid-insensitive effects of nonopioid analgesics (4), opioid peptide and receptor involvement in tolerance and dependence (5), stress and social status (6), learning and memory (7), eating and drinking (8), drug abuse and alcohol (9), sexual activity and hormones, pregnancy, development and endocrinology (10), mental illness and mood (11), seizures and neurologic disorders (12), electrical-related activity and neurophysiology (13), general activity and locomotion (14), gastrointestinal, renal and hepatic functions (15), cardiovascular responses (16), respiration and thermoregulation (17), and immunological responses (18).
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Affiliation(s)
- Richard J Bodnar
- Department of Psychology and Neuropsychology Doctoral Sub-Program, Queens College, City University of New York, Flushing, NY 11367, USA.
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Salinsky LM, Merritt CR, Zamora JC, Giacomini JL, Anastasio NC, Cunningham KA. μ-opioid receptor agonists and psychedelics: pharmacological opportunities and challenges. Front Pharmacol 2023; 14:1239159. [PMID: 37886127 PMCID: PMC10598667 DOI: 10.3389/fphar.2023.1239159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Accepted: 09/28/2023] [Indexed: 10/28/2023] Open
Abstract
Opioid misuse and opioid-involved overdose deaths are a massive public health problem involving the intertwined misuse of prescription opioids for pain management with the emergence of extremely potent fentanyl derivatives, sold as standalone products or adulterants in counterfeit prescription opioids or heroin. The incidence of repeated opioid overdose events indicates a problematic use pattern consistent with the development of the medical condition of opioid use disorder (OUD). Prescription and illicit opioids reduce pain perception by activating µ-opioid receptors (MOR) localized to the central nervous system (CNS). Dysregulation of meso-corticolimbic circuitry that subserves reward and adaptive behaviors is fundamentally involved in the progressive behavioral changes that promote and are consequent to OUD. Although opioid-induced analgesia and the rewarding effects of abused opioids are primarily mediated through MOR activation, serotonin (5-HT) is an important contributor to the pharmacology of opioid abused drugs (including heroin and prescription opioids) and OUD. There is a recent resurgence of interest into psychedelic compounds that act primarily through the 5-HT2A receptor (5-HT 2A R) as a new frontier in combatting such diseases (e.g., depression, anxiety, and substance use disorders). Emerging data suggest that the MOR and 5-HT2AR crosstalk at the cellular level and within key nodes of OUD circuitry, highlighting a major opportunity for novel pharmacological intervention for OUD. There is an important gap in the preclinical profiling of psychedelic 5-HT2AR agonists in OUD models. Further, as these molecules carry risks, additional analyses of the profiles of non-hallucinogenic 5-HT2AR agonists and/or 5-HT2AR positive allosteric modulators may provide a new pathway for 5-HT2AR therapeutics. In this review, we discuss the opportunities and challenges associated with utilizing 5-HT2AR agonists as therapeutics for OUD.
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Affiliation(s)
| | | | | | | | - Noelle C. Anastasio
- Center for Addiction Sciences and Therapeutics and Department of Pharmacology and Toxicology, John Sealy School of Medicine, University of Texas Medical Branch, Galveston, TX, United States
| | - Kathryn A. Cunningham
- Center for Addiction Sciences and Therapeutics and Department of Pharmacology and Toxicology, John Sealy School of Medicine, University of Texas Medical Branch, Galveston, TX, United States
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Saha S, González-Maeso J. The crosstalk between 5-HT 2AR and mGluR2 in schizophrenia. Neuropharmacology 2023; 230:109489. [PMID: 36889432 PMCID: PMC10103009 DOI: 10.1016/j.neuropharm.2023.109489] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Revised: 02/26/2023] [Accepted: 03/05/2023] [Indexed: 03/08/2023]
Abstract
Schizophrenia is a severe brain disorder that usually produces a lifetime of disability. First generation or typical antipsychotics such as haloperidol and second generation or atypical antipsychotics such as clozapine and risperidone remain the current standard for schizophrenia treatment. In some patients with schizophrenia, antipsychotics produce complete remission of positive symptoms, such as hallucinations and delusions. However, antipsychotic drugs are ineffective against cognitive deficits and indeed treated schizophrenia patients have small improvements or even deterioration in several cognitive domains. This underlines the need for novel and more efficient therapeutic targets for schizophrenia treatment. Serotonin and glutamate have been identified as key parts of two neurotransmitter systems involved in fundamental brain processes. Serotonin (or 5-hydroxytryptamine) 5-HT2A receptor (5-HT2AR) and metabotropic glutamate 2 receptor (mGluR2) are G protein-coupled receptors (GPCRs) that interact at epigenetic and functional levels. These two receptors can form GPCR heteromeric complexes through which their pharmacology, function and trafficking becomes affected. Here we review past and current research on the 5-HT2AR-mGluR2 heterocomplex and its potential implication in schizophrenia and antipsychotic drug action. This article is part of the Special Issue on "The receptor-receptor interaction as a new target for therapy".
