1
|
Chestnykh D, Graßl F, Pfeifer C, Dülk J, Ebner C, Walters M, von Hörsten S, Kornhuber J, Kalinichenko LS, Heinrich M, Müller CP. Behavioural effects of APH199, a selective dopamine D4 receptor agonist, in animal models. Psychopharmacology (Berl) 2023; 240:1011-1031. [PMID: 36854793 PMCID: PMC10006056 DOI: 10.1007/s00213-023-06347-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Accepted: 02/21/2023] [Indexed: 03/02/2023]
Abstract
RATIONALE The dopamine D4 receptors (DRD4) play a key role in numerous brain functions and are involved in the pathogenesis of various psychiatric disorders. DRD4 ligands have been shown to moderate anxiety, reward and depression-like behaviours, and cognitive impairments. Despite a series of promising but ambiguous findings, the therapeutic advantages of DRD4 stimulation remain elusive. OBJECTIVES The investigation focused on the behavioural effects of the recently developed DRD4 agonist, APH199, to evaluate its impact on anxiety, anhedonia, behavioural despair, establishment and retrieval of alcohol reinforcement, and amphetamine (AMPH)-induced symptoms. METHODS Male C57BL/6 J mice and Sprague-Dawley rats were examined in five independent experiments. We assessed APH199 (0.1-5 mg/kg, i.p.) effects on a broad range of behavioural parameters in the open field (OF) test, conditioned place preference test (CPP), elevated plus maze (EPM), light-dark box (LDB), novelty suppressed feeding (NSF), forced swim test (FST), sucrose preference test (SPT), AMPH-induced hyperlocomotion test (AIH), and prepulse inhibition (PPI) of the acoustic startle response in AMPH-sensitized rats. RESULTS APH199 caused mild and sporadic anxiolytic and antidepressant effects in EPM and FST, but no remarkable impact on behaviour in other tests in mice. However, we found a significant increase in AMPH-induced hyperactivity, suggesting an exaggeration of the psychotic-like responses in the AMPH-sensitized rats. CONCLUSIONS Our data challenged the hypothesis of the therapeutic benefits of DRD4 agonists, pointing out a possible aggravation of psychosis. We suggest a need for further preclinical studies to ensure the safety of antipsychotics with DRD4 stimulating properties.
Collapse
Affiliation(s)
- Daria Chestnykh
- Department of Psychiatry and Psychotherapy, University Clinic, Friedrich-Alexander-University of Erlangen-Nuremberg, Schwabachanlage 6, 91054, Erlangen, Germany
| | - Fabian Graßl
- Department of Chemistry and Pharmacy, Friedrich-Alexander-University of Erlangen-Nuremberg, Nikolaus-Fiebiger-Str. 10, 91058, Erlangen, Germany
| | - Canice Pfeifer
- Department of Psychiatry and Psychotherapy, University Clinic, Friedrich-Alexander-University of Erlangen-Nuremberg, Schwabachanlage 6, 91054, Erlangen, Germany
| | - Jonas Dülk
- Department of Psychiatry and Psychotherapy, University Clinic, Friedrich-Alexander-University of Erlangen-Nuremberg, Schwabachanlage 6, 91054, Erlangen, Germany
| | - Chiara Ebner
- Department of Psychiatry and Psychotherapy, University Clinic, Friedrich-Alexander-University of Erlangen-Nuremberg, Schwabachanlage 6, 91054, Erlangen, Germany
| | - Mona Walters
- Department of Psychiatry and Psychotherapy, University Clinic, Friedrich-Alexander-University of Erlangen-Nuremberg, Schwabachanlage 6, 91054, Erlangen, Germany
| | - Stephan von Hörsten
- Department of Experimental Therapy, Preclinical Experimental Center, Friedrich-Alexander-University of Erlangen-Nuremberg, Palmsanlage 5, 91054, Erlangen, Germany
| | - Johannes Kornhuber
- Department of Psychiatry and Psychotherapy, University Clinic, Friedrich-Alexander-University of Erlangen-Nuremberg, Schwabachanlage 6, 91054, Erlangen, Germany
| | - Liubov S Kalinichenko
- Department of Psychiatry and Psychotherapy, University Clinic, Friedrich-Alexander-University of Erlangen-Nuremberg, Schwabachanlage 6, 91054, Erlangen, Germany
| | - Markus Heinrich
- Department of Chemistry and Pharmacy, Friedrich-Alexander-University of Erlangen-Nuremberg, Nikolaus-Fiebiger-Str. 10, 91058, Erlangen, Germany
| | - Christian P Müller
- Department of Psychiatry and Psychotherapy, University Clinic, Friedrich-Alexander-University of Erlangen-Nuremberg, Schwabachanlage 6, 91054, Erlangen, Germany.
