1
|
Collins HM, Gullino LS, Ozdemir D, Lazarenco C, Sudarikova Y, Daly E, Pilar Cuéllar F, Pinacho R, Bannerman DM, Sharp T. Rebound activation of 5-HT neurons following SSRI discontinuation. Neuropsychopharmacology 2024:10.1038/s41386-024-01857-8. [PMID: 38609530 DOI: 10.1038/s41386-024-01857-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Revised: 03/12/2024] [Accepted: 04/01/2024] [Indexed: 04/14/2024]
Abstract
Cessation of therapy with a selective serotonin (5-HT) reuptake inhibitor (SSRI) is often associated with an early onset and disabling discontinuation syndrome, the mechanism of which is surprisingly little investigated. Here we determined the effect on 5-HT neurochemistry of discontinuation from the SSRI paroxetine. Paroxetine was administered repeatedly to mice (once daily, 12 days versus saline controls) and then either continued or discontinued for up to 5 days. Whereas brain tissue levels of 5-HT and/or its metabolite 5-HIAA tended to decrease during continuous paroxetine, levels increased above controls after discontinuation, notably in hippocampus. In microdialysis experiments continuous paroxetine elevated hippocampal extracellular 5-HT and this effect fell to saline control levels on discontinuation. However, depolarisation (high potassium)-evoked 5-HT release was reduced by continuous paroxetine but increased above controls post-discontinuation. Extracellular hippocampal 5-HIAA also decreased during continuous paroxetine and increased above controls post-discontinuation. Next, immunohistochemistry experiments found that paroxetine discontinuation increased c-Fos expression in midbrain 5-HT (TPH2 positive) neurons, adding further evidence for a hyperexcitable 5-HT system. The latter effect was recapitulated by 5-HT1A receptor antagonist administration although gene expression analysis could not confirm altered expression of 5-HT1A autoreceptors following paroxetine discontinuation. Finally, in behavioural experiments paroxetine discontinuation increased anxiety-like behaviour, which partially correlated in time with the measures of increased 5-HT function. In summary, this study reports evidence that, across a range of experiments, SSRI discontinuation triggers a rebound activation of 5-HT neurons. This effect is reminiscent of neural changes associated with various psychotropic drug withdrawal states, suggesting a common unifying mechanism.
Collapse
Affiliation(s)
- Helen M Collins
- Dept. of Pharmacology, University of Oxford, Oxford, UK
- Dept. of Experimental Psychology, University of Oxford, Oxford, UK
| | | | - Dersu Ozdemir
- Dept. of Pharmacology, University of Oxford, Oxford, UK
| | | | | | | | - Fuencisla Pilar Cuéllar
- Dept. of Pharmacology, University of Oxford, Oxford, UK
- Departamento de Señalización Molecular y Celular, Instituto de Biomedicina y Biotecnología de Cantabria (IBBTEC), Departamento de Fisiología y Farmacología, Facultad de Medicina, Universidad de Cantabria, Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Instituto de Salud Carlos III, Santander, Spain
| | - Raquel Pinacho
- Dept. of Experimental Psychology, University of Oxford, Oxford, UK
| | | | - Trevor Sharp
- Dept. of Pharmacology, University of Oxford, Oxford, UK.
| |
Collapse
|
2
|
Belloch FDB, Cortés-Erice M, Herzog E, Zhang XM, Díaz-Perdigon T, Puerta E, Tordera RM. Fast antidepressant action of ketamine in mouse models requires normal VGLUT1 levels from prefrontal cortex neurons. Prog Neuropsychopharmacol Biol Psychiatry 2023; 121:110640. [PMID: 36209771 DOI: 10.1016/j.pnpbp.2022.110640] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/12/2022] [Revised: 09/03/2022] [Accepted: 09/12/2022] [Indexed: 11/07/2022]
Abstract
The NMDA antagonist ketamine demonstrated a fast antidepressant activity in treatment-resistant depression. Pre-clinical studies suggest that de novo synthesis of the brain-derived neurotrophic factor (BDNF) in the PFC might be involved in the rapid antidepressant action of ketamine. Applying a genetic model of impaired glutamate release, this study aims to further identify the molecular mechanisms that could modulate antidepressant action and resistance to treatment. To that end, mice knocked-down for the vesicular glutamate transporter 1 (VGLUT1+/-) were used. We analyzed anhedonia and helpless behavior as well as the expression of the proteins linked to glutamate transmission in the PFC of mice treated with ketamine or the reference antidepressant reboxetine. Moreover, we analyzed the acute effects of ketamine in VGLUT1+/- mice pretreated with chronic reboxetine or those that received a PFC rescue expression of VGLUT1. Chronic reboxetine rescued the depressive-like phenotype of the VGLUT1+/- mice. In addition, it enhanced the expression of the proteins linked to the AMPA signaling pathway as well as the immature form of BDNF (pro-BDNF). Unlike WT mice, ketamine had no effect on anhedonia or pro-BDNF expression in VGLUT1+/- mice; it also failed to decrease phosphorylated eukaryote elongation factor 2 (p-eEF2). Nevertheless, we found that reboxetine administered as pretreatment or PFC overexpression of VGLUT1 did rescue the antidepressant-like activity of acute ketamine in the mice. Our results strongly suggest that not only do PFC VGLUT1 levels modulate the rapid-antidepressant action of ketamine, but also highlight a possible mechanism for antidepressant resistance in some patients.
Collapse
Affiliation(s)
| | - María Cortés-Erice
- Department of Pharmacology and Toxicology, University of Navarra, 31008 Pamplona, Spain
| | - Etienne Herzog
- Université de Bordeaux, Univ. Bordeaux, CNRS, Interdisciplinary Institute for Neuroscience, IINS, UMR 5297, F-33000 Bordeaux, France
| | - Xiao Min Zhang
- Université de Bordeaux, Univ. Bordeaux, CNRS, Interdisciplinary Institute for Neuroscience, IINS, UMR 5297, F-33000 Bordeaux, France
| | - Teresa Díaz-Perdigon
- Department of Pharmacology and Toxicology, University of Navarra, 31008 Pamplona, Spain
| | - Elena Puerta
- Department of Pharmacology and Toxicology, University of Navarra, 31008 Pamplona, Spain
| | - Rosa M Tordera
- Department of Pharmacology and Toxicology, University of Navarra, 31008 Pamplona, Spain.
| |
Collapse
|
3
|
Grossman CD, Bari BA, Cohen JY. Serotonin neurons modulate learning rate through uncertainty. Curr Biol 2022; 32:586-599.e7. [PMID: 34936883 PMCID: PMC8825708 DOI: 10.1016/j.cub.2021.12.006] [Citation(s) in RCA: 40] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Revised: 10/11/2021] [Accepted: 12/03/2021] [Indexed: 12/20/2022]
Abstract
Regulating how fast to learn is critical for flexible behavior. Learning about the consequences of actions should be slow in stable environments, but accelerate when that environment changes. Recognizing stability and detecting change are difficult in environments with noisy relationships between actions and outcomes. Under these conditions, theories propose that uncertainty can be used to modulate learning rates ("meta-learning"). We show that mice behaving in a dynamic foraging task exhibit choice behavior that varied as a function of two forms of uncertainty estimated from a meta-learning model. The activity of dorsal raphe serotonin neurons tracked both types of uncertainty in the foraging task as well as in a dynamic Pavlovian task. Reversible inhibition of serotonin neurons in the foraging task reproduced changes in learning predicted by a simulated lesion of meta-learning in the model. We thus provide a quantitative link between serotonin neuron activity, learning, and decision making.
Collapse
Affiliation(s)
- Cooper D Grossman
- The Solomon H. Snyder Department of Neuroscience, Brain Science Institute, Kavli Neuroscience Discovery Institute, The Johns Hopkins University School of Medicine, 725 N. Wolfe Street, Baltimore, MD 21205, USA
| | - Bilal A Bari
- The Solomon H. Snyder Department of Neuroscience, Brain Science Institute, Kavli Neuroscience Discovery Institute, The Johns Hopkins University School of Medicine, 725 N. Wolfe Street, Baltimore, MD 21205, USA
| | - Jeremiah Y Cohen
- The Solomon H. Snyder Department of Neuroscience, Brain Science Institute, Kavli Neuroscience Discovery Institute, The Johns Hopkins University School of Medicine, 725 N. Wolfe Street, Baltimore, MD 21205, USA.
| |
Collapse
|
4
|
Liang Y, Shi W, Xiang A, Hu D, Wang L, Zhang L. The NAergic locus coeruleus-ventrolateral preoptic area neural circuit mediates rapid arousal from sleep. Curr Biol 2021; 31:3729-3742.e5. [PMID: 34270948 DOI: 10.1016/j.cub.2021.06.031] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2021] [Revised: 04/26/2021] [Accepted: 06/10/2021] [Indexed: 01/04/2023]
Abstract
The locus coeruleus (LC), which is located in the brain stem, plays an important role in promoting arousal. However, the neural circuitry underlying this function remains unclear. Using cortical electroencephalography combined with optrode recording, we found that LC noradrenergic (LCNA) neurons exhibit high activity during wakefulness, while suppressing the activity of these neurons causes a reduction in wakefulness. Viral tracing showed that LCNA neurons directly project to the ventrolateral preoptic area (VLPO) and that optogenetic activation of the noradrenergic (NAergic) LC-VLPO (NAergicLC-VLPO) neural circuit promotes arousal. Optrode recordings in the VLPO revealed two functionally distinct neuronal populations that were stimulated in response to the optogenetic activation of LCNA neurons. Consistently, we identified two types of VLPO neurons that exhibited different responses to NAergic projections from the LC mediated by discrete adrenergic receptors. Together, our results demonstrate that the NAergicLC-VLPO neural circuit is a critical pathway for controlling wakefulness and that a synergistic effect is produced by inhibition of sleep-active neurons in the VLPO through α2 receptors and activation of wake-active neurons in the VLPO through α1 and β receptors.
Collapse
Affiliation(s)
- Yue Liang
- Department of Pharmacology, School of Basic Medical Sciences, Anhui Medical University, Hefei 230000, China; The First Rehabilitation Hospital of Shanghai, Tongji University School of Medicine, Shanghai 200090, China
| | - Wu Shi
- The First Rehabilitation Hospital of Shanghai, Tongji University School of Medicine, Shanghai 200090, China
| | - Anfeng Xiang
- The First Rehabilitation Hospital of Shanghai, Tongji University School of Medicine, Shanghai 200090, China; Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration of Ministry of Education, Orthopaedic Department of Tongji Hospital, School of Medicine, Tongji University, 389 Xincun Road, 200065 Shanghai, P. R. China
| | - Dandan Hu
- The First Rehabilitation Hospital of Shanghai, Tongji University School of Medicine, Shanghai 200090, China; Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration of Ministry of Education, Orthopaedic Department of Tongji Hospital, School of Medicine, Tongji University, 389 Xincun Road, 200065 Shanghai, P. R. China
| | - Liecheng Wang
- Department of Pharmacology, School of Basic Medical Sciences, Anhui Medical University, Hefei 230000, China.
| | - Ling Zhang
- The First Rehabilitation Hospital of Shanghai, Tongji University School of Medicine, Shanghai 200090, China; Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration of Ministry of Education, Orthopaedic Department of Tongji Hospital, School of Medicine, Tongji University, 389 Xincun Road, 200065 Shanghai, P. R. China.
| |
Collapse
|
5
|
Delcourte S, Etievant A, Haddjeri N. Role of central serotonin and noradrenaline interactions in the antidepressants' action: Electrophysiological and neurochemical evidence. PROGRESS IN BRAIN RESEARCH 2021; 259:7-81. [PMID: 33541681 DOI: 10.1016/bs.pbr.2021.01.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The development of antidepressant drugs, in the last 6 decades, has been associated with theories based on a deficiency of serotonin (5-HT) and/or noradrenaline (NA) systems. Although the pathophysiology of major depression (MD) is not fully understood, numerous investigations have suggested that treatments with various classes of antidepressant drugs may lead to an enhanced 5-HT and/or adapted NA neurotransmissions. In this review, particular morpho-physiological aspects of these systems are first considered. Second, principal features of central 5-HT/NA interactions are examined. In this regard, the effects of the acute and sustained antidepressant administrations on these systems are discussed. Finally, future directions including novel therapeutic strategies are proposed.
