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Luo Y, Li Y, Yuan J. The regulation of the pedunculopontine tegmental nucleus in sleep-wake states. Sleep Biol Rhythms 2024; 22:5-11. [PMID: 38469582 PMCID: PMC10900045 DOI: 10.1007/s41105-023-00489-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Accepted: 09/06/2023] [Indexed: 03/13/2024]
Abstract
The pedunculopontine tegmental nucleus (PPTg) plays a vital role in sleep/wake states. There are three main kinds of heterogeneous neurons involved: cholinergic, glutamatergic, and gamma-aminobutyric acidergic (GABAergic) neurons. However, the precise roles of cholinergic, glutamatergic and GABAergic PPTg cell groups in regulating sleep-wake are unknown. Recent work suggests that the cholinergic, glutamatergic, and GABAergic neurons of the PPTg may activate the main arousal-promoting nucleus, thus exerting their wakefulness effects. We review the related projection pathways and functions of various neurons of the PPTg, especially the mechanisms of the PPTg in sleep-wake, thus providing new perspectives for research of sleep-wake mechanisms.
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Affiliation(s)
- Yiting Luo
- Department of Anesthesiology, The Affiliated Hospital of Zunyi Medical University, No.149 Dalian Road, Huichuan District, Zunyi, 563000 Guizhou China
- Department of Pain Medicine, Affiliated Hospital of Zunyi Medical University, Zunyi, 563000 Guizhou China
| | - Ying Li
- Department of Anesthesiology, The Affiliated Hospital of Zunyi Medical University, No.149 Dalian Road, Huichuan District, Zunyi, 563000 Guizhou China
- Department of Pain Medicine, Affiliated Hospital of Zunyi Medical University, Zunyi, 563000 Guizhou China
| | - Jie Yuan
- Department of Anesthesiology, The Affiliated Hospital of Zunyi Medical University, No.149 Dalian Road, Huichuan District, Zunyi, 563000 Guizhou China
- Department of Pain Medicine, Affiliated Hospital of Zunyi Medical University, Zunyi, 563000 Guizhou China
- Guizhou Key Laboratory of Anesthesia and Organ Protection, Zunyi Medical University, Zunyin, China
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Segal GS, Xie SJ, Paracha SUR, Grossberg GT. Psychosis in Parkinson's Disease: Current Treatment Options and Impact on Patients and Caregivers. J Geriatr Psychiatry Neurol 2021; 34:274-279. [PMID: 34219522 DOI: 10.1177/08919887211018280] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Parkinson's disease (PD) is the second most common neurodegenerative disease seen in older adults after Alzheimer's disease, with increasing prevalence worldwide. Parkinson's disease psychosis (PDP) is a common, non-motor feature of PD, which increases caregiver stress and is a risk-factor for nursing home placement. In this paper we review PDP epidemiology, features, diagnosis, and treatment. PDP most often presents with sequential development of minor and then increasingly complex visual hallucinations mediated by dopaminergic-serotonergic interactions activating the mesolimbic pathway, with contributions from other structures and neurotransmitters. Appropriate evaluation of differential diagnoses for psychosis is vital before diagnosing PDP. Initial treatment should involve non-pharmacologic approaches. If these are unsuccessful and PDP symptoms significantly impact the patient's and or their caregivers' quality of life and functions, then pharmacotherapy is indicated. Pimavanserin is a recently FDA-approved pharmacologic treatment for PDP with a better profile of balanced effectiveness and safety compared to previous use of atypical antipsychotics. Early diagnosis and safer, more effective treatments for PDP should help reduce caregiver burden and enable caregivers to continue to provide care at home versus institutionalization.
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Affiliation(s)
- Gilad S Segal
- 7547Saint Louis University School of Medicine, Saint Louis, MO, USA
| | - Sophie J Xie
- 7547Saint Louis University School of Medicine, Saint Louis, MO, USA
| | - Saif-Ur-Rahman Paracha
- Department of Psychiatry and Behavioral Neuroscience, 7547Saint Louis University School of Medicine, MO, USA
| | - George T Grossberg
- Samuel W. Fordyce Professor and Director of Geriatric Psychiatry, Department of Psychiatry and Behavioral Neuroscience, Saint Louis University School of Medicine, MO, USA
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Cortical and Thalamic Interaction with Amygdala-to-Accumbens Synapses. J Neurosci 2020; 40:7119-7132. [PMID: 32763909 DOI: 10.1523/jneurosci.1121-20.2020] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2020] [Revised: 07/22/2020] [Accepted: 07/27/2020] [Indexed: 12/20/2022] Open
Abstract
The nucleus accumbens shell (NAcSh) regulates emotional and motivational responses, a function mediated, in part, by integrating and prioritizing extensive glutamatergic projections from limbic and paralimbic brain regions. Each of these inputs is thought to encode unique aspects of emotional and motivational arousal. The projections do not operate alone, but rather are often activated simultaneously during motivated behaviors, during which they can interact and coordinate in shaping behavioral output. To understand the anatomic and physiological bases underlying these interprojection interactions, the current study in mice of both sexes focused on how the basolateral amygdala projection (BLAp) to the NAcSh regulates, and is regulated by, projections from the medial prefrontal cortex (mPFCp) and paraventricular nucleus of the thalamus (PVTp). Using a dual-color SynaptoTag technique combined with a backfilling spine imaging strategy, we found that all three afferent projections primarily targeted the secondary dendrites of NAcSh medium spiny neurons, forming putative synapses. We detected a low percentage of BLAp contacts closely adjacent to mPFCp or PVTp presumed synapses, and, on some rare occasions, the BLAp formed heterosynaptic interactions with mPFCp or PVTp profiles or appeared to contact the same spines. Using dual-rhodopsin optogenetics, we detected signs of dendritic summation of BLAp with PVTp and mPFCp inputs. Furthermore, high-frequency activation of BLAp synchronous with the PVTp or mPFCp resulted in a transient enhancement of the PVTp, but not mPFCp, transmission. These results provide anatomic and functional indices that the BLAp interacts with the mPFCp and PVTp for informational processing within the NAcSh.SIGNIFICANCE STATEMENT The nucleus accumbens regulates emotional and motivational responses by integrating extensive glutamatergic projections, but the anatomic and physiological bases on which these projections integrate and interact remain underexplored. Here, we used dual-color synaptic markers combined with backfilling of nucleus accumbens medium spiny neurons to reveal some unique anatomic alignments of presumed synapses from the basolateral amygdala, medial prefrontal cortex, and paraventricular nucleus of thalamus. We also used dual-rhodopsin optogenetics in brain slices, which reveal a nonlinear interaction between some, but not all, projections. These results provide compelling anatomic and physiological mechanisms through which different glutamatergic projections to the nucleus accumbens, and possibly different aspects of emotional and motivational arousal, interact with each other for final behavioral output.