- Centre for Drug Research, University Sains Malaysia, Penang, Minden, Malaysia.
| |
Collapse
|
2
|
Müller CP. Serotonin and Consciousness-A Reappraisal. Behav Brain Res 2022; 432:113970. [PMID: 35716774 DOI: 10.1016/j.bbr.2022.113970] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Revised: 06/01/2022] [Accepted: 06/06/2022] [Indexed: 11/02/2022]
Abstract
The serotonergic system of the brain is a major modulator of behaviour. Here we describe a re-appraisal of its function for consciousness based on anatomical, functional and pharmacological data. For a better understanding, the current model of consciousness is expanded. Two parallel streams of conscious flow are distinguished. A flow of conscious content and an affective consciousness flow. While conscious content flow has its functional equivalent in the activity of higher cortico-cortical and cortico-thalamic networks, affective conscious flow originates in segregated deeper brain structures for single emotions. It is hypothesized that single emotional networks converge on serotonergic and other modulatory transmitter neurons in the brainstem where a bound percept of an affective conscious flow is formed. This is then dispersed to cortical and thalamic networks, where it is time locked with conscious content flow at the level of these networks. Serotonin acts in concert with other modulatory systems of the brain stem with some possible specialization on single emotions. Together, these systems signal a bound percept of affective conscious flow. Dysfunctions in the serotonergic system may not only give rise to behavioural and somatic symptoms, but also essentially affect the coupling of conscious affective flow with conscious content flow, leading to the affect-stained subjective side of mental disorders like anxiety, depression, or schizophrenia. The present model is an attempt to integrate the growing insights into serotonergic system function. However, it is acknowledged, that several key claims are still at a heuristic level that need further empirical support.
Collapse
Affiliation(s)
- Christian P Müller
- Department of Psychiatry and Psychotherapy, University Clinic, Friedrich-Alexander-Universität Erlangen-Nürnberg, Schwabachanlage 6, 91054, Erlangen, Germany; Centre for Drug Research, Universiti Sains Malaysia, 11800 Minden, Penang, Malaysia.
| |
Collapse
|
3
|
Varga TG, de Toledo Simões JG, Siena A, Henrique E, da Silva RCB, Dos Santos Bioni V, Ramos AC, Rosenstock TR. Haloperidol rescues the schizophrenia-like phenotype in adulthood after rotenone administration in neonatal rats. Psychopharmacology (Berl) 2021; 238:2569-2585. [PMID: 34089344 DOI: 10.1007/s00213-021-05880-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Accepted: 05/20/2021] [Indexed: 10/21/2022]
Abstract
Neuropsychiatric disorders are multifactorial disturbances that encompass several hypotheses, including changes in neurodevelopment. It is known that brain development disturbances during early life can predict psychosis in adulthood. As we have previously demonstrated, rotenone, a mitochondrial complex I inhibitor, could induce psychiatric-like behavior in 60-day-old rats after intraperitoneal injections from the 5th to the 11th postnatal day. Because mitochondrial deregulation is related to psychiatric disorders and the establishment of animal models is a high-value preclinical tool, we investigated the responsiveness of the rotenone (Rot)-treated newborn rats to pharmacological agents used in clinical practice, haloperidol (Hal), and methylphenidate (MPD). Taken together, our data show that Rot-treated animals exhibit hyperlocomotion, decreased social interaction, and diminished contextual fear conditioning response at P60, consistent with positive, negative, and cognitive deficits of schizophrenia (SZ), respectively, that were reverted by Hal, but not MPD. Rot-treated rodents also display a prodromal-related phenotype at P35. Overall, our results seem to present a new SZ animal model as a consequence of mitochondrial inhibition during a critical neurodevelopmental period. Therefore, our study is crucial not only to elucidate the relevance of mitochondrial function in the etiology of SZ but also to fulfill the need for new and trustworthy experimentation models and, likewise, provide possibilities to new therapeutic avenues for this burdensome disorder.