Collapse
Affiliation(s)
- Sarah Delcourte
- Univ Lyon, Université Claude Bernard Lyon 1, Inserm, Stem Cell and Brain Research Institute U1208, Bron, France
| | - Adeline Etievant
- Integrative and Clinical Neurosciences EA481, University of Bourgogne Franche-Comté, Besançon, France
| | - Nasser Haddjeri
- Univ Lyon, Université Claude Bernard Lyon 1, Inserm, Stem Cell and Brain Research Institute U1208, Bron, France.
| |
Collapse
|
6
|
Jiang JL, El Mansari M, Blier P. Triple reuptake inhibition of serotonin, norepinephrine, and dopamine increases the tonic activation of α 2-adrenoceptors in the rat hippocampus and dopamine levels in the nucleus accumbens. Prog Neuropsychopharmacol Biol Psychiatry 2020; 103:109987. [PMID: 32474007 DOI: 10.1016/j.pnpbp.2020.109987] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Revised: 05/26/2020] [Accepted: 05/26/2020] [Indexed: 01/03/2023]
Abstract
Clinical studies have shown the therapeutic efficacy of an increase in dopamine (DA) transmission in treatment of major depressive disorder (MDD). In the present study, we investigated whether blockade of DA transporters in addition to serotonin (5-HT) and norepinephrine (NE) produced additional adaptations of monoaminergic systems. In vivo electrophysiological recordings were carried out in male anesthetized rats. Vehicle, the 5-HT reuptake inhibitor escitalopram, the NE/DA reuptake blocker nomifensine and their combination (triple reuptake inhibition; TRI) were delivered for 2 or 14 days. Firing activity of NE, 5-HT and DA neurons was assessed. Tonic activation of 5-HT1A receptors and α1- and α2-adrenoceptors was determined in the hippocampus and extracellular DA levels in the nucleus accumbens (NAc). Unlike escitalopram, nomifensine and TRI administration increased the tonic activation of α2-adrenoceptors in the hippocampus despite decreasing NE neuronal firing activity after 2 and 14 days of administration. The firing activity of 5-HT neurons was increased after prolonged nomifensine and TRI regimens, while addition of nomifensine to escitalopram prevented the early 2-day suppression of firing by 5-HT reuptake inhibition. The tonic activation of 5-HT1A receptors was enhanced only with escitalopram. Whereas escitalopram and nomifensine decreased firing activity of DA neurons after a 2-day administration, their combination normalized it to baseline level after 14 days; this was accompanied by a robust increase in extracellular DA levels in the NAc. In summary, these results indicate that TRI increases NE and DA but not 5-HT transmission, suggesting a differential efficacy profile in MDD patients.
Collapse
Affiliation(s)
- Jojo L Jiang
- University of Ottawa Institute of Mental Health Research, 1145 Carling Avenue, Ottawa, Ontario K1Z 7K4, Canada
| | - Mostafa El Mansari
- University of Ottawa Institute of Mental Health Research, 1145 Carling Avenue, Ottawa, Ontario K1Z 7K4, Canada.
| | - Pierre Blier
- University of Ottawa Institute of Mental Health Research, 1145 Carling Avenue, Ottawa, Ontario K1Z 7K4, Canada
| |
Collapse
|
7
|
El Mansari M, Ebrahimzadeh M, Hamati R, Iro CM, Farkas B, Kiss B, Adham N, Blier P. Long-term administration of cariprazine increases locus coeruleus noradrenergic neurons activity and serotonin 1A receptor neurotransmission in the hippocampus. J Psychopharmacol 2020; 34:1143-1154. [PMID: 32684081 DOI: 10.1177/0269881120936891] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
BACKGROUND Cariprazine, the novel dopamine (DA) D3-preferring D3/D2 and serotonin (5-HT)1A receptor partial agonist, has activity as an adjunctive therapy in major depressive disorder (MDD). AIMS This study aims to investigate the effects of chronic cariprazine administration in combination with the selective serotonin reuptake inhibitor escitalopram on the activity of monoaminergic systems. METHODS Rats received cariprazine alone and in adjunct to escitalopram for 2 and 14 days and the firing activity of dorsal raphe nucleus 5-HT, locus coeruleus norepinephrine (NE) and ventral tegmental area DA neurons was assessed. 5-HT and NE neurotransmission in hippocampus pyramidal neurons was evaluated by assessing tonic activation of their 5-HT1A, and α1- and α2-adrenergic receptors, using their selective antagonists. RESULTS Two and 14-day cariprazine regimens increased the firing rate of NE, but not 5-HT and DA neurons. Addition of cariprazine to escitalopram reversed the inhibitory effect of escitalopram on NE but not 5-HT and DA neurons. In the hippocampus, there was an increase in neurotransmission at 5-HT1A receptors in cariprazine-treated rats, but no change in overall NE transmission by either regimen. CONCLUSION Cariprazine increased NE neuronal firing and reversed the escitalopram-induced inhibition of these neurons. Despite a lack of effect on 5-HT neuronal firing activity, there was an increase in tonic activation of hippocampus 5-HT1A receptors by cariprazine alone but not with the combination. These effects provide a possible rationale for the clinical efficacy of cariprazine as an adjunctive strategy in patients with MDD.
Collapse
Affiliation(s)
- Mostafa El Mansari
- Mood Disorders Research Unit, University of Ottawa Institute of Mental Health Research, Ottawa, ON, Canada
| | - Mohammad Ebrahimzadeh
- Mood Disorders Research Unit, University of Ottawa Institute of Mental Health Research, Ottawa, ON, Canada
| | - Rami Hamati
- Mood Disorders Research Unit, University of Ottawa Institute of Mental Health Research, Ottawa, ON, Canada
| | - Chidibere M Iro
- Mood Disorders Research Unit, University of Ottawa Institute of Mental Health Research, Ottawa, ON, Canada
| | | | - Béla Kiss
- Gedeon Richter Plc, Budapest, Hungary
| | | | - Pierre Blier
- Mood Disorders Research Unit, University of Ottawa Institute of Mental Health Research, Ottawa, ON, Canada
| |
Collapse
|
8
|
Lustberg D, Iannitelli AF, Tillage RP, Pruitt M, Liles LC, Weinshenker D. Central norepinephrine transmission is required for stress-induced repetitive behavior in two rodent models of obsessive-compulsive disorder. Psychopharmacology (Berl) 2020; 237:1973-1987. [PMID: 32313981 PMCID: PMC7961804 DOI: 10.1007/s00213-020-05512-0] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Accepted: 03/26/2020] [Indexed: 02/06/2023]
Abstract
RATIONALE Obsessive-compulsive disorder (OCD) is characterized by repetitive behaviors exacerbated by stress. Many OCD patients do not respond to available pharmacotherapies, but neurosurgical ablation of the anterior cingulate cortex (ACC) can provide symptomatic relief. Although the ACC receives noradrenergic innervation and expresses adrenergic receptors (ARs), the involvement of norepinephrine (NE) in OCD has not been investigated. OBJECTIVE To determine the effects of genetic or pharmacological disruption of NE neurotransmission on marble burying (MB) and nestlet shredding (NS), two animal models of OCD. METHODS We assessed NE-deficient (Dbh -/-) mice and NE-competent (Dbh +/-) controls in MB and NS tasks. We also measured the effects of anti-adrenergic drugs on NS and MB in control mice and the effects of pharmacological restoration of central NE in Dbh -/- mice. Finally, we compared c-fos induction in the locus coeruleus (LC) and ACC of Dbh -/- and control mice following both tasks. RESULTS Dbh -/- mice virtually lacked MB and NS behaviors seen in control mice but did not differ in the elevated zero maze (EZM) model of general anxiety-like behavior. Pharmacological restoration of central NE synthesis in Dbh -/- mice completely rescued NS behavior, while NS and MB were suppressed in control mice by anti-adrenergic drugs. Expression of c-fos in the ACC was attenuated in Dbh -/- mice after MB and NS. CONCLUSION These findings support a role for NE transmission to the ACC in the expression of stress-induced compulsive behaviors and suggest further evaluation of anti-adrenergic drugs for OCD is warranted.
Collapse
Affiliation(s)
- Daniel Lustberg
- Department of Human Genetics, Emory University School of Medicine, 615 Michael St., Whitehead 301, Atlanta, GA, 30322, USA
| | - Alexa F Iannitelli
- Department of Human Genetics, Emory University School of Medicine, 615 Michael St., Whitehead 301, Atlanta, GA, 30322, USA
| | - Rachel P Tillage
- Department of Human Genetics, Emory University School of Medicine, 615 Michael St., Whitehead 301, Atlanta, GA, 30322, USA
| | - Molly Pruitt
- University of Maryland School of Medicine, Baltimore, MD, 21201, USA
| | - L Cameron Liles
- Department of Human Genetics, Emory University School of Medicine, 615 Michael St., Whitehead 301, Atlanta, GA, 30322, USA
| | - David Weinshenker
- Department of Human Genetics, Emory University School of Medicine, 615 Michael St., Whitehead 301, Atlanta, GA, 30322, USA.
| |
Collapse
|
9
|
Stevens L, Vonck K, Larsen LE, Van Lysebettens W, Germonpré C, Baekelandt V, Van den Haute C, Carrette E, Wadman WJ, Boon P, Raedt R. A Feasibility Study to Investigate Chemogenetic Modulation of the Locus Coeruleus by Means of Single Unit Activity. Front Neurosci 2020; 14:162. [PMID: 32210746 PMCID: PMC7067893 DOI: 10.3389/fnins.2020.00162] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Accepted: 02/12/2020] [Indexed: 11/13/2022] Open
Abstract
Aim Selective chemogenetic modulation of locus coeruleus (LC) neurons would allow dedicated investigation of the role of the LC-NA pathway in brain excitability and disorders such as epilepsy. This study investigated the feasibility of an experimental set-up where chemogenetic modification of the brainstem locus coeruleus NA neurons is aimed at and followed by LC unit activity recording in response to clozapine. Methods The LC of male Sprague-Dawley rats was injected with 10 nl of adeno-associated viral vector AAV2/7-PRSx8-hM3Dq-mCherry (n = 19, DREADD group) or AAV2/7-PRSx8-eGFP (n = 13, Controls). Three weeks later, LC unit recordings were performed in anesthetized rats. We investigated whether clozapine, a drug known to bind to modified neurons expressing hM3Dq receptors, was able to increase the LC firing rate. Baseline unit activity was recorded followed by subsequent administration of 0.01 and 0.1 mg/kg of clozapine in all rats. hM3Dq-mcherry expression levels were investigated using immunofluorescence staining of brainstem slices at the end of the experiment. Results Unit recordings could be performed in 12 rats and in a total of 12 neurons (DREADDs: n = 7, controls: n = 5). Clozapine 0.01 mg/kg did not affect the mean firing rate of recorded LC-neurons; 0.1 mg/kg induced an increased firing rate, irrespective whether neurons were recorded from DREADD or control rats (p = 0.006). Co-labeling of LC neurons and mCherry-tag showed that 20.6 ± 2.3% LC neurons expressed the hM3Dq receptor. Aspecific expression of hM3Dq-mCherry was also observed in non-LC neurons (26.0 ± 4.1%). Conclusion LC unit recording is feasible in an experimental set-up following manipulations for DREADD induction. A relatively low transduction efficiency of the used AAV was found. In view of this finding, the effect of injected clozapine on LC-NA could not be investigated as a reliable outcome parameter for activation of chemogenetically modified LC neurons. The use of AAV2/7, a vector previously applied successfully to target dopaminergic neurons in the substantia nigra, leads to insufficient chemogenetic modification of the LC compared to transduction with AAV2/9.
Collapse
Affiliation(s)
- Latoya Stevens
- 4BRAIN, Institute for Neuroscience, Department of Neurology, Ghent University, Ghent, Belgium
| | - Kristl Vonck
- 4BRAIN, Institute for Neuroscience, Department of Neurology, Ghent University, Ghent, Belgium
| | - Lars Emil Larsen
- 4BRAIN, Institute for Neuroscience, Department of Neurology, Ghent University, Ghent, Belgium
| | - Wouter Van Lysebettens
- 4BRAIN, Institute for Neuroscience, Department of Neurology, Ghent University, Ghent, Belgium
| | - Charlotte Germonpré
- 4BRAIN, Institute for Neuroscience, Department of Neurology, Ghent University, Ghent, Belgium
| | - Veerle Baekelandt
- Laboratory for Neurobiology and Gene Therapy, Center for Molecular Medicine, Leuven Brain Institute, KU Leuven, Leuven, Belgium
| | - Chris Van den Haute
- Laboratory for Neurobiology and Gene Therapy, Center for Molecular Medicine, Leuven Brain Institute, KU Leuven, Leuven, Belgium.,Leuven Viral Vector Core, Centre for Molecular Medicine, KU Leuven, Leuven, Belgium
| | - Evelien Carrette
- 4BRAIN, Institute for Neuroscience, Department of Neurology, Ghent University, Ghent, Belgium
| | - Wytse Jan Wadman
- 4BRAIN, Institute for Neuroscience, Department of Neurology, Ghent University, Ghent, Belgium
| | - Paul Boon
- 4BRAIN, Institute for Neuroscience, Department of Neurology, Ghent University, Ghent, Belgium
| | - Robrecht Raedt
- 4BRAIN, Institute for Neuroscience, Department of Neurology, Ghent University, Ghent, Belgium
| |
Collapse
|
10
|
Ebrahimzadeh M, El Mansari M, Blier P. Synergistic effect of aripiprazole and escitalopram in increasing serotonin but not norepinephrine neurotransmission in the rat hippocampus. Neuropharmacology 2019; 146:12-18. [DOI: 10.1016/j.neuropharm.2018.11.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2018] [Revised: 10/31/2018] [Accepted: 11/05/2018] [Indexed: 12/28/2022]
|
11
|
Maroteaux L, Béchade C, Roumier A. Dimers of serotonin receptors: Impact on ligand affinity and signaling. Biochimie 2019; 161:23-33. [PMID: 30685449 DOI: 10.1016/j.biochi.2019.01.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Accepted: 01/16/2019] [Indexed: 01/03/2023]
Abstract
Membrane receptors often form complexes with other membrane proteins that directly interact with different effectors of the signal transduction machinery. G-protein-coupled receptors (GPCRs) were for long time considered as single pharmacological entities. However, evidence for oligomerization appeared for various classes and subtypes of GPCRs. This review focuses on metabotropic serotonin (5-hydroxytryptamine, 5-HT) receptors, which belong to the rhodopsin-like class A of GPCRs, and will summarize the convergent evidence that homo- and hetero-dimers containing 5-HT receptors exist in transfected cells and in-vivo. We will show that complexes involving 5-HT receptors may acquire new signal transduction pathways and new physiological roles. In some cases, these complexes participate in disease-specific deregulations, that can be differentially affected by various drugs. Hence, selecting receptor complex-specific responses of these heterodimers may constitute an emerging strategy likely to improve beneficial therapeutic effects.