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Fu Y, Depue RA. A novel neurobehavioral framework of the effects of positive early postnatal experience on incentive and consummatory reward sensitivity. Neurosci Biobehav Rev 2019; 107:615-640. [DOI: 10.1016/j.neubiorev.2019.09.026] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2019] [Revised: 09/08/2019] [Accepted: 09/17/2019] [Indexed: 12/22/2022]
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Abstract
Acupuncture is an ancient therapy with a variety of different explanatory models. A cascade of physiological effects has been reported, both in the peripheral and the central nervous system, following the insertion of a needle or light tapping of the skin. Clinical trials testing the specific claims of acupuncture have generally tried to focus on testing the efficacy of applying specific techniques and/or specified points. However, different conditions may respond differently to different modes of stimulation. Recently, it was demonstrated that both superficial and deep needling (with de qi/Hibiki) resulted in amelioration of patellofemoral pain and unpleasantness. The pleasurable aspect of the acupuncture experience has largely been ignored as it has been considered secondary to its pain alleviating effects. This aspect of acupuncture treatment is likely to be related to activation of self-appraisal and the reward system. When a patient seeks a therapist there are expectations of a specific effect. These expectations are partly based on self-relevant phenomena and self-referentia introspection and constitute the preference. Also, when asked about the effect of the treatment, processes that orientate pre-attentive anticipatory or mnemonic information and processes that mediate self-reflection and recollection are integrated together with sensory detection to enable a decision about the patient's perception of the effect of acupuncture treatment. These ‘self-appraisal’ processes are dependent on two integrated networks: a ventral medial prefrontal cortex paralimbic limbic ‘affective’ pathway and a dorsal medial prefrontal cortex cortical hippocampal ‘cognitive’ pathway. The limbic structures are implicated in the reward system and play a key role in most diseases and illness responses including chronic pain and depression, regulating mood and neuromodulatory responses (eg sensory, autonomic, and endocrine). The pleasurable and neuromodulatory aspects of acupuncture as well as ‘placebo needling’ may partly be explained by the activation or deactivation of limbic structures including the hippocampus, amygdala, and their connections with the hypothalamus. In patients with patellofemoral pain, the effects of superficial and deep needling remained for six months. These long term pain-alleviating effects have been attributed to activation of pain inhibiting systems in cortical and subcortical pathways. When considering long term effects the cortical cerebellar system needs to be taken into account. The cortical cerebellar system is probably central to the development of neural models that learn and eventually stimulate routinely executed (eg motor skills) and long term (eg pain alleviation) cognitive processes. These higher order cognitive processes are initially mediated in prefrontal cortical loci but later shift control iteratively to internal cerebellar representations of these processes. Possibly part of the long term healing effects of acupuncture may be attributed to changes in the cerebellar system thereby sparing processing load in cortical and subcortical areas. As cortical and subcortical structures are activated and/or de-activated following stimulation of receptors in the skin, disregarding site, ‘placebo or sham needling’ does not exist and conclusions drawn on the basis that it is an inert control are invalid. ‘Self’ may be seen as a shifting illusion, ceaselessly constructed and deconstructed, and the effect of acupuncture may reflect its status (as well as that of the therapist).
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Affiliation(s)
- Thomas Lundeberg
- Rehabilitation Medicine, UniversityClinic, Danderyds Hospital, Stockholm, Sweden.
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Lenka A, Herath P, Christopher R, Pal PK. Psychosis in Parkinson's disease: From the soft signs to the hard science. J Neurol Sci 2017; 379:169-176. [PMID: 28716235 DOI: 10.1016/j.jns.2017.06.011] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2017] [Revised: 05/30/2017] [Accepted: 06/11/2017] [Indexed: 01/06/2023]
Abstract
Patients with Parkinson's disease (PD) may develop a wide spectrum of non-motor symptoms during the course of illness. Psychosis is one such commonly observed non-motor symptoms of PD. Although several studies based on neuroimaging, genetics, retinal imaging, and neuropsychological evaluations have explored the pathogenesis of psychosis in PD; exact neural correlates are yet to be understood. Identification of factors related to psychosis in PD is important, as psychosis has been reported to be associated with higher rates of mortality, caregiver distress, and nursing home placements. This review highlights the potential of the previous studies to gain further insights into the soft signs and hard science related to psychosis in PD. Studies based on neuropsychological evaluations have revealed significant dysfunction in attention, executive and visuospatial functions in patients with PD and psychosis. Neuroimaging studies reveal grey matter atrophy in regions of the brain corresponding to both dorsal and ventral visual pathways, hippocampus, and cholinergic structures. Meanwhile, functional imaging studies suggest existence of an aberrant top-to-bottom visual processing system, which dominates the normal bottom-to-top system in patients with PD and visual hallucinations. Although nucleotide polymorphisms of several genes have been studied in PD patients with psychosis, those on -45C>T polymorphisms of cholecystokinin gene (CCK) have shown the greatest promise because of its association with psychosis in PD. All these taken together, cohesively unfold the current status of research in patients with PD and psychosis. This paper also highlights the missing links and discusses the approach to future research in this field.
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Affiliation(s)
- Abhishek Lenka
- Department of Clinical Neurosciences, National Institute of Mental Health & Neurosciences (NIMHANS), Bangalore, India; Department of Neurology, National Institute of Mental Health & Neurosciences (NIMHANS), Bangalore, India
| | - Priyantha Herath
- Department of Neurology, University of South Carolina School of Medicine, Columbia, SC, USA
| | - Rita Christopher
- Department of Neurochemistry, National Institute of Mental Health & Neurosciences (NIMHANS), Bangalore, India
| | - Pramod Kumar Pal
- Department of Neurology, National Institute of Mental Health & Neurosciences (NIMHANS), Bangalore, India.
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Parikh V, Naughton SX, Yegla B, Guzman DM. Impact of partial dopamine depletion on cognitive flexibility in BDNF heterozygous mice. Psychopharmacology (Berl) 2016; 233:1361-75. [PMID: 26861892 PMCID: PMC4814303 DOI: 10.1007/s00213-016-4229-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/16/2015] [Accepted: 01/30/2016] [Indexed: 12/17/2022]
Abstract
RATIONALE Cognitive flexibility is a key component of executive function and is disrupted in major psychiatric disorders. Brain-derived neurotrophic factor (BDNF) exerts neuromodulatory effects on synaptic transmission and cognitive/affective behaviors. However, the causal mechanisms linking BDNF hypofunction with executive deficits are not well understood. OBJECTIVES Here, we assessed the consequences of BDNF hemizygosity on cognitive flexibility in mice performing an operant conditioning task. As dopaminergic-glutamatergic interaction in the striatum is important for cognitive processing, and BDNF heterozygous (BDNF(+/-)) mice display a higher dopamine tone in the dorsal striatum, we also assessed the effects of partial striatal dopamine depletion on task performance and glutamate release. RESULTS BDNF(+/-) mice acquired discrimination learning as well as new rule learning during set-shifting as efficiently as wild-type mice. However, partial removal of striatal dopaminergic inputs with 6-hydroxydopamine (6-OHDA) impaired these cognitive processes by impeding the maintenance of a new learning strategy in both genotypes. BDNF mutants exhibited performance impairments during reversal learning, and these deficits were associated with increased perseveration to the previously acquired strategy. Partial dopamine depletion of the striatum reversed these cognitive impairments. Additionally, reduction in depolarization-evoked glutamate release noted in the dorsal striatum of BDNF(+/-) mice was not observed in 6-OHDA-infused BDNF mutants indicating normalization of glutamatergic transmission in these animals. CONCLUSIONS Our data illustrate that BDNF signaling regulates cognitive control processes presumably by maintaining striatal dopamine-glutamate balance. Moreover, aberrations in BDNF signaling may act as a common neurobiological substrate that accounts for executive dysfunction observed in multiple psychiatric conditions.
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Affiliation(s)
- Vinay Parikh
- Department of Psychology and Neuroscience Program, Temple University, Philadelphia, PA, 19122, USA.
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Ross EK, Kim JP, Settell ML, Han SR, Blaha CD, Min HK, Lee KH. Fornix deep brain stimulation circuit effect is dependent on major excitatory transmission via the nucleus accumbens. Neuroimage 2016; 128:138-148. [PMID: 26780572 PMCID: PMC4764383 DOI: 10.1016/j.neuroimage.2015.12.056] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Revised: 12/04/2015] [Accepted: 12/31/2015] [Indexed: 01/21/2023] Open
Abstract
INTRODUCTION Deep brain stimulation (DBS) is a circuit-based treatment shown to relieve symptoms from multiple neurologic and neuropsychiatric disorders. In order to treat the memory deficit associated with Alzheimer's disease (AD), several clinical trials have tested the efficacy of DBS near the fornix. Early results from these studies indicated that patients who received fornix DBS experienced an improvement in memory and quality of life, yet the mechanisms behind this effect remain controversial. It is known that transmission between the medial limbic and corticolimbic circuits plays an integral role in declarative memory, and dysfunction at the circuit level results in various forms of dementia, including AD. Here, we aimed to determine the potential underlying mechanism of fornix DBS by examining the functional circuitry and brain structures engaged by fornix DBS. METHODS A multimodal approach was employed to examine global and local temporal changes that occur in an anesthetized swine model of fornix DBS. Changes in global functional activity were measured by functional MRI (fMRI), and local neurochemical changes were monitored by fast scan cyclic voltammetry (FSCV) during electrical stimulation of the fornix. Additionally, intracranial microinfusions into the nucleus accumbens (NAc) were performed to investigate the global activity changes that occur with dopamine and glutamate receptor-specific antagonism. RESULTS Hemodynamic responses in both medial limbic and corticolimbic circuits measured by fMRI were induced by fornix DBS. Additionally, fornix DBS resulted in increases in dopamine oxidation current (corresponding to dopamine efflux) monitored by FSCV in the NAc. Finally, fornix DBS-evoked hemodynamic responses in the amygdala and hippocampus decreased following dopamine and glutamate receptor antagonism in the NAc. CONCLUSIONS The present findings suggest that fornix DBS modulates dopamine release on presynaptic dopaminergic terminals in the NAc, involving excitatory glutamatergic input, and that the medial limbic and corticolimbic circuits interact in a functional loop.