Collapse
Affiliation(s)
- Thiago Garcia Varga
- Department of Physiological Science, Santa Casa de São Paulo School of Medical Science, São Paulo, Brazil
| | | | - Amanda Siena
- Department of Pharmacology, Institute of Biomedical Science, University of São Paulo, Av. Prof. Lineu Prestes, 1524 - Ed. Biomédicas I, 2º andar, São Paulo, SP, 05508-900, Brazil
| | - Elisandra Henrique
- Department of Physiological Science, Santa Casa de São Paulo School of Medical Science, São Paulo, Brazil
| | | | | | - Aline Camargo Ramos
- Department of Psychiatry, Federal University of São Paulo, São Paulo, Brazil
| | - Tatiana Rosado Rosenstock
- Department of Pharmacology, Institute of Biomedical Science, University of São Paulo, Av. Prof. Lineu Prestes, 1524 - Ed. Biomédicas I, 2º andar, São Paulo, SP, 05508-900, Brazil. .,Institute of Cancer and Genomic Sciences, Institute of Biomedical Research, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK.
| |
Collapse
|
4
|
Chestnykh DA, Amato D, Kornhuber J, Müller CP. Pharmacotherapy of schizophrenia: Mechanisms of antipsychotic accumulation, therapeutic action and failure. Behav Brain Res 2021; 403:113144. [PMID: 33515642 DOI: 10.1016/j.bbr.2021.113144] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 01/21/2021] [Accepted: 01/22/2021] [Indexed: 12/13/2022]
Abstract
Schizophrenia is a multi-dimensional disorder with a complex and mostly unknown etiology, leading to a severe decline in life quality. Antipsychotic drugs (APDs) remain beneficial interventions in the treatment of the disorder, but vary significantly in binding profile, clinical effects and adverse reactions. The present review summarizes the main principles of APD mechanisms of action with a particular focus on recent findings in APD accumulation and its role in the therapeutic efficacy and treatment failure. High and low doses of APDs were shown to be effective in different dimensions of antipsychotic-like behaviour in rodent models. Efficacy of the APDs correlates with high dopamine D2 receptor occupancy, which occurs quickly after drug administration. However, onset and peak of action are delayed up to several days or weeks. APD accumulation via acidic trapping in synaptic vesicles is considered to underlie the time course of APD action. Use-dependent exocytosis, co-release with dopamine and serotonin and inhibition of ion channels impact on the neuronal transmission and determine effects of APDs. Disruption in accumulating properties leads to diminished APD effects. In addition, long-term APD administration at therapeutic doses leads to treatment failure both in animal models and in humans. APD failure was associated with treatment induced neuroadaptations, including a decline in extracellular dopamine levels, dopamine transporter upregulation, and altered neuronal firing. However, enhanced synaptic vesicle release has also been reported. APD loss of efficacy may be reversed through inhibition of the dopamine transporter or switching the administration regimen from continuous to intermittent. Thus, manipulating the accumulation properties of APDs, changes in the administration regimen and doses, or co-administration with dopamine transporter inhibitors may be considered to yield benefits in the development of new effective strategies in the treatment of schizophrenia.