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Affiliation(s)
- Somdatta Saha
- Department of Physiology and Biophysics, Virginia Commonwealth University School of Medicine, Richmond, VA, 23298, USA
| | - Javier González-Maeso
- Department of Physiology and Biophysics, Virginia Commonwealth University School of Medicine, Richmond, VA, 23298, USA.
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Maguire DR. Effects of 2,5-Dimethoxy-4-Methylamphetamine (DOM) and 2-Piperazin-1-yl-Quinoline (Quipazine) on Fentanyl Versus Food Choice in Rhesus Monkeys. J Pharmacol Exp Ther 2023; 384:155-162. [PMID: 36272734 PMCID: PMC9827501 DOI: 10.1124/jpet.122.001318] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 08/18/2022] [Accepted: 10/03/2022] [Indexed: 11/06/2022] Open
Abstract
There has been increasing interest in the potential therapeutic effects of drugs with agonist properties at serotonin 2A subtype (5-HT2A) receptors (e.g., psychedelics), including treatment of substance use disorders. Studying interactions between 5-HT2A receptor agonists and other drugs is important for understanding potential therapeutic effects as well as adverse interactions. Direct-acting 5-HT2A receptor agonists such as 2,5-dimethoxy-4-methylamphetamine (DOM) and 2-piperazin-1-yl-quinoline (quipazine) enhance some (e.g., antinociceptive) effects of opioids; however, it is unclear whether they alter the abuse-related effects of opioids. This study examined whether DOM and quipazine alter the reinforcing effects of fentanyl in rhesus monkeys (n = 6) responding under a food versus drug choice procedure. Responding on one lever delivered sucrose pellets and responding on the other lever delivered intravenous (i.v.) infusions. In one set of experiments, fentanyl (0.1-3.2 µg/kg/infusion) versus food choice sessions were preceded by noncontingent i.v. pretreatments with DOM (0032-0.32 mg/kg), quipazine (0.32-1.0 mg/kg), naltrexone (0.032 mg/kg), or heroin (0.1 mg/kg). In another set of experiments, fentanyl was available during choice sessions in combination with DOM (0.32-100 µg/kg/infusion) or quipazine (3.2-320 µg/kg/infusion) in varying dose ratios. Naltrexone decreased and heroin increased fentanyl choice, demonstrating sensitivity of responding to pharmacological manipulation. However, whether given as a pretreatment or made available in combination with fentanyl as a mixture, neither DOM nor quipazine significantly altered fentanyl choice. These results suggest that 5-HT2A receptor agonists do not enhance the reinforcing effects of opioids and, thus, will not likely enhance abuse potential. SIGNIFICANCE STATEMENT: Serotonin 2A subtype receptor agonists enhance some (e.g., antinociceptive) effects of opioids, suggesting they could be combined with opioids in some therapeutic contexts such as treating pain. However, it is unclear whether they also enhance adverse effects of opioids, including abuse. Results of this study indicate that serotonin 2A subtype receptor agonists do not reliably enhance opioid self-administration and, thus, are unlikely to enhance the abuse potential of opioids.
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Affiliation(s)
- David R Maguire
- Department of Pharmacology and Addiction Research, Treatment & Training Center of Excellence, University of Texas Health Science Center at San Antonio, San Antonio, Texas
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8
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Jaster AM, Younkin J, Cuddy T, de la Fuente Revenga M, Poklis JL, Dozmorov MG, González-Maeso J. Differences across sexes on head-twitch behavior and 5-HT 2A receptor signaling in C57BL/6J mice. Neurosci Lett 2022; 788:136836. [PMID: 35963476 PMCID: PMC10114867 DOI: 10.1016/j.neulet.2022.136836] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Revised: 07/27/2022] [Accepted: 08/08/2022] [Indexed: 01/26/2023]
Abstract
Psychedelics, also known as classical hallucinogens, affect processes related to perception, cognition and sensory processing mostly via the serotonin 5-HT2A receptor (5-HT2AR). This class of psychoactive substances, which includes lysergic acid diethylamide (LSD), psilocybin, mescaline and the substituted amphetamine 1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI), is receiving renewed attention for their potential therapeutic properties as it relates to psychiatric conditions such as depression and substance use disorders. Current studies focused on the potentially clinical effects of psychedelics on human subjects tend to exclude sex as a biological variable. Much of the understanding of psychedelic pharmacology is derived from rodent models, but most of this preclinical research has only focused on male mice. Here we tested the effects of DOI on head-twitch behavior (HTR) - a mouse behavioral proxy of human psychedelic potential - in male and female mice. DOI elicited more HTR in female as compared to male C57BL/6J mice, a sex-specific exacerbated behavior that was not observed in 129S6/SvEv animals. Volinanserin (or M100907) - a 5-HT2AR antagonist - fully prevented DOI-induced HTR in male and female C57BL/6J mice. Accumulation of inositol monophosphate (IP1) in the frontal cortex upon DOI administration showed no sex-related effect in C57BL/6J mice. However, the pharmacokinetic properties of DOI differed among sexes - brain and plasma concentrations of DOI were lower 30 and 60 min after drug administration in female as compared to male C57BL/6J mice. Together, these results suggest strain-dependent and sex-related differences in the behavioral and pharmacokinetic profiles of the 5-HT2AR agonist DOI in C57BL/6J mice, and support the importance of studying sex as a biological variable in preclinical psychedelic research.