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Affiliation(s)
- Erika K Ross
- Department of Neurologic Surgery, Mayo Clinic, Rochester, MN 55905, USA; Mayo Graduate School, Mayo Clinic, Rochester, MN 55905, USA
| | - Joo Pyung Kim
- Department of Neurologic Surgery, Mayo Clinic, Rochester, MN 55905, USA; Department of Neurosurgery, Bundang CHA Hospital, CHA University School of Medicine, Seongnam, Korea
| | - Megan L Settell
- Department of Neurologic Surgery, Mayo Clinic, Rochester, MN 55905, USA
| | - Seong Rok Han
- Department of Neurologic Surgery, Mayo Clinic, Rochester, MN 55905, USA; Department of Neurosurgery, Ilsan Paik Hospital, College of Medicine, Inje University, Goyang, Korea
| | - Charles D Blaha
- Department of Neurologic Surgery, Mayo Clinic, Rochester, MN 55905, USA
| | - Hoon-Ki Min
- Department of Neurologic Surgery, Mayo Clinic, Rochester, MN 55905, USA; Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN 55905, USA.
| | - Kendall H Lee
- Department of Neurologic Surgery, Mayo Clinic, Rochester, MN 55905, USA; Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN 55905, USA.
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Darbin O, Jin X, Von Wrangel C, Schwabe K, Nambu A, Naritoku DK, Krauss JK, Alam M. Neuronal Entropy-Rate Feature of Entopeduncular Nucleus in Rat Model of Parkinson's Disease. Int J Neural Syst 2015; 26:1550038. [PMID: 26711712 DOI: 10.1142/s0129065715500380] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The function of the nigro-striatal pathway on neuronal entropy in the basal ganglia (BG) output nucleus, i.e. the entopeduncular nucleus (EPN) was investigated in the unilaterally 6-hyroxydopamine (6-OHDA)-lesioned rat model of Parkinson's disease (PD). In both control subjects and subjects with 6-OHDA lesion of dopamine (DA) the nigro-striatal pathway, a histological hallmark for parkinsonism, neuronal entropy in EPN was maximal in neurons with firing rates ranging between 15 and 25 Hz. In 6-OHDA lesioned rats, neuronal entropy in the EPN was specifically higher in neurons with firing rates above 25 Hz. Our data establishes that the nigro-striatal pathway controls neuronal entropy in motor circuitry and that the parkinsonian condition is associated with abnormal relationship between firing rate and neuronal entropy in BG output nuclei. The neuronal firing rates and entropy relationship provide putative relevant electrophysiological information to investigate the sensory-motor processing in normal condition and conditions such as movement disorders.
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Affiliation(s)
- Olivier Darbin
- 1 Department of Neurology, University South Alabama, 307 University Blvd., Mobile, AL 36688, USA.,2 Division of System Neurophysiology, National Institute for Physiological Sciences, Okazaki, 444-8585, Japan.,3 Animal Resource Program, University Alabama at Birmingham, Birmingham, AL, USA
| | - Xingxing Jin
- 4 Department of Neurosurgery, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
| | - Christof Von Wrangel
- 4 Department of Neurosurgery, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
| | - Kerstin Schwabe
- 4 Department of Neurosurgery, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
| | - Atsushi Nambu
- 2 Division of System Neurophysiology, National Institute for Physiological Sciences, Okazaki, 444-8585, Japan.,5 Department of Physiological Sciences, SOKENDAI (The Graduate University for Advanced Studies), Okazaki, 444-8585, Japan
| | - Dean K Naritoku
- 1 Department of Neurology, University South Alabama, 307 University Blvd., Mobile, AL 36688, USA
| | - Joachim K Krauss
- 4 Department of Neurosurgery, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
| | - Mesbah Alam
- 4 Department of Neurosurgery, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
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Attention-Deficit/Hyperactivity Disorder-like Phenotype in a Mouse Model with Impaired Actin Dynamics. Biol Psychiatry 2015; 78:95-106. [PMID: 24768258 DOI: 10.1016/j.biopsych.2014.03.011] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/15/2013] [Revised: 03/05/2014] [Accepted: 03/05/2014] [Indexed: 11/23/2022]
Abstract
BACKGROUND Actin depolymerizing proteins of the actin depolymerizing factor (ADF)/cofilin family are essential for actin dynamics, which is critical for synaptic function. Two ADF/cofilin family members, ADF and n-cofilin, are highly abundant in the brain, where they are present in excitatory synapses. Previous studies demonstrated the relevance of n-cofilin for postsynaptic plasticity, associative learning, and anxiety. These studies also suggested overlapping functions for ADF and n-cofilin. METHODS We performed pharmacobehavioral, electrophysiologic, and electron microscopic studies on ADF and n-cofilin single mutants and double mutants (named ACC mice) to characterize the importance of ADF/cofilin activity for synapse physiology and mouse behavior. RESULTS The ACC mice, but not single mutants, exhibited hyperlocomotion, impulsivity, and impaired working memory. Hyperlocomotion and impulsive behavior were reversed by methylphenidate, a psychostimulant commonly used for the treatment of attention-deficit/hyperactivity disorder (ADHD). Also, ACC mice displayed a disturbed morphology of striatal excitatory synapses, accompanied by strongly increased glutamate release. Blockade of dopamine or glutamate transmission resulted in normal locomotion. CONCLUSIONS Our study reveals that ADHD can result from a disturbed balance between excitation and inhibition in striatal circuits, providing novel insights into the mechanisms underlying this neurobehavioral disorder. Our results link actin dynamics to ADHD, suggesting that mutations in actin regulatory proteins may contribute to the etiology of ADHD in humans.