Collapse
Affiliation(s)
- Daria A Chestnykh
- Department of Psychiatry and Psychotherapy, University Clinic, Friedrich-Alexander-University Erlangen-Nuremberg, Schwabachanlage 6, 91054, Erlangen, Germany
| | - Davide Amato
- Department of Psychiatry and Psychotherapy, University Clinic, Friedrich-Alexander-University Erlangen-Nuremberg, Schwabachanlage 6, 91054, Erlangen, Germany; Department of Neuroscience, Medical University of South Carolina, Charleston, SC, USA
| | - Johannes Kornhuber
- Department of Psychiatry and Psychotherapy, University Clinic, Friedrich-Alexander-University Erlangen-Nuremberg, Schwabachanlage 6, 91054, Erlangen, Germany
| | - Christian P Müller
- Department of Psychiatry and Psychotherapy, University Clinic, Friedrich-Alexander-University Erlangen-Nuremberg, Schwabachanlage 6, 91054, Erlangen, Germany.
| |
Collapse
|
5
|
Uzuneser TC, Weiss EM, Dahlmanns J, Kalinichenko LS, Amato D, Kornhuber J, Alzheimer C, Hellmann J, Kaindl J, Hübner H, Löber S, Gmeiner P, Grömer TW, Müller CP. Presynaptic vesicular accumulation is required for antipsychotic efficacy in psychotic-like rats. J Psychopharmacol 2021; 35:65-77. [PMID: 33274688 PMCID: PMC7770212 DOI: 10.1177/0269881120965908] [Citation(s) in RCA: 3] [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] [Indexed: 01/11/2023]
Abstract
BACKGROUND The therapeutic effects of antipsychotic drugs (APDs) are mainly attributed to their postsynaptic inhibitory functions on the dopamine D2 receptor, which, however, cannot explain the delayed onset of full therapeutic efficacy. It was previously shown that APDs accumulate in presynaptic vesicles during chronic treatment and are released like neurotransmitters in an activity-dependent manner triggering an auto-inhibitory feedback mechanism. Although closely mirroring therapeutic action onset, the functional consequence of the APD accumulation process remained unclear. AIMS Here we tested whether the accumulation of the APD haloperidol (HAL) is required for full therapeutic action in psychotic-like rats. METHODS We designed a HAL analog compound (HAL-F), which lacks the accumulation property of HAL, but retains its postsynaptic inhibitory action on dopamine D2 receptors. RESULTS/OUTCOMES By perfusing LysoTracker fluorophore-stained cultured hippocampal neurons, we confirmed the accumulation of HAL and the non-accumulation of HAL-F. In an amphetamine hypersensitization psychosis-like model in rats, we found that subchronic intracerebroventricularly delivered HAL (0.1 mg/kg/day), but not HAL-F (0.3-1.5 mg/kg/day), attenuates psychotic-like behavior in rats. CONCLUSIONS/INTERPRETATION These findings suggest the presynaptic accumulation of HAL may serve as an essential prerequisite for its full antipsychotic action and may explain the time course of APD action. Targeting accumulation properties of APDs may, thus, become a new strategy to improve APD action.
Collapse
Affiliation(s)
- Taygun C Uzuneser
- Department of Psychiatry and Psychotherapy, University Clinic, Friedrich-Alexander University of Erlangen-Nuremberg, Erlangen, Germany,Department of Anatomy and Cell Biology, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Canada
| | - Eva-Maria Weiss
- Department of Psychiatry and Psychotherapy, University Clinic, Friedrich-Alexander University of Erlangen-Nuremberg, Erlangen, Germany
| | - Jana Dahlmanns
- Department of Psychiatry and Psychotherapy, University Clinic, Friedrich-Alexander University of Erlangen-Nuremberg, Erlangen, Germany
| | - Liubov S Kalinichenko
- Department of Psychiatry and Psychotherapy, University Clinic, Friedrich-Alexander University of Erlangen-Nuremberg, Erlangen, Germany
| | - Davide Amato
- Department of Psychiatry and Psychotherapy, University Clinic, Friedrich-Alexander University of Erlangen-Nuremberg, Erlangen, Germany,Department of Neuroscience, Medical University of South Carolina, Charleston, USA
| | - Johannes Kornhuber