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Affiliation(s)
- Alaina M Jaster
- Department of Physiology & Biophysics, Virginia Commonwealth University School of Medicine, Richmond, VA 23298, United States; Department of Pharmacology & Toxicology, Virginia Commonwealth University School of Medicine, Richmond, VA 23298, United States
| | - Jason Younkin
- Department of Physiology & Biophysics, Virginia Commonwealth University School of Medicine, Richmond, VA 23298, United States; Virginia Institute of Psychiatric and Behavioral Genetics, Virginia Commonwealth University School of Medicine, Richmond, VA 23298, United States
| | - Travis Cuddy
- Department of Physiology & Biophysics, Virginia Commonwealth University School of Medicine, Richmond, VA 23298, United States
| | - Mario de la Fuente Revenga
- Department of Physiology & Biophysics, Virginia Commonwealth University School of Medicine, Richmond, VA 23298, United States; Virginia Institute of Psychiatric and Behavioral Genetics, Virginia Commonwealth University School of Medicine, Richmond, VA 23298, United States
| | - Justin L Poklis
- Department of Pharmacology & Toxicology, Virginia Commonwealth University School of Medicine, Richmond, VA 23298, United States
| | - Mikhail G Dozmorov
- Department of Biostatistics, Virginia Commonwealth University School of Medicine, Richmond, VA 23298, United States
| | - Javier González-Maeso
- Department of Physiology & Biophysics, Virginia Commonwealth University School of Medicine, Richmond, VA 23298, United States.
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de la Fuente Revenga M, Jaster AM, McGinn J, Silva G, Saha S, González-Maeso J. Tolerance and Cross-Tolerance among Psychedelic and Nonpsychedelic 5-HT 2A Receptor Agonists in Mice. ACS Chem Neurosci 2022; 13:2436-2448. [PMID: 35900876 PMCID: PMC10411500 DOI: 10.1021/acschemneuro.2c00170] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Classical psychedelics represent a subgroup of serotonergic psychoactive substances characterized by their distinct subjective effects on the human psyche. Another unique attribute of this drug class is that such effects become less apparent after repeated exposure within a short time span. The classification of psychedelics as a subgroup within the serotonergic drug family and the tolerance to their effects are replicated by the murine head twitch response (HTR) behavioral paradigm. Here, we aimed to assess tolerance and cross-tolerance to HTR elicited by psychedelic and nonpsychedelic serotonin 2A receptor (5-HT2AR) agonists in mice. We show that repeated (4 days) administration of the psychedelic 1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI) induced a progressive decrease in HTR behavior. Tolerance to DOI-induced HTR was also observed 24 h after a single administration of this psychedelic. Pretreatment with the 5-HT2AR antagonist M100907 reduced not only the acute manifestation of DOI-induced HTR, but also the development of tolerance to HTR. Additionally, cross-tolerance became apparent between the psychedelics DOI and lysergic acid diethylamide (LSD), whereas repeated administration of the nonpsychedelic 5-HT2AR agonist lisuride did not affect the ability of these two psychedelics to induce HTR. At the molecular level, DOI administration led to down-regulation of 5-HT2AR density in mouse frontal cortex membrane preparations. However, development of tolerance to the effect of DOI on HTR remained unchanged in β-arrestin-2 knockout mice. Together, these data suggest that tolerance to HTR induced by psychedelics involves activation of the 5-HT2AR, is not observable upon repeated administration of nonpsychedelic 5-HT2AR agonists, and occurs via a signaling mechanism independent of β-arrestin-2.
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Affiliation(s)
- Mario de la Fuente Revenga
- Department of Physiology & Biophysics, Virginia Commonwealth University School of Medicine, Richmond, Virginia 23298, United States
- Virginia Institute of Psychiatric and Behavioral Genetics, Virginia Commonwealth University, Richmond, Virginia 23298, United States
| | - Alaina M Jaster
- Department of Physiology & Biophysics, Virginia Commonwealth University School of Medicine, Richmond, Virginia 23298, United States
- Department of Pharmacology & Toxicology, Virginia Commonwealth University School of Medicine, Richmond, Virginia 23298, United States
| | - John McGinn
- Department of Physiology & Biophysics, Virginia Commonwealth University School of Medicine, Richmond, Virginia 23298, United States
| | - Gabriella Silva
- Department of Physiology & Biophysics, Virginia Commonwealth University School of Medicine, Richmond, Virginia 23298, United States
| | - Somdatta Saha
- Department of Physiology & Biophysics, Virginia Commonwealth University School of Medicine, Richmond, Virginia 23298, United States
| | - Javier González-Maeso
- Department of Physiology & Biophysics, Virginia Commonwealth University School of Medicine, Richmond, Virginia 23298, United States
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