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Affiliation(s)
- Brigham J. Hartley
- Departments of Psychiatry and Neuroscience, Mount Sinai School of
Medicine, 1425 Madison Avenue, New York, NY 10029
| | - Ngoc Tran
- Departments of Psychiatry and Neuroscience, Mount Sinai School of
Medicine, 1425 Madison Avenue, New York, NY 10029
| | - Ian Ladran
- Departments of Psychiatry and Neuroscience, Mount Sinai School of
Medicine, 1425 Madison Avenue, New York, NY 10029
| | - Kathryn Reggio
- Departments of Psychiatry and Neuroscience, Mount Sinai School of
Medicine, 1425 Madison Avenue, New York, NY 10029
| | - Kristen J. Brennand
- Departments of Psychiatry and Neuroscience, Mount Sinai School of
Medicine, 1425 Madison Avenue, New York, NY 10029
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Nakajima S, Takeuchi H, Plitman E, Fervaha G, Gerretsen P, Caravaggio F, Chung JK, Iwata Y, Remington G, Graff-Guerrero A. Neuroimaging findings in treatment-resistant schizophrenia: A systematic review: Lack of neuroimaging correlates of treatment-resistant schizophrenia. Schizophr Res 2015; 164:164-75. [PMID: 25684554 PMCID: PMC4409508 DOI: 10.1016/j.schres.2015.01.043] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Revised: 01/28/2015] [Accepted: 01/30/2015] [Indexed: 12/21/2022]
Abstract
BACKGROUND Recent developments in neuroimaging have advanced the understanding of biological mechanisms underlying schizophrenia. However, neuroimaging correlates of treatment-resistant schizophrenia (TRS) and superior effects of clozapine on TRS remain unclear. METHODS Systematic search was performed to identify neuroimaging characteristics unique to TRS and ultra-resistant schizophrenia (i.e. clozapine-resistant [URS]), and clozapine's efficacy in TRS using Embase, Medline, and PsychInfo. Search terms included (schizophreni*) and (resistan* OR refractory OR clozapine) and (ASL OR CT OR DTI OR FMRI OR MRI OR MRS OR NIRS OR PET OR SPECT). RESULTS 25 neuroimaging studies have investigated TRS and effects of clozapine. Only 5 studies have compared TRS and non-TRS, collectively providing no replicated neuroimaging finding specific to TRS. Studies comparing TRS and healthy controls suggest that hypometabolism in the prefrontal cortex, hypermetabolism in the basal ganglia, and structural anomalies in the corpus callosum contribute to TRS. Clozapine may increase prefrontal hypoactivation in TRS although this was not related to clinical improvement; in contrast, evidence has suggested a link between clozapine efficacy and decreased metabolism in the basal ganglia and thalamus. CONCLUSION Existing literature does not elucidate neuroimaging correlates specific to TRS or URS, which, if present, might also shed light on clozapine's efficacy in TRS. This said, leads from other lines of investigation, including the glutamatergic system can prove useful in guiding future neuroimaging studies focused on, in particular, the frontocortical-basal ganglia-thalamic circuits. Critical to the success of this work will be precise subtyping of study subjects based on treatment response/nonresponse and the use of multimodal neuroimaging.
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Affiliation(s)
- Shinichiro Nakajima
- Multimodal Imaging Group - Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, Canada; Geriatric Mental Health Division, Centre for Addiction and Mental Health, Toronto, Canada; Department of Psychiatry, University of Toronto, Toronto, Canada; Department of Neuropsychiatry, School of Medicine, Keio University, Tokyo, Japan.
| | - Hiroyoshi Takeuchi
- Department of Psychiatry, University of Toronto, Toronto, Canada; Department of Neuropsychiatry, School of Medicine, Keio University, Tokyo, Japan; Schizophrenia Division, Complex Mental Illness Program, Centre for Addiction and Mental Health, Toronto, Canada.
| | - Eric Plitman
- Multimodal Imaging Group - Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, Canada; Institute of Medical Science, University of Toronto, Toronto, Canada.
| | - Gagan Fervaha
- Schizophrenia Division, Complex Mental Illness Program, Centre for Addiction and Mental Health, Toronto, Canada; Institute of Medical Science, University of Toronto, Toronto, Canada.
| | - Philip Gerretsen
- Multimodal Imaging Group - Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, Canada; Geriatric Mental Health Division, Centre for Addiction and Mental Health, Toronto, Canada; Department of Psychiatry, University of Toronto, Toronto, Canada; Institute of Medical Science, University of Toronto, Toronto, Canada.
| | - Fernando Caravaggio
- Multimodal Imaging Group - Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, Canada; Institute of Medical Science, University of Toronto, Toronto, Canada.
| | - Jun Ku Chung
- Multimodal Imaging Group - Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, Canada; Institute of Medical Science, University of Toronto, Toronto, Canada.
| | - Yusuke Iwata
- Multimodal Imaging Group - Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, Canada; Department of Psychiatry, University of Toronto, Toronto, Canada; Department of Neuropsychiatry, School of Medicine, Keio University, Tokyo, Japan.
| | - Gary Remington
- Department of Psychiatry, University of Toronto, Toronto, Canada; Schizophrenia Division, Complex Mental Illness Program, Centre for Addiction and Mental Health, Toronto, Canada; Campbell Research Institute, Centre for Addiction and Mental Health, Toronto, Canada.
| | - Ariel Graff-Guerrero
- Multimodal Imaging Group - Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, Canada; Geriatric Mental Health Division, Centre for Addiction and Mental Health, Toronto, Canada; Department of Psychiatry, University of Toronto, Toronto, Canada; Campbell Research Institute, Centre for Addiction and Mental Health, Toronto, Canada.
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Li SSY, McNally GP. Selecting danger signals: dissociable roles of nucleus accumbens shell and core glutamate in predictive fear learning. Eur J Neurosci 2015; 41:1515-23. [DOI: 10.1111/ejn.12892] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2014] [Revised: 03/03/2015] [Accepted: 03/05/2015] [Indexed: 12/23/2022]
Affiliation(s)
- Susan S. Y. Li
- School of Psychology; UNSW Australia; Sydney NSW Australia
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Gray CL, Norvelle A, Larkin T, Huhman KL. Dopamine in the nucleus accumbens modulates the memory of social defeat in Syrian hamsters (Mesocricetus auratus). Behav Brain Res 2015; 286:22-8. [PMID: 25721736 DOI: 10.1016/j.bbr.2015.02.030] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2014] [Revised: 02/10/2015] [Accepted: 02/16/2015] [Indexed: 11/17/2022]
Abstract
Conditioned defeat (CD) is a behavioral response that occurs in Syrian hamsters after they experience social defeat. Subsequently, defeated hamsters no longer produce territorial aggression but instead exhibit heightened levels of avoidance and submission, even when confronted with a smaller, non-aggressive intruder. Dopamine in the nucleus accumbens is hypothesized to act as a signal of salience for both rewarding and aversive stimuli to promote memory formation and appropriate behavioral responses to significant events. The purpose of the present study was to test the hypothesis that dopamine in the nucleus accumbens modulates the acquisition and expression of behavioral responses to social defeat. In Experiment 1, bilateral infusion of the non-specific D1/D2 receptor antagonist cis(z)flupenthixol (3.75 μg/150 nl saline) into the nucleus accumbens 5 min prior to defeat training significantly reduced submissive and defensive behavior expressed 24h later in response to a non-aggressive intruder. In Experiment 2, infusion of 3.75 μg cis-(Z)-flupenthixol 5 min before conditioned defeat testing with a non-aggressive intruder significantly increased aggressive behavior in drug-infused subjects. In Experiment 3, we found that the effect of cis-(Z)-flupenthixol on aggression was specific to defeated animals as infusion of drug into the nucleus accumbens of non-defeated animals did not significantly alter their behavior in response to a non-aggressive intruder. These data demonstrate that dopamine in the nucleus accumbens modulates both acquisition and expression of social stress-induced behavioral changes and suggest that the nucleus accumbens plays an important role in the suppression of aggression that is observed after social defeat.
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Affiliation(s)
- C L Gray
- Neuroscience Institute, Morehouse School of Medicine, Atlanta, GA 30310, USA
| | - A Norvelle
- Neuroscience Institute, Georgia State University, Atlanta, GA 30302, USA
| | - T Larkin
- Neuroscience Institute, Georgia State University, Atlanta, GA 30302, USA
| | - K L Huhman
- Neuroscience Institute, Georgia State University, Atlanta, GA 30302, USA.