- Department of Psychiatry and Psychotherapy, University Clinic, Friedrich-Alexander University of Erlangen-Nuremberg, Erlangen, Germany
| | - Christian Alzheimer
- Institute of Physiology and Pathophysiology, Friedrich-Alexander University of Erlangen-Nuremberg, Erlangen, Germany
| | - Jan Hellmann
- Department of Chemistry and Pharmacy, Medicinal Chemistry, Friedrich-Alexander University of Erlangen-Nuremberg, Erlangen, Germany
| | - Jonas Kaindl
- Department of Chemistry and Pharmacy, Medicinal Chemistry, Friedrich-Alexander University of Erlangen-Nuremberg, Erlangen, Germany
| | - Harald Hübner
- Department of Chemistry and Pharmacy, Medicinal Chemistry, Friedrich-Alexander University of Erlangen-Nuremberg, Erlangen, Germany
| | - Stefan Löber
- Department of Chemistry and Pharmacy, Medicinal Chemistry, Friedrich-Alexander University of Erlangen-Nuremberg, Erlangen, Germany
| | - Peter Gmeiner
- Department of Chemistry and Pharmacy, Medicinal Chemistry, Friedrich-Alexander University of Erlangen-Nuremberg, Erlangen, Germany
| | - Teja W Grömer
- Department of Psychiatry and Psychotherapy, University Clinic, Friedrich-Alexander University of Erlangen-Nuremberg, Erlangen, Germany
| | - Christian P Müller
- Department of Psychiatry and Psychotherapy, University Clinic, Friedrich-Alexander University of Erlangen-Nuremberg, Erlangen, Germany,Christian P Müller, Department of Psychiatry and Psychotherapy, University Clinic, Friedrich-Alexander University of Erlangen-Nuremberg, Schwabachanlage 6, Erlangen 91054, Germany.
| |
Collapse
|
6
|
Uzuneser TC, Speidel J, Kogias G, Wang AL, de Souza Silva MA, Huston JP, Zoicas I, von Hörsten S, Kornhuber J, Korth C, Müller CP. Disrupted-in-Schizophrenia 1 (DISC1) Overexpression and Juvenile Immune Activation Cause Sex-Specific Schizophrenia-Related Psychopathology in Rats. Front Psychiatry 2019; 10:222. [PMID: 31057438 PMCID: PMC6465888 DOI: 10.3389/fpsyt.2019.00222] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Accepted: 03/26/2019] [Indexed: 01/12/2023] Open
Abstract
Synaptic pruning is a critical refinement step during neurodevelopment, and schizophrenia has been associated with overpruning of cortical dendritic spines. Both human studies and animal models implicate disrupted-in-schizophrenia 1 (DISC1) gene as a strong susceptibility factor for schizophrenia. Accumulating evidence supports the involvement of DISC1 protein in the modulation of synaptic elimination during critical periods of neurodevelopment and of dopamine D2-receptor-mediated signaling during adulthood. In many species, synaptic pruning occurs during juvenile and adolescent periods and is mediated by microglia, which can be over-activated by an immune challenge, giving rise to overpruning. Therefore, we sought to investigate possible interactions between a transgenic DISC1 model (tgDISC1) and juvenile immune activation (JIA) by the bacterial cell wall endotoxin lipopolysaccharide on the induction of schizophrenia-related behavioral and neurochemical disruptions in adult female and male rats. We examined possible behavioral aberrations along three major symptom dimensions of schizophrenia including psychosis, social and emotional disruptions, and cognitive impairments. We detected significant gene-environment interactions in the amphetamine-induced locomotion in female animals and in the amphetamine-induced anxiety in male animals. Surprisingly, gene-environment interactions improved social memory in both male and female animals. JIA alone disrupted spatial memory and recognition memory, but only in male animals. DISC1 overexpression alone induced an improvement in sensorimotor gating, but only in female animals. Our neurochemical analyses detected sex- and manipulation-dependent changes in the postmortem monoamine content of animals. Taken together, we here report sex-specific effects of environment and genotype as well as their interaction on behavioral phenotypes and neurochemical profiles relevant for schizophrenia.