Collapse
Affiliation(s)
- Luc Maroteaux
- INSERM UMR-S839, S1270, Paris, 75005, France; Sorbonne Université, Paris, 75005, France; Institut du Fer à Moulin, Paris, 75005, France.
| | - Catherine Béchade
- INSERM UMR-S839, S1270, Paris, 75005, France; Sorbonne Université, Paris, 75005, France; Institut du Fer à Moulin, Paris, 75005, France
| | - Anne Roumier
- INSERM UMR-S839, S1270, Paris, 75005, France; Sorbonne Université, Paris, 75005, France; Institut du Fer à Moulin, Paris, 75005, France
| |
Collapse
|
12
|
Szabadi E. Functional Organization of the Sympathetic Pathways Controlling the Pupil: Light-Inhibited and Light-Stimulated Pathways. Front Neurol 2018; 9:1069. [PMID: 30619035 PMCID: PMC6305320 DOI: 10.3389/fneur.2018.01069] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Accepted: 11/23/2018] [Indexed: 11/13/2022] Open
Abstract
Pupil dilation is mediated by a sympathetic output acting in opposition to parasympathetically mediated pupil constriction. While light stimulates the parasympathetic output, giving rise to the light reflex, it can both inhibit and stimulate the sympathetic output. Light-inhibited sympathetic pathways originate in retina-receptive neurones of the pretectum and the suprachiasmatic nucleus (SCN): by attenuating sympathetic activity, they allow unimpeded operation of the light reflex. Light stimulates the noradrenergic and serotonergic pathways. The hub of the noradrenergic pathway is the locus coeruleus (LC) containing both excitatory sympathetic premotor neurones (SympPN) projecting to preganglionic neurones in the spinal cord, and inhibitory parasympathetic premotor neurones (ParaPN) projecting to preganglionic neurones in the Edinger-Westphal nucleus (EWN). SympPN receive inputs from the SCN via the dorsomedial hypothalamus, orexinergic neurones of the latero-posterior hypothalamus, wake- and sleep-promoting neurones of the hypothalamus and brain stem, nociceptive collaterals of the spinothalamic tract, whereas ParaPN receive inputs from the amygdala, sleep/arousal network, nociceptive spinothalamic collaterals. The activity of LC neurones is regulated by inhibitory α2-adrenoceptors. There is a species difference in the function of the preautonomic LC. In diurnal animals, the α2-adrenoceptor agonist clonidine stimulates mainly autoreceptors on SymPN, causing miosis, whereas in nocturnal animals it stimulates postsynaptic α2-arenoceptors in the EWN, causing mydriasis. Noxious stimulation activates SympPN in diurnal animals and ParaPN in nocturnal animals, leading to pupil dilation via sympathoexcitation and parasympathetic inhibition, respectively. These differences may be attributed to increased activity of excitatory LC neurones due to stimulation by light in diurnal animals. This may also underlie the wake-promoting effect of light in diurnal animals, in contrast to its sleep-promoting effect in nocturnal species. The hub of the serotonergic pathway is the dorsal raphe nucleus that is light-sensitive, both directly and indirectly (via an orexinergic input). The light-stimulated pathways mediate a latent mydriatic effect of light on the pupil that can be unmasked by drugs that either inhibit or stimulate SympPN in these pathways. The noradrenergic pathway has widespread connections to neural networks controlling a variety of functions, such as sleep/arousal, pain, and fear/anxiety. Many physiological and psychological variables modulate pupil function via this pathway.
Collapse
Affiliation(s)
- Elemer Szabadi
- Developmental Psychiatry, Queen's Medical Centre, University of Nottingham, Nottingham, United Kingdom
| |
Collapse
|
13
|
Atkin T, Comai S, Gobbi G. Drugs for Insomnia beyond Benzodiazepines: Pharmacology, Clinical Applications, and Discovery. Pharmacol Rev 2018; 70:197-245. [PMID: 29487083 DOI: 10.1124/pr.117.014381] [Citation(s) in RCA: 172] [Impact Index Per Article: 28.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Although the GABAergic benzodiazepines (BZDs) and Z-drugs (zolpidem, zopiclone, and zaleplon) are FDA-approved for insomnia disorders with a strong evidence base, they have many side effects, including cognitive impairment, tolerance, rebound insomnia upon discontinuation, car accidents/falls, abuse, and dependence liability. Consequently, the clinical use of off-label drugs and novel drugs that do not target the GABAergic system is increasing. The purpose of this review is to analyze the neurobiological and clinical evidence of pharmacological treatments of insomnia, excluding the BZDs and Z-drugs. We analyzed the melatonergic agonist drugs, agomelatine, prolonged-release melatonin, ramelteon, and tasimelteon; the dual orexin receptor antagonist suvorexant; the modulators of the α2δ subunit of voltage-sensitive calcium channels, gabapentin and pregabalin; the H1 antagonist, low-dose doxepin; and the histamine and serotonin receptor antagonists, amitriptyline, mirtazapine, trazodone, olanzapine, and quetiapine. The pharmacology and mechanism of action of these treatments and the evidence-base for the use of these drugs in clinical practice is outlined along with novel pipelines. There is evidence to recommend suvorexant and low-dose doxepin for sleep maintenance insomnia; there is also sufficient evidence to recommend ramelteon for sleep onset insomnia. Although there is limited evidence for the use of the quetiapine, trazodone, mirtazapine, amitriptyline, pregabalin, gabapentin, agomelatine, and olanzapine as treatments for insomnia disorder, these drugs may improve sleep while successfully treating comorbid disorders, with a different side effect profile than the BZDs and Z-drugs. The unique mechanism of action of each drug allows for a more personalized and targeted medical management of insomnia.
Collapse
Affiliation(s)
- Tobias Atkin
- Neurobiological Psychiatry Unit, Department of Psychiatry, McGill University Health Center, McGill University, Montreal, Quebec, Canada (T.A., S.C., G.G.); and Division of Neuroscience, San Raffaele Scientific Institute and Vita-Salute University, Milan, Italy (S.C.)
| | - Stefano Comai
- Neurobiological Psychiatry Unit, Department of Psychiatry, McGill University Health Center, McGill University, Montreal, Quebec, Canada (T.A., S.C., G.G.); and Division of Neuroscience, San Raffaele Scientific Institute and Vita-Salute University, Milan, Italy (S.C.)
| | - Gabriella Gobbi
- Neurobiological Psychiatry Unit, Department of Psychiatry, McGill University Health Center, McGill University, Montreal, Quebec, Canada (T.A., S.C., G.G.); and Division of Neuroscience, San Raffaele Scientific Institute and Vita-Salute University, Milan, Italy (S.C.)
| |
Collapse
|
14
|
Szabo ST, Thorpy MJ, Mayer G, Peever JH, Kilduff TS. Neurobiological and immunogenetic aspects of narcolepsy: Implications for pharmacotherapy. Sleep Med Rev 2018; 43:23-36. [PMID: 30503715 DOI: 10.1016/j.smrv.2018.09.006] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Revised: 09/22/2018] [Accepted: 09/27/2018] [Indexed: 01/19/2023]
Abstract
Excessive daytime sleepiness (EDS) and cataplexy are common symptoms of narcolepsy, a sleep disorder associated with the loss of hypocretin/orexin (Hcrt) neurons. Although only a few drugs have received regulatory approval for narcolepsy to date, treatment involves diverse medications that affect multiple biochemical targets and neural circuits. Clinical trials have demonstrated efficacy for the following classes of drugs as narcolepsy treatments: alerting medications (amphetamine, methylphenidate, modafinil/armodafinil, solriamfetol [JZP-110]), antidepressants (tricyclic antidepressants, selective serotonin reuptake inhibitors, serotonin-norepinephrine reuptake inhibitors), sodium oxybate, and the H3-receptor inverse agonist/antagonist pitolisant. Enhanced catecholamine availability and regulation of locus coeruleus (LC) norepinephrine (NE) neuron activity is likely central to the therapeutic activity of most of these compounds. LC NE neurons are integral to sleep/wake regulation and muscle tone; reduced excitatory input to the LC due to compromise of Hcrt/orexin neurons (likely due to autoimmune factors) results in LC NE dysregulation and contributes to narcolepsy/cataplexy symptoms. Agents that increase catecholamines and/or LC activity may mitigate EDS and cataplexy by elevating NE regulation of GABAergic inputs from the amygdala. Consequently, novel medications and treatment strategies aimed at preserving and/or modulating Hcrt/orexin-LC circuit integrity are warranted in narcolepsy/cataplexy.
Collapse
Affiliation(s)
- Steven T Szabo
- Duke University Medical Center, Durham, NC, USA; Durham Veterans Affairs Medical Center, Durham, NC, USA.
| | | | | | - John H Peever
- University of Toronto, Toronto, Ontario M5S 3G5, Canada.
| | - Thomas S Kilduff
- Center for Neuroscience, Biosciences Division, SRI International, Menlo Park, CA 94025, USA.
| |
Collapse
|
15
|
Herman A, El Mansari M, Adham N, Kiss B, Farkas B, Blier P. Involvement of 5-HT 1A and 5-HT 2A Receptors but Not α 2-Adrenoceptors in the Acute Electrophysiological Effects of Cariprazine in the Rat Brain In Vivo. Mol Pharmacol 2018; 94:1363-1370. [PMID: 30322874 DOI: 10.1124/mol.118.113290] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Accepted: 10/04/2018] [Indexed: 11/22/2022] Open
Abstract
Cariprazine, an orally active and potent dopamine D3-preferring D3/D2 receptor partial agonist, is approved to treat adults with schizophrenia (in the United States and Europe) and manic or mixed episodes associated with bipolar I disorder (in the United States). Cariprazine also displays partial agonism at serotonin [5-hydroxytryptamine (5-HT)] 5-HT1A receptors and antagonism at 5-HT2A and 5-HT2B receptors in vitro. The study objective was to determine whether cariprazine leads to functional alterations of monoamine systems in vivo via electrophysiological recordings from anesthetized rats. Dorsal raphe nucleus (DRN), locus coeruleus (LC), and hippocampus pyramidal neurons were recorded, and cariprazine was administered systemically or locally through iontophoresis. In the DRN, cariprazine completely inhibited the firing activity of 5-HT neurons, which was fully reversed by the 5-HT1A receptor antagonist, WAY100635. In the LC, cariprazine reversed the inhibitory effect of the preferential 5-HT2A receptor agonist, 2,5-dimethoxy-4-iodoamphetamine, on norepinephrine (NE) neurons (ED50 = 66 µg/kg) but did not block the inhibitory effect of the α 2-adrenergic receptor agonist, clonidine. Cariprazine, iontophorized into the hippocampus, diminished pyramidal neuronal firing through activation of 5-HT1A receptors, while its concomitant administration did not dampen the suppressant effect of 5-HT. These results indicate that, in vivo, cariprazine acted as a 5-HT1A autoreceptor agonist in the DRN, a 5-HT2A receptor antagonist in modulating the firing activity of LC NE neurons, and a full agonist at 5-HT1A receptors mediating the electrophysiological effect of 5-HT on pyramidal neurons. The modulatory actions of cariprazine on these monoaminergic systems may contribute to its therapeutic effectiveness in patients with depressive episodes.