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15
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Xu S, Gullapalli RP, Frost DO. Olanzapine antipsychotic treatment of adolescent rats causes long term changes in glutamate and GABA levels in the nucleus accumbens. Schizophr Res 2015; 161:452-7. [PMID: 25487700 PMCID: PMC4308953 DOI: 10.1016/j.schres.2014.10.034] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2014] [Revised: 10/20/2014] [Accepted: 10/23/2014] [Indexed: 10/24/2022]
Abstract
Atypical antipsychotic drugs (AAPDs) are widely used in children and adolescents to treat a variety of psychiatric disorders. However, little is known about the long-term effects of AAPD treatment before the brain is fully developed. Indeed, we and others have previously reported that treatment of adolescent rats with olanzapine (OLA; a widely prescribed AAPD) on postnatal days 28-49, under dosing conditions that approximate those employed therapeutically in humans, causes long-term behavioral and neurobiological perturbations. We have begun to study the mechanisms of these effects. Dopamine (DA) and serotonin (5HT) regulate many neurodevelopmental processes. Currently approved AAPDs exert their therapeutic effects principally through their DAergic activities, although in schizophrenia (SZ) and some other diseases for which AAPDs are prescribed, DAergic dysfunction is accompanied by abnormalities of glutamatergic (GLUergic) and γ-aminobutyric acidergic (GABAergic) transmission. Here, we use proton magnetic resonance spectroscopy ((1)H MRS) to investigate the effects of adolescent OLA administration on GABA and GLU levels. We found that the treatment caused long-term reductions in the levels of both GLU and GABA in the nucleus accumbens (NAc) of adult rats treated with OLA during adolescence. The NAc is a key node in the brain's "reward" system, whose function is also disrupted in schizophrenia. Further research into potential, OLA-induced changes in the levels of GLU and GABA in the NAc and other brain areas, and the dynamics and mechanisms of those changes, are an essential step for devising new adjunct therapies for existing AAPDs and for designing new drugs that increase therapeutic effects and reduce long-term abnormalities when administered to pediatric patients.
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Affiliation(s)
- Su Xu
- Dept. of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Rao P Gullapalli
- Dept. of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Douglas O Frost
- Dept. of Pharmacology, University of Maryland School of Medicine, Baltimore, MD 21201, USA; Dept. of Psychiatry, University of Maryland School of Medicine, Baltimore, MD 21201, USA.
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16
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Glutamate, GABA, and glutamine are synchronously upregulated in the mouse lateral septum during the postpartum period. Brain Res 2014; 1591:53-62. [PMID: 25451092 DOI: 10.1016/j.brainres.2014.10.023] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2014] [Revised: 09/26/2014] [Accepted: 10/13/2014] [Indexed: 01/12/2023]
Abstract
Dramatic structural and functional remodeling occurs in the postpartum brain for the establishment of maternal care, which is essential for the growth and development of young offspring. Glutamate and GABA signaling are critically important in modulating multiple behavioral performances. Large scale signaling changes occur in the postpartum brain, but it is still not clear to what extent the neurotransmitters glutamate and GABA change and whether the ratio of glutamate/GABA remains balanced. In this study, we examined the glutamate/GABA-glutamine cycle in the lateral septum (LS) of postpartum female mice. In postpartum females (relative to virgins), tissue levels of glutamate and GABA were elevated in LS and increased mRNA was found for the respective enzymes producing glutamate and GABA, glutaminase (Gls) and glutamate decarboxylase 1 and 2 (Gad1 and Gad2). The common precursor, glutamine, was elevated as was the enzyme that produces it, glutamate-ammonia ligase (Glul). Additionally, glutamate, GABA, and glutamine were positively correlated and the glutamate/GABA ratio was almost identical in the postpartum and virgin females. Collectively, these findings indicate that glutamate and GABA signaling are increased and that the ratio of glutamate/GABA is well balanced in the maternal LS. The postpartum brain may provide a useful model system for understanding how glutamate and GABA are linked despite large signaling changes. Given that some mental health disorders, including depression and schizophrenia display dysregulated glutamate/GABA ratio, and there is increased vulnerability to mental disorders in mothers, it is possible that these postpartum disorders emerge when glutamate and GABA changes are not properly coordinated.
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17
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Yang JH, Choe ES. Protein kinase G regulates β-synuclein in response to repeated exposure to cocaine in the rat dorsal striatum in a Ca²⁺-dependent manner. Neurosci Lett 2014; 582:6-11. [PMID: 25181031 DOI: 10.1016/j.neulet.2014.08.042] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2014] [Revised: 08/22/2014] [Accepted: 08/25/2014] [Indexed: 11/28/2022]
Abstract
Protein kinase G (PKG) activation plays a crucial role in neuronal plasticity after repeated exposure to cocaine in the dorsal striatum. The present study investigated the characteristics of β-synuclein expression by PKG activation after repeated cocaine administration in the rat dorsal striatum. The results demonstrated that repeated, but not acute, exposure to cocaine (20mg/kg) once a day for 7 consecutive days significantly upregulated expression of β-synuclein. Furthermore, this upregulation was decreased by the depletion of Ca(2+), but not blockade of Na(+) influx. Blockade of N-methyl-d-aspartate (NMDA) receptors and ryanodine-sensitive Ca(2+) channels also decreased the elevation of β-synuclein expression by repeated cocaine administration. Inhibition of neuronal nitric oxide synthase, which can activate PKG, did not alter the expression of β-synuclein elevated by repeated cocaine administration. These findings suggest that the expression of β-synuclein can be regulated by Ca(2+)-dependent PKG activation via stimulation of NMDA receptors and voltage-operated Ca(2+) channels in the endoplasmic reticulum in the dorsal striatum.
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Affiliation(s)
- Ju Hwan Yang
- Department of Biological Sciences, Pusan National University, 63-2 Pusandaehak-ro, Kumjeong-gu, Pusan 609-735, Republic of Korea
| | - Eun Sang Choe
- Department of Biological Sciences, Pusan National University, 63-2 Pusandaehak-ro, Kumjeong-gu, Pusan 609-735, Republic of Korea.
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18
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Parikh V, Naughton SX, Shi X, Kelley LK, Yegla B, Tallarida CS, Rawls SM, Unterwald EM. Cocaine-induced neuroadaptations in the dorsal striatum: Glutamate dynamics and behavioral sensitization. Neurochem Int 2014; 75:54-65. [DOI: 10.1016/j.neuint.2014.05.016] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2014] [Revised: 05/13/2014] [Accepted: 05/29/2014] [Indexed: 10/25/2022]
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19
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Uthayathas S, Masilamoni GJ, Shaffer CL, Schmidt CJ, Menniti FS, Papa SM. Phosphodiesterase 10A inhibitor MP-10 effects in primates: comparison with risperidone and mechanistic implications. Neuropharmacology 2014; 77:257-67. [PMID: 24490227 PMCID: PMC3934827 DOI: 10.1016/j.neuropharm.2013.10.015] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Phosphodiesterase 10A (PDE10A) is highly expressed in striatal medium spiny neurons of both the direct and indirect output pathways. Similar to dopamine D₂ receptor antagonists acting on indirect pathway neurons, PDE10A inhibitors have shown behavioral effects in rodent models that predict antipsychotic efficacy. These findings have supported the clinical investigation of PDE10A inhibitors as a new treatment for schizophrenia. However, PDE10A inhibitors and D₂ antagonists differ in effects on direct pathway and other neurons of the basal ganglia, indicating that these two drug classes may have divergent antipsychotic efficacy and side effect profile. In the present study, we compare the behavioral effects of the selective PDE10A inhibitor MP-10 to those of the clinical standard D₂ antagonist risperidone in rhesus monkeys using a standardized motor disability scale for parkinsonian primates and a newly designed "Drug Effects on Nervous System" scale to assess non-motor effects. Behavioral effects of MP-10 correlated with its plasma levels and its regulation of metabolic activity in striatal and cortical regions as measured by FDG-PET imaging. While MP-10 and risperidone broadly impacted similar behavioral domains in the primate, their effects had a different underlying basis. MP-10-treated animals retained the ability to respond but did not engage tasks, whereas risperidone-treated animals retained the motivation to respond but were unable to perform the intended actions. These findings are discussed in light of what is currently known about the modulation of striatal circuitry by these two classes of compounds, and provide insight into interpreting emerging clinical data with PDE10A inhibitors for the treatment of psychotic symptoms.