Collapse
Affiliation(s)
- Taygun C Uzuneser
- Department of Psychiatry and Psychotherapy, University Hospital, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Germany
| | - Jil Speidel
- Department of Psychiatry and Psychotherapy, University Hospital, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Germany
| | - Georgios Kogias
- Department of Psychiatry and Psychotherapy, University Hospital, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Germany
| | - An-Li Wang
- Center for Behavioral Neuroscience, Institute of Experimental Psychology, University of Düsseldorf, Düsseldorf, Germany
| | - Maria A de Souza Silva
- Center for Behavioral Neuroscience, Institute of Experimental Psychology, University of Düsseldorf, Düsseldorf, Germany
| | - Joseph P Huston
- Center for Behavioral Neuroscience, Institute of Experimental Psychology, University of Düsseldorf, Düsseldorf, Germany
| | - Iulia Zoicas
- Department of Psychiatry and Psychotherapy, University Hospital, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Germany
| | - Stephan von Hörsten
- Department of Experimental Therapy, Preclinical Experimental Center, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Germany
| | - Johannes Kornhuber
- Department of Psychiatry and Psychotherapy, University Hospital, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Germany
| | - Carsten Korth
- Department of Neuropathology, Medical Faculty, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - Christian P Müller
- Department of Psychiatry and Psychotherapy, University Hospital, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Germany
| |
Collapse
|
7
|
Groos D, Zheng F, Rauh M, Quinger B, Kornhuber J, Müller CP, Alzheimer C. Chronic antipsychotic treatment targets GIRK current suppression, loss of long-term synaptic depression and behavioural sensitization in a mouse model of amphetamine psychosis. J Psychopharmacol 2018; 33:269881118812235. [PMID: 30488738 DOI: 10.1177/0269881118812235] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
BACKGROUND: Antipsychotic drugs (APDs) are the mainstay of the pharmacological treatment of psychotic disorders like schizophrenia. While the clinical efficacy of APDs has long since been established, the neurobiological mechanisms underlying their therapeutic benefits are still not well understood. METHODS: Here, we used an escalating amphetamine regimen to induce a psychosis-like state in mice. To achieve clinically relevant drug concentrations in amphetamine-pretreated mice, the typical APD haloperidol or the atypical APD olanzapine were chronically administered via subcutaneously implanted osmotic mini-pumps. RESULTS: Demonstrating their therapeutic efficacy, both drugs dampened amphetamine-induced hyperlocomotion and restored normal behaviour in the light-induced activity test. Whole-cell recordings from dopaminergic neurons of the ventral tegmental area (VTA) in ex vivo brain slices revealed two pronounced aberrations associated with the psychosis-like state: Strongly enhanced spontaneous firing and a substantial loss of G protein-gated inwardly rectifying potassium (GIRK) current upon activation of GABAB receptors with baclofen. Chronic haloperidol and olanzapine restored normal firing and partially rescued the GIRK current response to baclofen. In ex vivo slices containing the nucleus accumbens, which receives a dopaminergic projection from the VTA, abrogation of long-term synaptic depression (LTD) and enhanced excitatory drive onto medium spiny neurons were identified as synaptic consequences of amphetamine-induced psychosis. Again, both alterations proved amenable to chronic APD treatment. CONCLUSION: Our data provide evidence for aberrant neuronal function and plasticity in the mesolimbic dopamine system during an induced psychotic state and identify these alterations as targets of chronic APD treatment.
Collapse
Affiliation(s)
- Dominik Groos
- 1 Institute of Physiology and Pathophysiology, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Fang Zheng
- 1 Institute of Physiology and Pathophysiology, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Manfred Rauh
- 2 Department of Pediatrics and Adolescent Medicine, Universitätsklinikum Erlangen, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Benedikt Quinger
- 3 Department of Psychiatry and Psychotherapy, Universitätsklinikum Erlangen, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Johannes Kornhuber
- 3 Department of Psychiatry and Psychotherapy, Universitätsklinikum Erlangen, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Christian P Müller
- 3 Department of Psychiatry and Psychotherapy, Universitätsklinikum Erlangen, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Christian Alzheimer
- 1 Institute of Physiology and Pathophysiology, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| |
Collapse
|