Collapse
Affiliation(s)
- Anna Herman
- Mood Disorders Research Unit, University of Ottawa Institute of Mental Health Research, Ottawa, Ontario, Canada (A.H., M.E.M., P.B.); Allergan, Madison, New Jersey, United States (N.A.); and Gedeon Richter Plc, Budapest, Hungary (B.K., B.F.)
| | - Mostafa El Mansari
- Mood Disorders Research Unit, University of Ottawa Institute of Mental Health Research, Ottawa, Ontario, Canada (A.H., M.E.M., P.B.); Allergan, Madison, New Jersey, United States (N.A.); and Gedeon Richter Plc, Budapest, Hungary (B.K., B.F.)
| | - Nika Adham
- Mood Disorders Research Unit, University of Ottawa Institute of Mental Health Research, Ottawa, Ontario, Canada (A.H., M.E.M., P.B.); Allergan, Madison, New Jersey, United States (N.A.); and Gedeon Richter Plc, Budapest, Hungary (B.K., B.F.)
| | - Béla Kiss
- Mood Disorders Research Unit, University of Ottawa Institute of Mental Health Research, Ottawa, Ontario, Canada (A.H., M.E.M., P.B.); Allergan, Madison, New Jersey, United States (N.A.); and Gedeon Richter Plc, Budapest, Hungary (B.K., B.F.)
| | - Bence Farkas
- Mood Disorders Research Unit, University of Ottawa Institute of Mental Health Research, Ottawa, Ontario, Canada (A.H., M.E.M., P.B.); Allergan, Madison, New Jersey, United States (N.A.); and Gedeon Richter Plc, Budapest, Hungary (B.K., B.F.)
| | - Pierre Blier
- Mood Disorders Research Unit, University of Ottawa Institute of Mental Health Research, Ottawa, Ontario, Canada (A.H., M.E.M., P.B.); Allergan, Madison, New Jersey, United States (N.A.); and Gedeon Richter Plc, Budapest, Hungary (B.K., B.F.)
| |
Collapse
|
16
|
McMorris T, Barwood M, Corbett J. Central fatigue theory and endurance exercise: Toward an interoceptive model. Neurosci Biobehav Rev 2018; 93:93-107. [DOI: 10.1016/j.neubiorev.2018.03.024] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Revised: 02/15/2018] [Accepted: 03/22/2018] [Indexed: 12/20/2022]
|
17
|
d-Lysergic acid diethylamide, psilocybin, and other classic hallucinogens: Mechanism of action and potential therapeutic applications in mood disorders. PROGRESS IN BRAIN RESEARCH 2018; 242:69-96. [PMID: 30471683 DOI: 10.1016/bs.pbr.2018.07.008] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Depression and anxiety are psychiatric diagnoses commonly associated with low quality of life and low percentage of responsiveness by patients treated with currently available drugs. Thus, research into alternative compounds to treat these disorders is essential to guarantee a patient's remission. The last decade has witnessed a revamped interest for the application of psychedelic medicine for the treatment of mental disorders due to anecdotal reports and clinical studies which show that low doses of d-lysergic acid diethylamide (LSD) and psilocybin may have antidepressant effects. LSD and psilocybin have demonstrated mood-modulating properties likely due to their capacity to modulate serotonergic (5-HT), dopaminergic (DA) and glutamatergic systems. LSD, belonging to the category of "classic halluginogens," interacts with the 5-HT system through 5HT1A, and 5HT2A receptors, with the DA system through D2 receptors, and indirectly also the glutamatergic neurotransmission thought the recruitment of N-methyl-d-aspartate (NMDA) receptors. Randomized clinical studies have confirmed its antidepressant and anxiolytic effects in humans. Thus, in this chapter, we will review the pharmacology of psychedelic drugs, report the most striking clinical evidence which substantiate the therapeutic potentials of these fascinating compounds in mood disorders, and look into the horizon of where psychedelic medicine is heading.
Collapse
|
18
|
Perez-Palomar B, Mollinedo-Gajate I, Berrocoso E, Meana JJ, Ortega JE. Serotonin 5-HT 3 receptor antagonism potentiates the antidepressant activity of citalopram. Neuropharmacology 2018; 133:491-502. [PMID: 29477299 DOI: 10.1016/j.neuropharm.2018.02.020] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2017] [Revised: 01/31/2018] [Accepted: 02/21/2018] [Indexed: 12/16/2022]
Abstract
Activation of serotonin 5-HT3 receptor (5HT3R) in the locus coeruleus (LC), the principal somatodendritic noradrenergic area, decreases LC firing activity and noradrenaline (NA) release in prefrontal cortex (PFC). Blockade of 5HT3R in coadministration with selective serotonin reuptake inhibitors (SSRIs) has been proposed as a potential strategy to accelerate the onset of action of SSRIs. Dual-probe microdialysis in rats was used to evaluate the involvement of 5HT3R in the in vivo effect exerted by the SSRI citalopram on NA release. Besides, forced swimming test (FST) was carried out in mice to evaluate the antidepressant-like effect of citalopram in combination with a 5HT3R antagonist (Y25130). Systemic administration of the 5HT3R agonist SR57227 (10 mg/kg i.p.) increased NA in LC (Emax = 200 ± 27%) and PFC (Emax = 133 ± 2%). The increase in PFC was enhanced in local presence into LC of Y25130 (50 μM) (Emax = 296 ± 41%) suggesting an inhibitory function on NA release exerted by the activation of 5HT3R located in somatodendritic areas. Citalopram administration (10 mg/kg i.p.) increased NA in LC (Emax = 185 ± 11%) and decreased it in PFC (Emax = -35 ± 7%). Intra-LC (50 μM) or systemic co-administration of Y25130 (10 mg/kg i.p.) with citalopram (10 mg/kg i.p.) switched NA release in the PFC from an inhibition to a stimulatory effect. In mice FST, systemic coadministration of citalopram (2.5 mg/kg i.p.) and Y25130 (10 mg/kg i.p.) potentiated the decrease of immobility time through the increase of both swimming and climbing behaviours. These results suggest that the addition of a 5HT3R antagonist to SSRIs could represent a feasible strategy to improve antidepressant response.
Collapse
Affiliation(s)
- Blanca Perez-Palomar
- Department of Pharmacology, University of the Basque Country UPV/EHU, Leioa, Bizkaia, Spain; Centro de Investigación Biomédica en Red de Salud Mental, CIBERSAM, Spain
| | - Irene Mollinedo-Gajate
- Department of Pharmacology, University of the Basque Country UPV/EHU, Leioa, Bizkaia, Spain; Centro de Investigación Biomédica en Red de Salud Mental, CIBERSAM, Spain
| | - Esther Berrocoso
- Centro de Investigación Biomédica en Red de Salud Mental, CIBERSAM, Spain; Neuropsychopharmacology and Psychobiology Research Group, Department of Psychology, University of Cádiz, Cádiz, Spain
| | - J Javier Meana
- Department of Pharmacology, University of the Basque Country UPV/EHU, Leioa, Bizkaia, Spain; Centro de Investigación Biomédica en Red de Salud Mental, CIBERSAM, Spain; Biocruces Health Research Institute, Spain
| | - Jorge E Ortega
- Department of Pharmacology, University of the Basque Country UPV/EHU, Leioa, Bizkaia, Spain; Centro de Investigación Biomédica en Red de Salud Mental, CIBERSAM, Spain; Biocruces Health Research Institute, Spain.
| |
Collapse
|
19
|
Partial inhibition of catecholamine activity and enhanced responsiveness to NMDA after sustained administration of vortioxetine. Neuropharmacology 2018; 128:425-432. [DOI: 10.1016/j.neuropharm.2017.10.036] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Revised: 10/26/2017] [Accepted: 10/28/2017] [Indexed: 12/20/2022]
|
20
|
Moutkine I, Quentin E, Guiard BP, Maroteaux L, Doly S. Heterodimers of serotonin receptor subtypes 2 are driven by 5-HT 2C protomers. J Biol Chem 2017; 292:6352-6368. [PMID: 28258217 DOI: 10.1074/jbc.m117.779041] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Revised: 03/02/2017] [Indexed: 11/06/2022] Open
Abstract
The serotonin receptor subtypes 2 comprise 5-HT2A, 5-HT2B, and 5-HT2C, which are Gαq-coupled receptors and display distinct pharmacological properties. Although co-expressed in some brain regions and involved in various neurological disorders, their functional interactions have not yet been studied. We report that 5-HT2 receptors can form homo- and heterodimers when expressed alone or co-expressed in transfected cells. Co-immunoprecipitation and bioluminescence resonance energy transfer studies confirmed that 5-HT2C receptors interact with either 5-HT2A or 5-HT2B receptors. Although heterodimerization with 5-HT2C receptors does not alter 5-HT2C Gαq-dependent inositol phosphate signaling, 5-HT2A or 5-HT2B receptor-mediated signaling was totally blunted. This feature can be explained by a dominance of 5-HT2C on 5-HT2A and 5-HT2B receptor binding; in 5-HT2C-containing heterodimers, ligands bind and activate the 5-HT2C protomer exclusively. This dominant effect on the associated protomer was also observed in neurons, supporting the physiological relevance of 5-HT2 receptor heterodimerization in vivo Accordingly, exogenous expression of an inactive form of the 5-HT2C receptor in the locus ceruleus is associated with decreased 5-HT2A-dependent noradrenergic transmission. These data demonstrate that 5-HT2 receptors can form functionally asymmetric heterodimers in vitro and in vivo that must be considered when analyzing the physiological or pathophysiological roles of serotonin in tissues where 5-HT2 receptors are co-expressed.
Collapse
Affiliation(s)
- Imane Moutkine
- From the INSERM UMR-S839, Paris 75005.,the Université Pierre et Marie Curie, Paris 75005.,the Institut du Fer à Moulin, Paris 75005
| | - Emily Quentin
- From the INSERM UMR-S839, Paris 75005.,the Université Pierre et Marie Curie, Paris 75005.,the Institut du Fer à Moulin, Paris 75005
| | - Bruno P Guiard
- the Research Center on Animal Cognition, Center for Integrative Biology, Université Paul Sabatier, UMR5169 CNRS, 118, Route de Narbonne, 31062, Toulouse Cedex 9, France
| | - Luc Maroteaux
- From the INSERM UMR-S839, Paris 75005, .,the Université Pierre et Marie Curie, Paris 75005.,the Institut du Fer à Moulin, Paris 75005
| | - Stephane Doly
- the Institut Cochin, INSERM U1016, CNRS UMR8104, Paris 75014, .,the Université Paris Descartes, Sorbonne Paris Cité, Paris 75014.,the Université Clermont Auvergne, INSERM, NEURO-DOL, F-63000 Clermont-Ferrand, and
| |
Collapse
|
21
|
Differential behavioral sensitivity to carbon dioxide (CO 2) inhalation in rats. Neuroscience 2017; 346:423-433. [PMID: 28087339 DOI: 10.1016/j.neuroscience.2017.01.003] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Revised: 12/14/2016] [Accepted: 01/03/2017] [Indexed: 01/21/2023]
Abstract
Inhalation of carbon dioxide (CO2) is frequently employed as a biological challenge to evoke intense fear and anxiety. In individuals with panic disorder, CO2 reliably evokes panic attacks. Sensitivity to CO2 is highly heterogeneous among individuals, and although a genetic component is implicated, underlying mechanisms are not clear. Preclinical models that can simulate differential responsivity to CO2 are therefore relevant. In the current study we investigated CO2-evoked behavioral responses in four different rat strains: Sprague-Dawley (SD), Wistar (W), Long Evans (LE) and Wistar-Kyoto, (WK) rats. We also assessed tryptophan hydroxylase 2 (TPH-2)-positive serotonergic neurons in anxiety/panic regulatory subdivisions of the dorsal raphe nucleus (DR), as well as dopamine β hydroxylase (DβH)-positive noradrenergic neurons in the locus coeruleus, implicated in central CO2-chemosensitivity. Behavioral responsivity to CO2 inhalation varied between strains. CO2-evoked immobility was significantly higher in LE and WK rats as compared with W and SD cohorts. Differences were also observed in CO2-evoked rearing and grooming behaviors. Exposure to CO2 did not produce conditioned behavioral responses upon re-exposure to CO2 context in any strain. Reduced TPH-2-positive cell counts were observed specifically in the panic-regulatory dorsal raphe ventrolateral (DRVL)-ventrolateral periaqueductal gray (VLPAG) subdivision in CO2-sensitive strains. Conversely, DβH-positive cell counts within the LC were significantly higher in CO2-sensitive strains. Collectively, our data provide evidence for strain dependent, differential CO2-sensitivity and potential differences in monoaminergic systems regulating panic and anxiety. Comparative studies between CO2-vulnerable and resistant strains may facilitate the mechanistic understanding of differential CO2-sensitivity in the development of panic and anxiety disorders.