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Affiliation(s)
- Subramaniam Uthayathas
- Division of Neuropharmacology and Neurologic Diseases, Yerkes National Primate Research Center, Emory University, Atlanta, GA
| | - Gunasingh J. Masilamoni
- Division of Neuropharmacology and Neurologic Diseases, Yerkes National Primate Research Center, Emory University, Atlanta, GA
| | - Christopher L. Shaffer
- Department of Pharmacokinetics, Pharmacodynamics and Metabolism, Worldwide Research and Development, Pfizer Inc., Cambridge, MA
| | - Christopher J. Schmidt
- Neuroscience Research Unit, Worldwide Research and Development, Pfizer Inc., Cambridge, MA
| | | | - Stella M. Papa
- Division of Neuropharmacology and Neurologic Diseases, Yerkes National Primate Research Center, Emory University, Atlanta, GA
- Department of Neurology, Emory University, Atlanta, GA
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20
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D'Amore DE, Tracy BA, Parikh V. Exogenous BDNF facilitates strategy set-shifting by modulating glutamate dynamics in the dorsal striatum. Neuropharmacology 2013; 75:312-23. [DOI: 10.1016/j.neuropharm.2013.07.033] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2013] [Revised: 07/29/2013] [Accepted: 07/30/2013] [Indexed: 01/19/2023]
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21
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Elman I, Borsook D, Volkow ND. Pain and suicidality: insights from reward and addiction neuroscience. Prog Neurobiol 2013; 109:1-27. [PMID: 23827972 PMCID: PMC4827340 DOI: 10.1016/j.pneurobio.2013.06.003] [Citation(s) in RCA: 150] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2013] [Revised: 06/03/2013] [Accepted: 06/18/2013] [Indexed: 01/09/2023]
Abstract
Suicidality is exceedingly prevalent in pain patients. Although the pathophysiology of this link remains unclear, it may be potentially related to the partial congruence of physical and emotional pain systems. The latter system's role in suicide is also conspicuous during setbacks and losses sustained in the context of social attachments. Here we propose a model based on the neural pathways mediating reward and anti-reward (i.e., allostatic adjustment to recurrent activation of the reward circuitry); both are relevant etiologic factors in pain, suicide and social attachments. A comprehensive literature search on neurobiology of pain and suicidality was performed. The collected articles were critically reviewed and relevant data were extracted and summarized within four key areas: (1) physical and emotional pain, (2) emotional pain and social attachments, (3) pain- and suicide-related alterations of the reward and anti-reward circuits as compared to addiction, which is the premier probe for dysfunction of these circuits and (4) mechanistically informed treatments of co-occurring pain and suicidality. Pain-, stress- and analgesic drugs-induced opponent and proponent states of the mesolimbic dopaminergic pathways may render reward and anti-reward systems vulnerable to sensitization, cross-sensitization and aberrant learning of contents and contexts associated with suicidal acts and behaviors. These findings suggest that pain patients exhibit alterations in the brain circuits mediating reward (depressed function) and anti-reward (sensitized function) that may affect their proclivity for suicide and support pain and suicidality classification among other "reward deficiency syndromes" and a new proposal for "enhanced anti-reward syndromes". We suggest that interventions aimed at restoring the balance between the reward and anti-reward networks in patients with chronic pain may help decreasing their suicide risk.
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Affiliation(s)
- Igor Elman
- Providence VA Medical Center and Cambridge Health Alliance, Harvard Medical School, 26 Central Street, Somerville, MA 02143, USA.
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22
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An entropy-based model for basal ganglia dysfunctions in movement disorders. BIOMED RESEARCH INTERNATIONAL 2013; 2013:742671. [PMID: 23762856 PMCID: PMC3671275 DOI: 10.1155/2013/742671] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/27/2013] [Accepted: 05/06/2013] [Indexed: 11/18/2022]
Abstract
During this last decade, nonlinear analyses have been used to characterize the irregularity that exists in the neuronal data stream of the basal ganglia. In comparison to linear parameters for disparity (i.e., rate, standard deviation, and oscillatory activities), nonlinear analyses focus on complex patterns that are composed of groups of interspike intervals with matching lengths but not necessarily contiguous in the data stream. In light of recent animal and clinical studies, we present a review and commentary on the basal ganglia neuronal entropy in the context of movement disorders.
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23
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di Michele F, Luchetti S, Bernardi G, Romeo E, Longone P. Neurosteroid and neurotransmitter alterations in Parkinson's disease. Front Neuroendocrinol 2013; 34:132-42. [PMID: 23563222 DOI: 10.1016/j.yfrne.2013.03.001] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2012] [Revised: 02/17/2013] [Accepted: 03/25/2013] [Indexed: 01/13/2023]
Abstract
Parkinson's disease (PD) is associated with a massive loss of dopaminergic cells in the substantia nigra leading to dopamine hypofunction and alteration of the basal ganglia circuitry. These neurons, are under the control, among others, of the excitatory glutamatergic and inhibitory γ-aminobutyric acid (GABA) systems. An imbalance between these systems may contribute to excitotoxicity and dopaminergic cell death. Neurosteroids, a group of steroid hormones synthesized in the brain, modulate the function of several neurotransmitter systems. The substantia nigra of the human brain expresses high concentrations of allopregnanolone (3α, 5αtetrahydroprogesterone), a neurosteroid that positively modulates the action of GABA at GABAA receptors and of 5α-dihydroprogesterone, a neurosteroid acting at the genomic level. This article reviews the roles of NS acting as neuroprotectants and as GABAA receptor agonists in the physiology and pathophysiology of the basal ganglia, their impact on dopaminergic cell activity and survival, and potential therapeutic application in PD.
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24
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Dopamine-glutamate interplay in the ventral striatum modulates spatial learning in a receptor subtype-dependent manner. Neuropsychopharmacology 2012; 37:1122-33. [PMID: 22218092 PMCID: PMC3306874 DOI: 10.1038/npp.2011.296] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The ventral striatum (VS) is characterized by a distinctive neural architecture in which multiple corticolimbic glutamatergic (GLUergic) and mesolimbic dopaminergic (DAergic) afferents converge on the same output cell type (the medium-sized spiny neuron, MSN). However, despite the gateway function attributed to VS and its involvement in action selection and spatial navigation, as well as the evidence of physical and functional receptor-receptor interaction between different members of ionotropic GLUergic and DAergic receptors, there is no available knowledge that such reciprocal interaction may be critical in shaping the ability to learn novel spatial and non-spatial arrangement of stimuli. In this study, it was evaluated whether intra-VS bilateral infusion of either N-methyl-D-aspartate (NMDA) or α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor-selective antagonists may suppress the ability to detect spatial or non-spatial novelty in a non-associative behavioral task. In a second set of experiments, we further examined the hypothesis that VS-mediated spatial information processing may be subserved by some preferential receptor-receptor interactions among specific GLUergic and DAergic receptor subtypes. This was assessed by concomitant intra-VS infusion of the combination between subthreshold doses of either NMDA or AMPA receptor antagonists with individual D1 or D2 receptor blockade. The results of this study highlighted the fact that NMDA or AMPA receptors are differentially involved in processing of spatial and non-spatial novelty, and showed for the first time that preferential NMDA/D1 and AMPA/D2 receptor-receptor functional communication, but not NMDA/D2 and AMPA/D1, is required for enabling learning of novel spatial information in the VS.
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25
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Luckett C, Norvelle A, Huhman K. The role of the nucleus accumbens in the acquisition and expression of conditioned defeat. Behav Brain Res 2011; 227:208-14. [PMID: 22024431 DOI: 10.1016/j.bbr.2011.10.012] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2011] [Revised: 09/16/2011] [Accepted: 10/07/2011] [Indexed: 01/16/2023]
Abstract
When Syrian hamsters (Mesocricetus auratus) are defeated by a larger, more aggressive hamster, they subsequently exhibit submissive and defensive behavior, instead of their usual aggressive and social behavior, even toward a smaller, non-aggressive opponent. This change in behavior is termed conditioned defeat, and we have found that the amygdala, bed nucleus of the stria terminalis, and ventral hippocampus, among others, are crucial brain areas for either the acquisition and/or expression of this behavioral response to social stress. In the present study, we tested the hypothesis that the nucleus accumbens is also a necessary component of the circuit mediating the acquisition and expression of conditioned defeat. We found that infusion of the GABA(A) agonist muscimol into the nucleus accumbens prior to defeat training failed to affect acquisition of conditioned defeat, but infusion prior to testing significantly decreased submissive behavior and significantly increased aggressive behavior directed toward the non-aggressive intruder. These data indicate that, unlike the basolateral complex of the amygdala, the nucleus accumbens is not a critical site for the plasticity underlying conditioned defeat acquisition, but it does appear to be an important component of the circuit mediating the expression of the behavioral changes that are produced in response to a previous social defeat. Of note, this is the first component of the putative "conditioned defeat neural circuit" wherein we have found that pharmacological manipulations are effective in restoring the territorial aggressive response in previously defeated hamsters.
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Affiliation(s)
- Cloe Luckett
- Neuroscience Institute, Georgia State University, 161 Jesse Hill Jr. Drive, Atlanta, GA 30303, USA.
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26
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Fuente-Sandoval CDL, León-Ortiz P, Favila R, Stephano S, Mamo D, Ramírez-Bermúdez J, Graff-Guerrero A. Higher levels of glutamate in the associative-striatum of subjects with prodromal symptoms of schizophrenia and patients with first-episode psychosis. Neuropsychopharmacology 2011; 36:1781-91. [PMID: 21508933 PMCID: PMC3154101 DOI: 10.1038/npp.2011.65] [Citation(s) in RCA: 190] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The glutamatergic and dopaminergic systems are thought to be involved in the pathophysiology of schizophrenia. Their interaction has been widely documented and may have a role in the neurobiological basis of the disease. The aim of this study was to compare, using proton magnetic resonance spectroscopy ((1)H-MRS), glutamate levels in the precommissural dorsal-caudate (a dopamine-rich region) and the cerebellar cortex (negligible for dopamine) in the following: (1) 18 antipsychotic-naïve subjects with prodromal symptoms and considered to be at ultra high-risk for schizophrenia (UHR), (2) 18 antipsychotic-naïve first- episode psychosis patients (FEP), and (3) 40 age- and sex- matched healthy controls. All subjects underwent a (1)H-MRS study using a 3Tesla scanner. Glutamate levels were quantified and corrected for the proportion of cerebrospinal fluid and percentage of gray matter in the voxel. The UHR and FEP groups showed higher levels of glutamate than controls, without differences between UHR and FEP. In the cerebellum, no differences were seen between the three groups. The higher glutamate level in the precommissural dorsal-caudate and not in the cerebellum of UHR and FEP suggests that a high glutamate level (a) precedes the onset of schizophrenia, and (b) is present in a dopamine-rich region previously implicated in the pathophysiology of schizophrenia.
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Affiliation(s)
- Camilo de la Fuente-Sandoval
- Experimental Psychiatry Laboratory, Instituto Nacional de Neurología y Neurocirugía, Mexico City, Mexico,Neuropsychiatry Department, Instituto Nacional de Neurología y Neurocirugía, Mexico City, Mexico
| | - Pablo León-Ortiz
- Neuropsychiatry Department, Instituto Nacional de Neurología y Neurocirugía, Mexico City, Mexico
| | - Rafael Favila
- MR Advanced Applications, GE Healthcare, Mexico City, Mexico
| | - Sylvana Stephano
- Neuropsychiatry Department, Instituto Nacional de Neurología y Neurocirugía, Mexico City, Mexico
| | - David Mamo
- Multimodal Neuroimaging Schizophrenia Group, PET Centre, Centre for Addiction and Mental Health & Department of Psychiatry, University of Toronto, Toronto, ON, Canada
| | - Jesús Ramírez-Bermúdez
- Neuropsychiatry Department, Instituto Nacional de Neurología y Neurocirugía, Mexico City, Mexico
| | - Ariel Graff-Guerrero
- Multimodal Neuroimaging Schizophrenia Group, PET Centre, Centre for Addiction and Mental Health & Department of Psychiatry, University of Toronto, Toronto, ON, Canada,Multimodal Neuroimaging Schizophrenia Group, PET Centre, Centre for Addiction and Mental Health, 250 College Street, Toronto, Ontario, Canada M5T 1R8. Tel: +1 416 535 8501 Ext 7376, Fax: +1 416 979 3855, E-mail:
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27
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Ko JH, Strafella AP. Dopaminergic neurotransmission in the human brain: new lessons from perturbation and imaging. Neuroscientist 2011; 18:149-68. [PMID: 21536838 DOI: 10.1177/1073858411401413] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Dopamine plays an important role in several brain functions and is involved in the pathogenesis of several psychiatric and neurological disorders. Neuroimaging techniques such as positron emission tomography allow us to quantify dopaminergic activity in the living human brain. Combining these with brain stimulation techniques offers us the unique opportunity to tackle questions regarding region-specific neurochemical activity. Such studies may aid clinicians and scientists to disentangle neural circuitries within the human brain and thereby help them to understand the underlying mechanisms of a given function in relation to brain diseases. Furthermore, it may also aid the development of alternative treatment approaches for various neurological and psychiatric conditions.
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Affiliation(s)
- Ji Hyun Ko
- PET Imaging Centre, Centre for Addiction and Mental Health, University of Toronto, Ontario, Canada
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28
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Gormley S, Rompré PP. Blockade of mGLUR5 receptors differentially alters amphetamine-induced enhancement of locomotor activity and of brain stimulation reward. J Psychopharmacol 2011; 25:393-401. [PMID: 20498134 DOI: 10.1177/0269881110367460] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
This study was aimed at determining the role of mGLUR5 glutamate receptors on amphetamine-induced enhancement of locomotion and of brain stimulation reward (BSR). The effect of different doses of the mGLUR5 antagonist, MPEP (0, 1, 3 and 9 mg/kg, i.p.), was assessed on reward induced by electrical stimulation of the lateral hypothalamus, and on the enhancement of reward by amphetamine (1 mg/kg, i.p.) in adult male Long Evans rats. The effect of a single dose of MPEP (0 and 9 mg/kg) on amphetamine-induced increase in locomotor activity was also assessed. Systemic injection of MPEP alone did not alter reward threshold and maximum rate of responding. Amphetamine produced a 25-30% decrease in reward threshold, an effect not altered by the highest dose of MPEP. At this dose, MPEP produced a weak inhibition of spontaneous locomotion and a significant attenuation of the enhanced locomotor activity induced by amphetamine. These findings show that mGLUR5 glutamate receptors are unlikely to constitute important elements of the reward-relevant pathway, and do not intervene in the enhancement effect of amphetamine. They also show, however, that these glutamate receptors play a key role in amphetamine-induced increased locomotor activity, providing additional evidence for a dissociation between the substrates that mediate these two behaviours.
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29
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Ondracek JM, Willuhn I, Steiner H, West AR. Interactions between Procedural Learning and Cocaine Exposure Alter Spontaneous and Cortically Evoked Spike Activity in the Dorsal Striatum. Front Neurosci 2011; 4:206. [PMID: 21228909 PMCID: PMC3017361 DOI: 10.3389/fnins.2010.00206] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2010] [Accepted: 12/15/2010] [Indexed: 11/13/2022] Open
Abstract
We have previously shown that cocaine enhances gene regulation in the sensorimotor striatum associated with procedural learning in a running-wheel paradigm. Here we assessed whether cocaine produces enduring modifications of learning-related changes in striatal neuron activity, using single-unit recordings in anesthetized rats 1 day after the wheel training. Spontaneous and cortically evoked spike activity was compared between groups treated with cocaine or vehicle immediately prior to the running-wheel training or placement in a locked wheel (control conditions). We found that wheel training in vehicle-treated rats increased the average firing rate of spontaneously active neurons without changing the relative proportion of active to quiescent cells. In contrast, in rats trained under the influence of cocaine, the proportion of spontaneously firing to quiescent cells was significantly greater than in vehicle-treated, trained rats. However, this effect was associated with a lower average firing rate in these spontaneously active cells, suggesting that training under the influence of cocaine recruited additional low-firing cells. Measures of cortically evoked activity revealed a second interaction between cocaine treatment and wheel training, namely, a cocaine-induced decrease in spike onset latency in control rats (locked wheel). This facilitatory effect of cocaine was abolished when rats trained in the running wheel during cocaine action. These findings highlight important interactions between cocaine and procedural learning, which act to modify population firing activity and the responsiveness of striatal neurons to excitatory inputs. Moreover, these effects were found 24 h after the training and last drug exposure indicating that cocaine exposure during the learning phase triggers long-lasting changes in synaptic plasticity in the dorsal striatum. Such changes may contribute to the transition from recreational to habitual or compulsive drug taking behavior.