Collapse
|
22
|
Fernández-Pastor B, Ortega JE, Grandoso L, Castro E, Ugedo L, Pazos Á, Meana JJ. Chronic citalopram administration desensitizes prefrontal cortex but not somatodendritic α 2-adrenoceptors in rat brain. Neuropharmacology 2016; 114:114-122. [PMID: 27908769 DOI: 10.1016/j.neuropharm.2016.11.025] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Revised: 11/18/2016] [Accepted: 11/26/2016] [Indexed: 12/27/2022]
Abstract
Selective serotonin reuptake inhibitors (SSRIs) regulate brain noradrenergic neurotransmission both at somatodendritic and nerve terminal areas. Previous studies have demonstrated that noradrenaline (NA) reuptake inhibitors are able to desensitize α2-adrenoceptor-mediated responses. The present study was undertaken to elucidate the effects of repeated treatment with the SSRI citalopram on the α2-adrenoceptor sensitivity in locus coeruleus (LC) and prefrontal cortex (PFC), by using in vivo microdialysis and electrophysiological techniques, and in vitro stimulation of [35S]GTPγS binding autoradiography. Repeated, but not acute, treatment with citalopram (5 mg/kg, i.p., 14 days) increased extracellular NA concentration selectively in PFC. The α2-adrenoceptor agonist clonidine (0.3 mg/kg, i.p.), administered to saline-treated animals (1 ml/kg i.p., 14 days) induced NA decrease in LC (Emax = -44 ± 4%; p < 0.001) and in PFC (Emax = -61 ± 5%, p < 0.001). In citalopram chronically-treated rats, clonidine administration exerted a lower decrease of NA (Emax = -25 ± 7%; p < 0.001) in PFC whereas the effect in LC was not different to controls (Emax = -36 ± 4%). Clonidine administration (0.625-20 μg/kg, i.v.) evoked a dose-dependent decrease of the firing activity of LC noradrenergic neurons in both citalopram- (ED50 = 3.2 ± 0.4 μg/kg) and saline-treated groups (ED50 = 2.6 ± 0.5 μg/kg). No significant differences between groups were found in ED50 values. The α2-adrenoceptor agonist UK14304 stimulated specific [35S]GTPγS binding in brain sections containing LC (144 ± 14%) and PFC (194 ± 32%) of saline-treated animals. In citalopram-treated animals, this increase did not differ from controls in LC (146 ± 22%) but was lower in PFC (141 ± 8%; p < 0.05). Taken together, long-term citalopram treatment induces a desensitization of α2-adrenoceptors acting as axon terminal autoreceptors in PFC without changes in somatodendritic α2-adrenoceptor sensitivity.
Collapse
Affiliation(s)
| | - Jorge E Ortega
- Department of Pharmacology, University of the Basque Country UPV/EHU, Leioa, Bizkaia, Spain; Centro de Investigación Biomédica en Red de Salud Mental CIBERSAM, Spain; BioCruces Health Research Institute, Bizkaia, Spain.
| | - Laura Grandoso
- Department of Pharmacology, University of the Basque Country UPV/EHU, Leioa, Bizkaia, Spain
| | - Elena Castro
- Centro de Investigación Biomédica en Red de Salud Mental CIBERSAM, Spain; Department of Physiology and Pharmacology, Institute of Biomedicine & Biotechnology of Cantabria (IBBTEC), University of Cantabria-CSIC-IDICAN, Santander, Cantabria, Spain
| | - Luisa Ugedo
- Department of Pharmacology, University of the Basque Country UPV/EHU, Leioa, Bizkaia, Spain
| | - Ángel Pazos
- Centro de Investigación Biomédica en Red de Salud Mental CIBERSAM, Spain; Department of Physiology and Pharmacology, Institute of Biomedicine & Biotechnology of Cantabria (IBBTEC), University of Cantabria-CSIC-IDICAN, Santander, Cantabria, Spain
| | - J Javier Meana
- Department of Pharmacology, University of the Basque Country UPV/EHU, Leioa, Bizkaia, Spain; Centro de Investigación Biomédica en Red de Salud Mental CIBERSAM, Spain; BioCruces Health Research Institute, Bizkaia, Spain
| |
Collapse
|
23
|
Optogenetic Activation of Dorsal Raphe Serotonin Neurons Rapidly Inhibits Spontaneous But Not Odor-Evoked Activity in Olfactory Cortex. J Neurosci 2016; 36:7-18. [PMID: 26740645 DOI: 10.1523/jneurosci.3008-15.2016] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
UNLABELLED Serotonin (5-hydroxytriptamine; 5-HT) is implicated in a variety of brain functions including not only the regulation of mood and control of behavior but also the modulation of perception. 5-HT neurons in the dorsal raphe nucleus (DRN) often fire locked to sensory stimuli, but little is known about how 5-HT affects sensory processing, especially on this timescale. Here, we used an optogenetic approach to study the effect of 5-HT on single-unit activity in the mouse primary olfactory (anterior piriform) cortex. We show that activation of DRN 5-HT neurons rapidly inhibits the spontaneous firing of olfactory cortical neurons, acting in a divisive manner, but entirely spares sensory-driven firing. These results identify a new role for serotonergic modulation in dynamically regulating the balance between different sources of neural activity in sensory systems, suggesting a possible role for 5-HT in perceptual inference. SIGNIFICANCE STATEMENT Serotonin is implicated in a wide variety of (pato)physiological functions including perception, but its precise role has remained elusive. Here, using optogenetic tools in vivo, we show that serotonergic neuromodulation prominently inhibits the spontaneous electrical activity of neurons in the primary olfactory cortex on a rapid (<1 s) timescale but leaves sensory responses unaffected. These results identify a new role for serotonergic modulation in rapidly changing the balance between different sources of neural activity in sensory systems.
Collapse
|
24
|
Kaneko F, Kawahara Y, Kishikawa Y, Hanada Y, Yamada M, Kakuma T, Kawahara H, Nishi A. Long-Term Citalopram Treatment Alters the Stress Responses of the Cortical Dopamine and Noradrenaline Systems: the Role of Cortical 5-HT1A Receptors. Int J Neuropsychopharmacol 2016; 19:pyw026. [PMID: 27029212 PMCID: PMC5006198 DOI: 10.1093/ijnp/pyw026] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/15/2015] [Accepted: 03/23/2016] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND Cortical dopamine and noradrenaline are involved in the stress response. Citalopram, a selective serotonin reuptake inhibitor, has direct and indirect effects on the serotonergic system. Furthermore, long-term treatment with citalopram affects the dopamine and noradrenaline systems, which could contribute to the therapeutic action of antidepressants. METHODS The effects of long-term treatment with citalopram on the responses of the dopamine and noradrenaline systems in the rat prefrontal cortex to acute handling stress were evaluated using in vivo microdialysis. RESULTS Acute handling stress increased dopamine and noradrenaline levels in the prefrontal cortex. The dopamine and noradrenaline responses were suppressed by local infusion of a 5-HT1A receptor agonist, 7-(Dipropylamino)-5,6,7,8-tetrahydronaphthalen-1-ol;hydrobromide, into the prefrontal cortex. The dopamine response was abolished by long-term treatment with citalopram, and the abolished dopamine response was reversed by local infusion of a 5-HT1A receptor antagonist, (Z)-but-2-enedioic acid;N-[2-[4-(2-methoxyphenyl)piperazin-1-yl]ethyl]-N-pyridin-2-ylcyclohexanecarboxamide into the prefrontal cortex. On the other hand, long-term treatment with citalopram reduced the basal noradrenaline levels (approximately 40% of the controls), but not the basal dopamine levels. The noradrenaline response was maintained despite the low basal noradrenaline levels. Signaling from the 5-HT1A receptors and α2-adrenoceptors was not involved in the decrease in the basal noradrenaline levels but partially affected the noradrenaline response. CONCLUSIONS Chronic citalopram treatment differentially suppresses the dopamine and noradrenaline systems in the prefrontal cortex, and the dopamine stress response was preferentially controlled by upregulating 5-HT1A receptor signaling. Our findings provide insight into how antidepressants modulate the dopamine and noradrenaline systems to overcome acute stress.
Collapse
Affiliation(s)
| | - Yukie Kawahara
- Department of Pharmacology, Kurume University School of Medicine, Kurume, Fukuoka, Japan (Ms Kaneko and Drs Kawahara, Kishikawa, Hanada, and Nishi); Department of Psychiatry, Tokyo Women's Medical University, Shinjuku-ku, Tokyo, Japan (Dr Yamada); Biostatistics Center, Kurume University, Kurume, Fukuoka, Japan (Dr Kakuma); Department of Dental Anesthesiology, School of Dentistry, Tsurumi University, Tsurumi-ku, Yokohama, Kanagawa, Japan (Dr Kawahara).
| | | | | | | | | | | | | |
Collapse
|
25
|
Long-term administration of the antidepressant vilazodone modulates rat brain monoaminergic systems. Neuropharmacology 2015; 99:696-704. [DOI: 10.1016/j.neuropharm.2015.09.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2015] [Revised: 08/26/2015] [Accepted: 09/05/2015] [Indexed: 11/23/2022]
|
26
|
Spain A, Howarth C, Khrapitchev AA, Sharp T, Sibson NR, Martin C. Neurovascular and neuroimaging effects of the hallucinogenic serotonin receptor agonist psilocin in the rat brain. Neuropharmacology 2015; 99:210-20. [PMID: 26192543 PMCID: PMC4655865 DOI: 10.1016/j.neuropharm.2015.07.018] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Revised: 06/22/2015] [Accepted: 07/16/2015] [Indexed: 12/28/2022]
Abstract
The development of pharmacological magnetic resonance imaging (phMRI) has presented the opportunity for investigation of the neurophysiological effects of drugs in vivo. Psilocin, a hallucinogen metabolised from psilocybin, was recently reported to evoke brain region-specific, phMRI signal changes in humans. The present study investigated the effects of psilocin in a rat model using phMRI and then probed the relationship between neuronal and haemodynamic responses using a multimodal measurement preparation. Psilocin (2 mg/kg or 0.03 mg/kg i.v.) or vehicle was administered to rats (N=6/group) during either phMRI scanning or concurrent imaging of cortical blood flow and recording of local field potentials. Compared to vehicle controls psilocin (2 mg/kg) evoked phMRI signal increases in a number of regions including olfactory and limbic areas and elements of the visual system. PhMRI signal decreases were seen in other regions including somatosensory and motor cortices. Investigation of neurovascular coupling revealed that whilst neuronal responses (local field potentials) to sensory stimuli were decreased in amplitude by psilocin administration, concurrently measured haemodynamic responses (cerebral blood flow) were enhanced. The present findings show that psilocin evoked region-specific changes in phMRI signals in the rat, confirming recent human data. However, the results also suggest that the haemodynamic signal changes underlying phMRI responses reflect changes in both neuronal activity and neurovascular coupling. This highlights the importance of understanding the neurovascular effects of pharmacological manipulations for interpreting haemodynamic neuroimaging data.
Collapse
Affiliation(s)
- Aisling Spain
- Department of Psychology, University of Sheffield, Western Bank, Sheffield S10 2TP, UK; Cancer Research UK & Medical Research Council Oxford Institute for Radiation Oncology, Department of Oncology, University of Oxford, Oxford OX3 7DQ, UK.
| | - Clare Howarth
- Department of Psychology, University of Sheffield, Western Bank, Sheffield S10 2TP, UK; Cancer Research UK & Medical Research Council Oxford Institute for Radiation Oncology, Department of Oncology, University of Oxford, Oxford OX3 7DQ, UK.
| | - Alexandre A Khrapitchev
- Cancer Research UK & Medical Research Council Oxford Institute for Radiation Oncology, Department of Oncology, University of Oxford, Oxford OX3 7DQ, UK.
| | - Trevor Sharp
- Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, UK.
| | - Nicola R Sibson
- Cancer Research UK & Medical Research Council Oxford Institute for Radiation Oncology, Department of Oncology, University of Oxford, Oxford OX3 7DQ, UK.
| | - Chris Martin
- Department of Psychology, University of Sheffield, Western Bank, Sheffield S10 2TP, UK.
| |
Collapse
|
27
|
Oosterhof CA, El Mansari M, Bundgaard C, Blier P. Brexpiprazole Alters Monoaminergic Systems following Repeated Administration: an in Vivo Electrophysiological Study. Int J Neuropsychopharmacol 2015; 19:pyv111. [PMID: 26428352 PMCID: PMC4815476 DOI: 10.1093/ijnp/pyv111] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Accepted: 09/24/2015] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Brexpiprazole was recently approved as adjunctive therapy for depression and treatment of schizophrenia in adults. To complement results from a previous study in which its acute effects were characterized, the present study assessed the effect of repeated brexpiprazole administration on monoaminergic systems. METHODS Brexpiprazole (1mg/kg, subcutaneous) or vehicle was administered once daily for 2 and 14 days. Single-unit electrophysiological recordings from noradrenaline neurons in the locus coeruleus, serotonin neurons in the dorsal raphe nucleus, dopaminergic neurons in the ventral tegmental area, and pyramidal neurons in the hippocampus CA3 region were obtained in adult male Sprague-Dawley rats under chloral hydrate anesthesia within 4 hours after final dosing. RESULTS Brexpiprazole blunted D2 autoreceptor responsiveness, while firing activity of ventral tegmental area dopaminergic neurons remained unaltered. Brexpiprazole increased the firing rate of locus coeruleus noradrenaline neurons and increased noradrenaline tone on α2-adrenergic receptors in the hippocampus. Administration of brexpiprazole for 2 but not 14 days increased the firing rate of serotonin neurons in the dorsal raphe nucleus. In the hippocampus, serotonin1A receptor blockade significantly disinhibited pyramidal neurons after 2- and 14-day brexpiprazole administration. In contrast, no significant disinhibition occurred after 24-hour washout or acute brexpiprazole. CONCLUSIONS Repeated brexpiprazole administration resulted in a marked occupancy of D2 autoreceptors, while discharge activity of ventral tegmental area dopaminergic neurons remained unaltered. Brexpiprazole enhanced serotonergic and noradrenergic tone in the hippocampus, effects common to antidepressant agents. Together, these results provide further insight in the neural mechanisms by which brexpiprazole exerts antidepressant and antipsychotic effects.
Collapse
Affiliation(s)
- Chris A Oosterhof
- Institute of Mental Health Research (Dr Oosterhof, Dr El Mansari, and Dr Blier), and Department of Cellular and Molecular Medicine (Dr Oosterhof and Dr Blier), University of Ottawa, Ottawa, Ontario, Canada; Neuroscience Drug Discovery, H. Lundbeck A/S, Valby, Denmark (Dr Bundgaard).
| | - Mostafa El Mansari
- Institute of Mental Health Research (Dr Oosterhof, Dr El Mansari, and Dr Blier), and Department of Cellular and Molecular Medicine (Dr Oosterhof and Dr Blier), University of Ottawa, Ottawa, Ontario, Canada; Neuroscience Drug Discovery, H. Lundbeck A/S, Valby, Denmark (Dr Bundgaard)
| | - Christoffer Bundgaard
- Institute of Mental Health Research (Dr Oosterhof, Dr El Mansari, and Dr Blier), and Department of Cellular and Molecular Medicine (Dr Oosterhof and Dr Blier), University of Ottawa, Ottawa, Ontario, Canada; Neuroscience Drug Discovery, H. Lundbeck A/S, Valby, Denmark (Dr Bundgaard)
| | - Pierre Blier
- Institute of Mental Health Research (Dr Oosterhof, Dr El Mansari, and Dr Blier), and Department of Cellular and Molecular Medicine (Dr Oosterhof and Dr Blier), University of Ottawa, Ottawa, Ontario, Canada; Neuroscience Drug Discovery, H. Lundbeck A/S, Valby, Denmark (Dr Bundgaard)
| |
Collapse
|
28
|
Carli M, Kostoula C, Sacchetti G, Mainolfi P, Anastasia A, Villani C, Invernizzi RW. Tph2 gene deletion enhances amphetamine-induced hypermotility: effect of 5-HT restoration and role of striatal noradrenaline release. J Neurochem 2015; 135:674-85. [DOI: 10.1111/jnc.13280] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2015] [Revised: 07/29/2015] [Accepted: 07/30/2015] [Indexed: 11/30/2022]
Affiliation(s)
- Mirjana Carli
- Department of Neuroscience; IRCCS - Istituto di Ricerche Farmacologiche “Mario Negri”; Lab. Neurochemistry and Behavior; Milano Italy
| | - Chrysaugi Kostoula
- Department of Neuroscience; IRCCS - Istituto di Ricerche Farmacologiche “Mario Negri”; Lab. Neurochemistry and Behavior; Milano Italy
| | - Giuseppina Sacchetti
- Department of Neuroscience; IRCCS - Istituto di Ricerche Farmacologiche “Mario Negri”; Lab. Neurochemistry and Behavior; Milano Italy
| | - Pierangela Mainolfi
- Department of Neuroscience; IRCCS - Istituto di Ricerche Farmacologiche “Mario Negri”; Lab. Neurochemistry and Behavior; Milano Italy
| | - Alessia Anastasia
- Department of Neuroscience; IRCCS - Istituto di Ricerche Farmacologiche “Mario Negri”; Lab. Neurochemistry and Behavior; Milano Italy
| | - Claudia Villani
- Department of Neuroscience; IRCCS - Istituto di Ricerche Farmacologiche “Mario Negri”; Lab. Neurochemistry and Behavior; Milano Italy
| | - Roberto William Invernizzi
- Department of Neuroscience; IRCCS - Istituto di Ricerche Farmacologiche “Mario Negri”; Lab. Neurochemistry and Behavior; Milano Italy
| |
Collapse
|
29
|
Asenapine alters the activity of monoaminergic systems following its subacute and long-term administration: an in vivo electrophysiological characterization. Eur Neuropsychopharmacol 2015; 25:531-43. [PMID: 25656272 DOI: 10.1016/j.euroneuro.2015.01.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2014] [Revised: 12/22/2014] [Accepted: 01/09/2015] [Indexed: 11/24/2022]
Abstract
Asenapine is a tetracyclic atypical antipsychotic used for treatment of schizophrenia and mania. Previous in vivo electrophysiological studies demonstrated antagonistic action of asenapine at dopamine D2, serotonin (5-HT)2A, and α2-adrenergic receptors. Here, we assessed monoamine system activities after two-day and 21-day asenapine administration at a dosage (0.1mg/kg/day) resulting in clinically relevant plasma levels. In the ventral tegmental area (VTA), asenapine increased the number of spontaneously active dopamine neurons, while firing parameters remained unchanged. Asenapine partially prevented the D2 autoreceptor-mediated inhibitory response to apomorphine after two days of administration. This effect was lost after 21 days of administration, suggesting adaptive changes leading to D2 receptor sensitization. Asenapine increased the firing activity of noradrenergic neurons in the locus coeruleus (LC) after 21, but not two days of administration. Furthermore, it potently blocked 5-HT2A receptors while α2-adrenergic receptors were unaffected by this drug regimen. Both acute and long-term asenapine administration partially blocked α2-adrenergic receptors in the CA3 region of the hippocampus, and noradrenergic tone on α1- and α2-adrenoceptors remained unchanged. In the dorsal raphe nucleus, asenapine increased the firing rate of 5-HT neurons after two, but not 21 days of administration. In addition, responsiveness of 5-HT1A autoreceptors was unaltered by asenapine. In the hippocampus, 21-day asenapine administration increased serotonergic tone by partial agonistic action on postsynaptic 5-HT1A and terminal 5-HT1B receptors. Taken together, asenapine had profound effects on both catecholamine systems, potently blocked 5-HT2A receptors, and enhanced 5-HT tone, effects that could be important in treatment of mood disorders and schizophrenia.
Collapse
|
30
|
Guiard BP, Di Giovanni G. Central serotonin-2A (5-HT2A) receptor dysfunction in depression and epilepsy: the missing link? Front Pharmacol 2015; 6:46. [PMID: 25852551 PMCID: PMC4362472 DOI: 10.3389/fphar.2015.00046] [Citation(s) in RCA: 82] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2015] [Accepted: 02/24/2015] [Indexed: 11/17/2022] Open
Abstract
5-Hydroxytryptamine 2A receptors (5-HT2A-Rs) are G-protein coupled receptors. In agreement with their location in the brain, they have been implicated not only in various central physiological functions including memory, sleep, nociception, eating and reward behaviors, but also in many neuropsychiatric disorders. Interestingly, a bidirectional link between depression and epilepsy is suspected since patients with depression and especially suicide attempters have an increased seizure risk, while a significant percentage of epileptic patients suffer from depression. Such epidemiological data led us to hypothesize that both pathologies may share common anatomical and neurobiological alteration of the 5-HT2A signaling. After a brief presentation of the pharmacological properties of the 5-HT2A-Rs, this review illustrates how these receptors may directly or indirectly control neuronal excitability in most networks involved in depression and epilepsy through interactions with the monoaminergic, GABAergic and glutamatergic neurotransmissions. It also synthetizes the preclinical and clinical evidence demonstrating the role of these receptors in antidepressant and antiepileptic responses.
Collapse
Affiliation(s)
- Bruno P Guiard
- CNRS, Centre de Recherches sur la Cognition Animale, UMR 5169, Toulouse France ; CNRS, Centre de Recherches sur la Cognition Animale Université de Toulouse 3, UMR 5169, Toulouse, France ; INSERM U1178 Team ≪Depression and Antidepressants≫ Faculté de Pharmacie Paris Sud, Châtenay-Malabry, France
| | - Giuseppe Di Giovanni
- Neurophysiology Unit, Laboratory for the Study of Neurological Disorders, Department of Physiology and Biochemistry, University of Malta, Msida Malta ; School of Biosciences, University of Cardiff, Cardiff UK
| |
Collapse
|
31
|
Halberstadt AL. Recent advances in the neuropsychopharmacology of serotonergic hallucinogens. Behav Brain Res 2015; 277:99-120. [PMID: 25036425 PMCID: PMC4642895 DOI: 10.1016/j.bbr.2014.07.016] [Citation(s) in RCA: 189] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2014] [Revised: 07/07/2014] [Accepted: 07/08/2014] [Indexed: 12/12/2022]
Abstract
Serotonergic hallucinogens, such as (+)-lysergic acid diethylamide, psilocybin, and mescaline, are somewhat enigmatic substances. Although these drugs are derived from multiple chemical families, they all produce remarkably similar effects in animals and humans, and they show cross-tolerance. This article reviews the evidence demonstrating the serotonin 5-HT2A receptor is the primary site of hallucinogen action. The 5-HT2A receptor is responsible for mediating the effects of hallucinogens in human subjects, as well as in animal behavioral paradigms such as drug discrimination, head twitch response, prepulse inhibition of startle, exploratory behavior, and interval timing. Many recent clinical trials have yielded important new findings regarding the psychopharmacology of these substances. Furthermore, the use of modern imaging and electrophysiological techniques is beginning to help unravel how hallucinogens work in the brain. Evidence is also emerging that hallucinogens may possess therapeutic efficacy.
Collapse
Affiliation(s)
- Adam L Halberstadt
- Department of Psychiatry, University of California San Diego, La Jolla, CA, United States.
| |
Collapse
|
32
|
Oosterhof CA, El Mansari M, Blier P. Acute Effects of Brexpiprazole on Serotonin, Dopamine, and Norepinephrine Systems: An In Vivo Electrophysiologic Characterization. J Pharmacol Exp Ther 2014; 351:585-95. [DOI: 10.1124/jpet.114.218578] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
|
33
|
de Carvalho D, Patrone LGA, Taxini CL, Biancardi V, Vicente MC, Gargaglioni LH. Neurochemical and electrical modulation of the locus coeruleus: contribution to CO2drive to breathe. Front Physiol 2014; 5:288. [PMID: 25183958 PMCID: PMC4135231 DOI: 10.3389/fphys.2014.00288] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2014] [Accepted: 07/14/2014] [Indexed: 11/13/2022] Open
Abstract
The locus coeruleus (LC) is a dorsal pontine region, situated bilaterally on the floor of the fourth ventricle. It is considered to be the major source of noradrenergic innervation in the brain. These neurons are highly sensitive to CO2/pH, and chemical lesions of LC neurons largely attenuate the hypercapnic ventilatory response in unanesthetized adult rats. Developmental dysfunctions in these neurons are linked to pathological conditions such as Rett and sudden infant death syndromes, which can impair the control of the cardio-respiratory system. LC is densely innervated by fibers that contain glutamate, serotonin, and adenosine triphosphate, and these neurotransmitters strongly affect LC activity, including central chemoreflexes. Aside from neurochemical modulation, LC neurons are also strongly electrically coupled, specifically through gap junctions, which play a role in the CO2 ventilatory response. This article reviews the available data on the role of chemical and electrical neuromodulation of the LC in the control of ventilation.
Collapse
Affiliation(s)
- Débora de Carvalho
- Department of Animal Morphology and Physiology, Faculty of Agricultural and Veterinarian Sciences, Universidade Estadual Paulista - São Paulo State University Jaboticabal, Brazil
| | - Luis G A Patrone
- Department of Animal Morphology and Physiology, Faculty of Agricultural and Veterinarian Sciences, Universidade Estadual Paulista - São Paulo State University Jaboticabal, Brazil
| | - Camila L Taxini
- Department of Animal Morphology and Physiology, Faculty of Agricultural and Veterinarian Sciences, Universidade Estadual Paulista - São Paulo State University Jaboticabal, Brazil
| | - Vivian Biancardi
- Department of Animal Morphology and Physiology, Faculty of Agricultural and Veterinarian Sciences, Universidade Estadual Paulista - São Paulo State University Jaboticabal, Brazil
| | - Mariane C Vicente
- Department of Animal Morphology and Physiology, Faculty of Agricultural and Veterinarian Sciences, Universidade Estadual Paulista - São Paulo State University Jaboticabal, Brazil
| | - Luciane H Gargaglioni
- Department of Animal Morphology and Physiology, Faculty of Agricultural and Veterinarian Sciences, Universidade Estadual Paulista - São Paulo State University Jaboticabal, Brazil
| |
Collapse
|
34
|
Repeated exposure to MDMA triggers long-term plasticity of noradrenergic and serotonergic neurons. Mol Psychiatry 2014; 19:823-33. [PMID: 23958955 DOI: 10.1038/mp.2013.97] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2012] [Revised: 06/28/2013] [Accepted: 07/10/2013] [Indexed: 11/08/2022]
Abstract
3,4-Methylenedioxymethamphetamine (MDMA or 'ecstasy') is a psychostimulant drug, widely used recreationally among young people in Europe and North America. Although its neurotoxicity has been extensively described, little is known about its ability to strengthen neural circuits when administered in a manner that reproduces human abuse (i.e. repeated exposure to a low dose). C57BL/6J mice were repeatedly injected with MDMA (10 mg kg(-1), intraperitoneally) and studied after a 4-day or a 1-month withdrawal. We show, using in vivo microdialysis and locomotor activity monitoring, that repeated injections of MDMA induce a long-term sensitization of noradrenergic and serotonergic neurons, which correlates with behavioral sensitization. The development of this phenomenon, which lasts for at least 1 month after withdrawal, requires repeated stimulation of α(1B)-adrenergic and 5-hydroxytryptamine (5-HT)(2A) receptors. Moreover, behavioral and neuroendocrine assays indicate that hyper-reactivity of noradrenergic and serotonergic networks is associated with a persistent desensitization of somatodendritic α(2A)-adrenergic and 5-HT1A autoreceptor function. Finally, molecular analysis including radiolabeling, western blot and quantitative reverse transcription-polymerase chain reaction reveals that mice repeatedly treated with MDMA exhibit normal α(2A)-adrenergic and 5-HT(1A) receptor binding, but a long-lasting downregulation of Gαi proteins expression in both locus coeruleus and dorsal raphe nucleus. Altogether, our results show that repeated MDMA exposure causes strong neural and behavioral adaptations and that inhibitory feedback mediated by α(2A)-adrenergic and 5-HT(1A) autoreceptors has an important role in the physiopathology of addictive behaviors.
Collapse
|
35
|
Chronic nandrolone decanoate exposure during adolescence affects emotional behavior and monoaminergic neurotransmission in adulthood. Neuropharmacology 2014; 83:79-88. [PMID: 24721625 DOI: 10.1016/j.neuropharm.2014.03.015] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2013] [Revised: 03/25/2014] [Accepted: 03/30/2014] [Indexed: 12/14/2022]
Abstract
Nandrolone decanoate, an anabolic androgen steroid (AAS) illicitly used by adult and adolescent athletes to enhance physical performance and body image, induces psychiatric side effects, such as aggression, depression as well as a spectrum of adverse physiological impairments. Since adolescence represents a neurodevelopmental window that is extremely sensitive to the detrimental effects of drug abuse, we investigated the long-term behavioral and neurophysiological consequences of nandrolone abuse during adolescence. Adolescent rats received daily injections of nandrolone decanoate (15 mg/kg, i.m.) for 14 days (PND 40-53). At early adulthood (PND 68), forced swim, sucrose preference, open field and elevated plus maze tests were performed to assess behavioral changes. In vivo electrophysiological recordings were carried out to monitor changes in electrical activity of serotonergic neurons of the dorsal raphe nucleus (DRN) and noradrenergic neurons of the locus coeruleus (LC). Our results show that after early exposure to nandrolone, rats display depression-related behavior, characterized by increased immobility in the forced swim test and reduced sucrose intake in the sucrose preference test. In addition, adult rats presented anxiety-like behavior characterized by decreased time and number of entries in the central zone of the open field and decreased time spent in the open arms of the elevated plus maze. Nandrolone decreased the firing rate of spontaneously active serotonergic neurons in the DRN while increasing the firing rate of noradrenergic neurons in the LC. These results provide evidence that nandrolone decanoate exposure during adolescence alters the emotional profile of animals in adulthood and significantly modifies both serotonergic and noradrenergic neurotransmission.
Collapse
|
36
|
Nguyen HT, Guiard BP, Bacq A, David DJ, David I, Quesseveur G, Gautron S, Sanchez C, Gardier AM. Blockade of the high-affinity noradrenaline transporter (NET) by the selective 5-HT reuptake inhibitor escitalopram: an in vivo microdialysis study in mice. Br J Pharmacol 2014; 168:103-16. [PMID: 22233336 DOI: 10.1111/j.1476-5381.2012.01850.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
BACKGROUND AND PURPOSE Escitalopram, the S(+)-enantiomer of citalopram is the most selective 5-HT reuptake inhibitor approved. Although all 5-HT selective reuptake inhibitors (SSRIs) increase extracellular levels of 5-HT ([5-HT](ext)). some also enhance, to a lesser extent, extracellular levels of noradrenaline ([NA](ext)). However, the mechanisms by which SSRIs activate noradrenergic transmission in the brain remain to be determined. EXPERIMENTAL APPROACH This study examined the effects of escitalopram, on both [5-HT](ext) and [NA](ext) in the frontal cortex (FCx) of freely moving wild-type (WT) and mutant mice lacking the 5-HT transporter (SERT(-/-)) by using intracerebral microdialysis. We explored the possibilities that escitalopram enhances [NA](ext), either by a direct mechanism involving the inhibition of the low- or high-affinity noradrenaline transporters, or by an indirect mechanism promoted by [5-HT](ext) elevation. The forced swim test (FST) was used to investigate whether enhancing cortical [5-HT](ext) and/or [NA](ext) affected the antidepressant-like activity of escitalopram. KEY RESULTS In WT mice, a single systemic administration of escitalopram produced a significant increase in cortical [5-HT](ext) and [NA](ext). As expected, escitalopram failed to increase cortical [5-HT](ext) in SERT(-/-) mice, whereas its neurochemical effects on [NA](ext) persisted in these mutants. In WT mice subjected to the FST, escitalopram increased swimming parameters without affecting climbing behaviour. Finally, escitalopram, at relevant concentrations, failed to inhibit cortical noradrenaline and 5-HT uptake mediated by low-affinity monoamine transporters. CONCLUSIONS AND IMPLICATIONS These experiments suggest that escitalopram enhances, although moderately, cortical [NA](ext) in vivo by a direct mechanism involving the inhibition of the high-affinity noradrenaline transporter (NET).
Collapse
Affiliation(s)
- Hai T Nguyen
- Laboratoire de Neuropharmacologie, Faculté de Pharmacie, Université Paris-Sud XI, Châtenay-Malabry, France
| | | | | | | | | | | | | | | | | |
Collapse
|
37
|
Brain neuronal activation induced by flibanserin treatment in female rats. Psychopharmacology (Berl) 2013; 230:639-52. [PMID: 23857113 DOI: 10.1007/s00213-013-3194-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/03/2013] [Accepted: 06/17/2013] [Indexed: 12/19/2022]
Abstract
RATIONALE Flibanserin, a 5-HT1A agonist and 5-HT2A antagonist, is developed for the treatment of hypoactive sexual desire disorder in women, and its efficacy has been evidenced in several clinical studies. Flibanserin prosexual effects have been also evidenced in preclinical animal models. However, the mechanism of action of flibanserin remains not fully understood. OBJECTIVE The aim of the present study was to examine brain neuronal activation in female rats treated with flibanserin, using single immunocytochemical labeling of Fos protein, a marker of neuronal activation, and co-localization of Fos and catecholaminergic marker. METHOD Six groups of female rats received either acute or chronic administrations of vehicle, flibanserin 15 mg/kg or flibanserin 45 mg/kg. The brains were collected and processed for immunocytochemical labeling. RESULTS Acute flibanserin increased levels of Fos immunoreactivity in the nucleus accumbens, arcuate hypothalamic nucleus, locus coeruleus, lateral paragigantocellular nucleus, and nucleus of the solitary tract. Chronic 22-day treatment with flibanserin increased Fos expression in the medial preoptic area and arcuate nucleus of the hypothalamus, ventral tegmental area, locus coeruleus, and lateral paragigantocellular nucleus. Both acute and chronic flibanserin increased the density of activated catecholaminergic neurons in the ventral tegmental area but not in the locus coeruleus. CONCLUSION Altogether, our results showed that flibanserin, at the dose known to enhance female sexual motivation, preferentially activated the brain regions belonging to the mesolimbic dopaminergic pathway and hypothalamic structures involved in the integration of sexual cues related to sexual motivation.
Collapse
|
38
|
Involvement of serotonin 5-HT3 receptors in the modulation of noradrenergic transmission by serotonin reuptake inhibitors: a microdialysis study in rat brain. Psychopharmacology (Berl) 2013; 229:331-44. [PMID: 23636303 DOI: 10.1007/s00213-013-3112-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/15/2012] [Accepted: 04/08/2013] [Indexed: 10/26/2022]
Abstract
RATIONALE Selective serotonin reuptake inhibitors (SSRIs), in addition to being able to enhance serotonergic neurotransmission, are able to modulate other brain systems involved in depression. OBJECTIVES This study evaluates the neurochemical effect of the SSRI citalopram on brain noradrenergic activity and the serotonin receptor involved in this effect. METHODS Dual-probe microdialysis in the locus coeruleus (LC) and prefrontal cortex (PFC) was performed in freely awake rats. RESULTS Systemic citalopram (10 mg/kg, i.p.) increased noradrenaline (NA) in the LC (E max = 141 ± 13%) and simultaneously decreased NA in the PFC (Emax = -46 ± 7%). In the local presence into the LC of the α2-adrenoceptor antagonist RS79948 (1 μM), systemic citalopram increased NA in the LC (Emax = 157 ± 25%) and PFC (Emax = 175 ± 24%). Local citalopram (0.1-100 μM) into the LC induced NA increase in the LC (Emax = 210 ± 25%) and decrease in the PFC (Emax = -38 ± 9%). Local LC citalopram effect was abolished by LC presence of the 5-HT3 receptor antagonist MDL72222 (1 μM) but not the 5-HT1/2 receptor antagonist methiothepin (1 μM). Systemic citalopram in the LC presence of MDL72222 did not modify NA in the LC but increased NA in the PFC (Emax = 158 ± 26%). Local citalopram into the PFC enhanced NA (Emax = 376 ± 18%) in the area, which was prevented by MDL72222. CONCLUSIONS The SSRI citalopram modulates central noradrenergic neurotransmission by activation, through endogenous serotonin, of 5-HT3 receptors expressed in the somatodendritic (LC) and terminal (PFC) areas, which subsequently promote an enhancement of local NA. Therefore, 5-HT3 receptors and somatodendritic α2-adrenoceptors in the LC play an important role in the global effect of SSRIs.
Collapse
|
39
|
Aripiprazole: a dopamine modulator that mimics methylphenidate in producing faster antidepressant effects. Med Hypotheses 2013; 81:183-5. [PMID: 23751312 DOI: 10.1016/j.mehy.2013.05.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2013] [Accepted: 05/15/2013] [Indexed: 11/20/2022]
Abstract
Up to 60% of depressed patients do not respond to two months of pharmacotherapy, and late treatment responses are often correlated with poor outcomes and may be characterized as treatment-resistant depression (TRD). Previous studies have noted that the addition of a psychostimulant such as methylphenidate to the therapeutic regimen of patients with TRD or those depressed patients with comorbid fatigue, advanced age, or a major medical illness showed significant improvement within two weeks. One explanation for the benefit of methylphenidate in treating TRD is that it enhances the level of dopamine in the brain. Adjunctive low dose aripiprazole in patients with TRD has also become a common intervention. Several studies have focused on aripiprazole's pharmacodynamic and pharmacokinetic profiles, but no definitive comments on its antidepressant effects. We hypothesize that a low dose of aripiprazole might play a role as a dopamine agonist similar to that of methylphenidate due to its partial dopamine D2 agonist and 30% intrinsic dopaminergic activity. In addition to its use in patients with TRD, adjunctive aripiprazole might work like methylphenidate in those depressed patients with fatigue, advanced age, or major illnesses. A new drug invention which combined an antidepressant with an adequate dose of aripiprazole should be considered. The neurobiological basis for this combination in treating TRD awaits further study.
Collapse
|
40
|
Role of GIRK channels on the noradrenergic transmission in vivo: an electrophysiological and neurochemical study on GIRK2 mutant mice. Int J Neuropsychopharmacol 2013; 16:1093-104. [PMID: 23040084 DOI: 10.1017/s1461145712000971] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Dysfunctional noradrenergic transmission is related to several neuropsychiatric conditions, such as depression. Nowadays, the role of G protein-coupled inwardly rectifying potassium (GIRK)2 subunit containing GIRK channels controlling neuronal intrinsic excitability in vitro is well known. The aim of this study was to investigate the impact of GIRK2 subunit mutation on the central noradrenergic transmission in vivo. For that purpose, single-unit extracellular activity of locus coeruleus (LC) noradrenergic neurons and brain monoamine levels using the HPLC technique were measured in wild-type and GIRK2 mutant mice. Girk2 gene mutation induced significant differences among genotypes regarding burst activity of LC neurons. In fact, the proportion of neurons displaying burst firing was increased in GIRK2 heterozygous mice as compared to that recorded from wild-type mice. Furthermore, this augmentation was even greater in the homozygous genotype. However, neither the basal firing rate nor the coefficient of variation of LC neurons was different among genotypes. Noradrenaline and serotonin basal levels were altered in the dorsal raphe nucleus from GIRK2 heterozygous and homozygous mice, respectively. Furthermore, noradrenaline levels were increased in LC projecting areas such as the hippocampus and amygdale from homozygous mice, although not in the prefrontal cortex. Finally, potency of clonidine and morphine inhibiting LC activity was reduced in GIRK2 mutant mice, although the efficacy remained unchanged. Altogether, the present study supports the role of GIRK2 subunit-containing GIRK channels on the maintenance of tonic noradrenergic activity in vivo. Electric and neurochemical consequences derived from an altered GIRK2-dependent signalling could facilitate the understanding of the neurobiological basis of pathologies related to a dysfunctional monoaminergic transmission.
Collapse
|
41
|
Stewart AM, Cachat J, Gaikwad S, Robinson KS, Gebhardt M, Kalueff AV. Perspectives on experimental models of serotonin syndrome in zebrafish. Neurochem Int 2013; 62:893-902. [DOI: 10.1016/j.neuint.2013.02.018] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2013] [Revised: 02/10/2013] [Accepted: 02/14/2013] [Indexed: 01/07/2023]
|
42
|
Quesseveur G, Repérant C, David DJ, Gardier AM, Sanchez C, Guiard BP. 5-HT2A receptor inactivation potentiates the acute antidepressant-like activity of escitalopram: involvement of the noradrenergic system. Exp Brain Res 2013; 226:285-95. [DOI: 10.1007/s00221-013-3434-3] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2012] [Accepted: 01/25/2013] [Indexed: 11/30/2022]
|
43
|
Chenu F, El Mansari M, Blier P. Electrophysiological effects of repeated administration of agomelatine on the dopamine, norepinephrine, and serotonin systems in the rat brain. Neuropsychopharmacology 2013; 38:275-84. [PMID: 22871919 PMCID: PMC3527117 DOI: 10.1038/npp.2012.140] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Agomelatine is a melatonergic MT1/MT2 agonist and a serotonin (5-HT) 5-HT(2C) antagonist. The effects of 2-day and 14-day administration of agomelatine were investigated on the activity of ventral tegmental area (VTA) dopamine (DA), locus coeruleus (LC) norepinephrine (NE), and dorsal raphe nucleus (DRN) 5-HT neurons using in vivo electrophysiology in rats. The 5-HT(1A) transmission was assessed at hippocampus CA3 pyramidal neurons. After a 2-day regimen of agomelatine (40 mg/kg/day, i.p.), an increase in the number of spontaneously active VTA-DA neurons (p<0.001) and in the firing rate of LC-NE neurons (p<0.001) was observed. After 14 days, the administration of agomelatine induced an increase in: (1) the number of spontaneously active DA neurons (p<0.05), (2) the bursting activity of DA neurons (bursts/min, p<0.01 and percentage of spikes occurring in bursts, p<0.05), (3) the firing rate of DRN-5-HT neurons (p<0.05), and (4) the tonic activation of postsynaptic 5-HT(1A) receptors located in the hippocampus. The increase in 5-HT firing rate was D2 dependent, as it was antagonized by the D2 receptor antagonist paliperidone. The enhancement of NE firing was restored by the 5-HT(2A) receptor antagonist MDL-100,907 after the 14-day regimen. All the effects of agomelatine were antagonized by a single administration of the melatonergic antagonist S22153 (except for the increase in the percentage of spikes occurring in burst for DA neurons). The present results suggest that (1) agomelatine exerts direct (2 days) and indirect (14 days) modulations of monoaminergic neuronal activity and (2) the melatonergic agonistic activity of agomelatine contributes to the enhancement of DA and 5-HT neurotransmission.
Collapse
Affiliation(s)
- Franck Chenu
- Institute of Mental Health Research, University of Ottawa, Ottawa, ON, Canada
| | - Mostafa El Mansari
- Institute of Mental Health Research, University of Ottawa, Ottawa, ON, Canada
| | - Pierre Blier
- Institute of Mental Health Research, University of Ottawa, Ottawa, ON, Canada,Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, Canada,Institute of Mental Health Research (IMHR), 1145 Carling Avenue, University of Ottawa, Room 6412, Ottawa K1Z 7K4, ON, Canada, Tel: +1 613 722 6521 (ext 6944), Fax: +1 613 761 3610, E-mail:
| |
Collapse
|
44
|
Quesseveur G, Nguyen HT, Gardier AM, Guiard BP. 5-HT2 ligands in the treatment of anxiety and depression. Expert Opin Investig Drugs 2012; 21:1701-25. [PMID: 22917059 DOI: 10.1517/13543784.2012.719872] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
INTRODUCTION One third of depressed patients do not respond adequately to conventional antidepressants including the selective serotonin reuptake inhibitors (SSRIs). Therefore, multi-target drugs or augmentation strategies have been developed for the management of SSRIs-resistant patients. In this context, the 5-HT(2) receptor subtypes represent promising targets but their precise roles have yet to be determined. AREAS COVERED The aim of this review is to shed some light on the preclinical evidence supporting the use of 5-HT(2A) and/or 5-HT(2C) receptor antagonists such as antipsychotics, as potential effective adjuncts in SSRIs-resistant depression. This review synthesizes the current literature about the behavioral, electrophysiological and neurochemical effects of 5-HT(2) receptors ligands on the monoaminergic systems but also on adult hippocampal neurogenesis. EXPERT OPINION Although studies support the hypothesis that the inactivation of 5-HT(2A) and/or 5-HT(2C) receptors might be of interest to reinforce different facets of the therapeutic activity of SSRIs, this pharmacological strategy remains debatable notably because of the lack of chronic data in relevant animal models. Conversely, emerging evidence suggests that the activation of 5-HT(2B) receptor is required for antidepressant-like activity, opening the way to new therapeutic approaches. However, the potential risks related to the enhancement of monoaminergic neurotransmissions could represent a major concern.
Collapse
Affiliation(s)
- Gaël Quesseveur
- EA3544 University Paris-XI, Laboratoire de Neuropharmacologie, Fac. Pharmacie, F-92296, Châtenay-Malabry cedex, France
| | | | | | | |
Collapse
|
45
|
Effect of paroxetine and bupropion on human resting brain perfusion: An arterial spin labeling study. Neuroimage 2012; 61:773-9. [DOI: 10.1016/j.neuroimage.2012.03.014] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2011] [Revised: 02/25/2012] [Accepted: 03/05/2012] [Indexed: 10/28/2022] Open
|
46
|
Ortega JE, Mendiguren A, Pineda J, Meana JJ. Regulation of central noradrenergic activity by 5-HT3 receptors located in the locus coeruleus of the rat. Neuropharmacology 2012; 62:2472-9. [DOI: 10.1016/j.neuropharm.2012.02.018] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2011] [Revised: 02/20/2012] [Accepted: 02/21/2012] [Indexed: 10/28/2022]
|
47
|
Baisley SK, Fallace KL, Rajbhandari AK, Bakshi VP. Mutual independence of 5-HT(2) and α1 noradrenergic receptors in mediating deficits in sensorimotor gating. Psychopharmacology (Berl) 2012; 220:465-79. [PMID: 21947334 PMCID: PMC4090044 DOI: 10.1007/s00213-011-2490-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2011] [Accepted: 09/05/2011] [Indexed: 12/20/2022]
Abstract
RATIONALE Prepulse inhibition (PPI), a preattentional information-filtering mechanism, is disrupted by serotonin (5-HT) or norepinephrine (NE) agonists to model deficits seen in schizophrenia, but whether this effect occurs through interactions between these systems is not known. OBJECTIVES These studies investigated whether PPI/activity changes induced by agonists of one system were dependent on neurotransmission within the other. METHODS Male Sprague-Dawley rats received the 5-HT(2) receptor agonist DOI (1-[2,5-dimethoxy-4-iodophenyl]-2-aminopropane) (0, 0.3 mg/kg), with or without antagonists for α1 (prazosin:0, 0.3, or 1 mg/kg) or β (timolol:0, 3, or 10 mg/kg) receptors or their combination (0 or 0.3 mg/kg prazosin + 3 mg/kg timolol), or the 5-HT(2) antagonist ritanserin (0, 2 mg/kg). Separately, the α1-adrenergic receptor agonist cirazoline (0, 0.68 mg/kg) was given with and without ritanserin (0, 0.5, or 2 mg/kg) or the NE antagonists (0 or 0.3 mg/kg prazosin + 3 mg/kg timolol). Finally, combinations of subthreshold doses of DOI (0, 0.01, 0.025 mg/kg) and cirazoline (0, 0.1, 0.25 mg/kg) were tested for their ability to disrupt PPI, and concomitant administration of all three antagonists (0 vs. 0.3 mg/kg prazosin + 3 mg/kg timolol + 2 mg/kg ritanserin) was assessed for its ability to modify PPI. Locomotion was assessed in an additional set of experiments. RESULTS Doses/combinations of prazosin and timolol that reversed cirazoline-induced effects did not alter DOI-induced effects, and ritanserin did not affect cirazoline at doses that blocked DOI-mediated effects. Concomitant antagonism of α1 + β + 5-HT(2) receptors did not modify PPI, nor did combinations of subthreshold doses of cirazoline and DOI. CONCLUSIONS 5-HT(2) receptors and α1 and β NE receptors may act through independent mechanisms to modulate sensorimotor gating and locomotor activity.
Collapse
Affiliation(s)
- Sarah K. Baisley
- Department of Psychiatry, UW-Madison, Madison, WI, USA,Neuroscience Training Program, UW-Madison, Madison, WI, USA
| | | | - Abha K. Rajbhandari
- Department of Psychiatry, UW-Madison, Madison, WI, USA,Neuroscience Training Program, UW-Madison, Madison, WI, USA
| | - Vaishali P. Bakshi
- Department of Psychiatry, UW-Madison, Madison, WI, USA,Neuroscience Training Program, UW-Madison, Madison, WI, USA,Department of Psychiatry, University of Wisconsin School of Medicine and Public Health, 6001 Research Park Blvd, Madison, WI 53719, USA
| |
Collapse
|
48
|
Locus coeruleus and dorsal raphe neuron activity and response to acute antidepressant administration in a rat model of Parkinson's disease. Int J Neuropsychopharmacol 2011; 14:187-200. [PMID: 20426885 DOI: 10.1017/s146114571000043x] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
In addition to noradrenergic and serotonergic systems, dopaminergic neurotransmission seems to play an important role in the aetiopathogenesis of, and recovery from, depression. Moreover, the incidence of depression is higher in patients affected by diseases where the dopaminergic system is highly impaired, such us Parkinson's disease. Here, we investigated the effects of dopamine degeneration on the activity and response to antidepressants of locus coeruleus (LC) noradrenergic and dorsal raphe nucleus (DRN) serotonergic neurons. To this end, single-unit extracellular recordings were performed in control and 6-hydroxydopamine (6-OHDA)-lesioned animals. In this latter group, LC neurons showed a lower basal firing rate as well as less sensitivity to the administration of the serotonin reuptake inhibitor, fluoxetine. The rest of electrophysiological parameters and the response to the administration of the α2-adrenoceptor agonist, clonidine and the noradrenaline reuptake inhibitor, reboxetine remained unaltered. In the DRN, dopamine depletion did not modify the basal electrophysiological characteristics and the response to clonidine or fluoxetine administration. In contrast, the administration of reboxetine more efficiently induced an inhibitory effect in the lesioned group. In additional analyses it was observed that while in control animals, LC and DRN basal firing rate was significantly correlated, this relationship was lost after the 6-OHDA lesion. In conclusion, dopaminergic degeneration alters LC neuron basal activity, the relationship/synteny between both nuclei, and their response to antidepressants. These findings shed fresh light on our understanding of the role of dopamine in depression and the mechanism action of antidepressants.
Collapse
|
49
|
Haenisch B, Bönisch H. Depression and antidepressants: Insights from knockout of dopamine, serotonin or noradrenaline re-uptake transporters. Pharmacol Ther 2011; 129:352-68. [DOI: 10.1016/j.pharmthera.2010.12.002] [Citation(s) in RCA: 143] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2010] [Accepted: 11/29/2010] [Indexed: 12/15/2022]
|
50
|
Meeusen R, Roelands B. Central fatigue and neurotransmitters, can thermoregulation be manipulated? Scand J Med Sci Sports 2011; 20 Suppl 3:19-28. [PMID: 21029187 DOI: 10.1111/j.1600-0838.2010.01205.x] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Fatigue is a complex phenomenon that can be evoked by peripheral and central factors. Although it is obvious that fatigue has peripheral causes such as glycogen depletion and cardiovascular strain, recent literature also focuses on the central origin of fatigue. It is clear that different brain neurotransmitters--such as serotonin, dopamine and noradrenaline--are implicated in the occurrence of fatigue, but manipulation of these neurotransmitters produced no conclusive results on performance in normal ambient temperature. Exercise in the heat not only adds an extra challenge to the cardiorespiratory system, but also to the brain. This provides a useful tool to investigate the association between exercise-induced hyperthermia and central fatigue. This review focuses on the effects of pharmacological manipulations on performance and thermoregulation in different ambient temperatures. Dopaminergic reuptake inhibition appears to counteract hyperthermia-induced fatigue in 30 °C, while noradrenergic neurotransmission shows negative effects on performance in both normal and high temperature, and serotonergic manipulations did not lead to significant changes in performance. It is, however, unlikely that one neurotransmitter system is responsible for the delay or onset of fatigue. Further research is required to determine the exact mechanisms of fatigue in different environmental conditions.
Collapse
Affiliation(s)
- R Meeusen
- Department of Human Physiology & Sports Medicine, Faculty of Physical Education and Physiotherapy, Vrije Universiteit Brussel, Brussels, Belgium.
| | | |
Collapse
|