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Affiliation(s)
- Janie M Ondracek
- Department of Cellular and Molecular Pharmacology, The Chicago Medical School/Rosalind Franklin University of Medicine and Science North Chicago, IL, USA
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T-type calcium channel antagonism produces antipsychotic-like effects and reduces stimulant-induced glutamate release in the nucleus accumbens of rats. Neuropharmacology 2010; 62:1413-21. [PMID: 21110986 DOI: 10.1016/j.neuropharm.2010.11.015] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2010] [Revised: 11/08/2010] [Accepted: 11/17/2010] [Indexed: 11/23/2022]
Abstract
T-type calcium channels are important in burst firing and expressed in brain regions implicated in schizophrenia. Therefore, we examined the effects of novel selective T-type calcium channel antagonists in preclinical assays predictive of antipsychotic-like activity. TTA-A2 blocked the psychostimulant effects of amphetamine and MK-801 and decreased conditioned avoidance responding. These effects appeared mechanism based, rather than compound specific, as two structurally dissimilar T-type antagonists also reduced amphetamine-induced psychomotor activity. Importantly, the ability to reduce amphetamine's effects was maintained following 20 days pre-treatment with TTA-A2. To explore the neural substrates mediating the observed behavioral effects, we examined the influence of TTA-A2 on amphetamine-induced c-fos expression as well as basal and stimulant-evoked dopamine and glutamate release in the nucleus accumbens. TTA-A2 decreased amphetamine-induced c-fos expression as well as MK-801-induced, but not basal, glutamate levels in the nucleus accumbens. Basal, amphetamine- and MK-801-induced dopamine efflux was altered. These findings suggest that T-type calcium channel antagonism could represent a novel mechanism for treating schizophrenia.
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Austin P, Beyer K, Bembrick A, Keay K. Peripheral nerve injury differentially regulates dopaminergic pathways in the nucleus accumbens of rats with either ‘pain alone’ or ‘pain and disability’. Neuroscience 2010; 171:329-43. [DOI: 10.1016/j.neuroscience.2010.08.040] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2010] [Revised: 08/18/2010] [Accepted: 08/19/2010] [Indexed: 10/19/2022]
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Barch DM, Dowd EC. Goal representations and motivational drive in schizophrenia: the role of prefrontal-striatal interactions. Schizophr Bull 2010; 36:919-34. [PMID: 20566491 PMCID: PMC2930335 DOI: 10.1093/schbul/sbq068] [Citation(s) in RCA: 347] [Impact Index Per Article: 24.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The past several years have seen a resurgence of interest in understanding the psychological and neural bases of what are often referred to as "negative symptoms" in schizophrenia. These aspects of schizophrenia include constructs such as asociality, avolition (a reduction in the motivation to initiate or persist in goal-directed behavior), and anhedonia (a reduction in the ability to experience pleasure). We believe that these dimensions of impairment in individuals with schizophrenia reflect difficulties using internal representations of emotional experiences, previous rewards, and motivational goals to drive current and future behavior in a way that would allow them to obtain desired outcomes, a deficit that has major clinical significance in terms of functional capacity. In this article, we review the major components of the systems that link experienced and anticipated rewards with motivated behavior that could potentially be impaired in schizophrenia. We conclude that the existing evidence suggests relatively intact hedonics in schizophrenia, but impairments in some aspects of reinforcement learning, reward prediction, and prediction error processing, consistent with an impairment in "wanting." As of yet, there is only indirect evidence of impairment in anterior cingulate and orbital frontal function that may support value and effort computations. However, there are intriguing hints that individuals with schizophrenia may not be able to use reward information to modulate cognitive control and dorsolateral prefrontal cortex function, suggesting a potentially important role for cortical-striatal interactions in mediating impairment in motivated and goal-directed behavior in schizophrenia.
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Affiliation(s)
- Deanna M Barch
- Department of Psychology, Washington University, Box 1125, One Brookings Drive, St. Louis, MO, USA.
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Barakauskas VE, Beasley CL, Barr AM, Ypsilanti AR, Li HY, Thornton AE, Wong H, Rosokilja G, Mann JJ, Mancevski B, Jakovski Z, Davceva N, Ilievski B, Dwork AJ, Falkai P, Honer WG. A novel mechanism and treatment target for presynaptic abnormalities in specific striatal regions in schizophrenia. Neuropsychopharmacology 2010; 35:1226-38. [PMID: 20072114 PMCID: PMC3055413 DOI: 10.1038/npp.2009.228] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2009] [Revised: 11/06/2009] [Accepted: 11/20/2009] [Indexed: 02/01/2023]
Abstract
Abnormalities of amount and function of presynaptic terminals may have an important role in the mechanism of illness in schizophrenia. The SNARE proteins (SNAP-25, syntaxin, and VAMP) are enriched in presynaptic terminals, where they interact to form a functional complex to facilitate vesicle fusion. SNARE protein amounts are altered in the cortical regions in schizophrenia, but studies of protein-protein interactions are limited. We extended these investigations to the striatal regions (such as the nucleus accumbens, ventromedial caudate (VMC), and dorsal caudate) relevant to disease symptoms. In addition to measuring SNARE protein levels, we studied SNARE protein-protein interactions using a novel ELISA method. The possible effect of antipsychotic treatment was investigated in parallel in the striatum of rodents that were administered haloperidol and clozapine. In schizophrenia samples, compared with controls, SNAP-25 was 32% lower (P=0.015) and syntaxin was 26% lower (P=0.006) in the VMC. In contrast, in the same region, SNARE protein-protein interactions were higher in schizophrenia (P=0.008). Confocal microscopy of schizophrenia and control VMC showed qualitatively similar SNARE protein immunostaining. Haloperidol treatment of rats increased levels of SNAP-25 (mean 24%, P=0.003), syntaxin (mean 18%, P=0.010), and VAMP (mean 16%, P=0.001), whereas clozapine increased only the VAMP level (mean 13%, P=0.004). Neither drug altered SNARE protein-protein interactions. These results indicate abnormalities of amount and interactions of proteins directly related to presynaptic function in the VMC in schizophrenia. SNARE proteins and their interactions may be a novel target for the development of therapeutics.
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Affiliation(s)
- Vilte E Barakauskas
- Department of Psychiatry, University of British Columbia, Vancouver, BC, Canada
| | - Clare L Beasley
- Department of Psychiatry, University of British Columbia, Vancouver, BC, Canada
| | - Alasdair M Barr
- Department of Anesthesiology, Pharmacology and Therapeutics, University of British Columbia, Vancouver, BC, Canada
| | - Athena R Ypsilanti
- Department of Psychiatry, University of British Columbia, Vancouver, BC, Canada
| | - Hong-Ying Li
- Department of Psychiatry, University of British Columbia, Vancouver, BC, Canada
| | - Allen E Thornton
- Department of Psychology, Simon Fraser University, Burnaby, BC, Canada
| | - Hubert Wong
- Department of Health Care and Epidemiology, University of British Columbia, Vancouver, BC, Canada
| | - Gorazd Rosokilja
- Department of Molecular Imaging and Neuropathology, New York State Psychiatric Institute, New York, NY, USA
- Department of Psychiatry, Surgeons of Columbia University, New York, NY, USA
- Macedonian Academy of Sciences and Arts, University ‘SS. Cyril and Methodius' Skopje, Macedonia
| | - J John Mann
- Department of Molecular Imaging and Neuropathology, New York State Psychiatric Institute, New York, NY, USA
- Department of Psychiatry, Surgeons of Columbia University, New York, NY, USA
| | - Branislav Mancevski
- Department of Molecular Imaging and Neuropathology, New York State Psychiatric Institute, New York, NY, USA
- Department of Psychiatry, Surgeons of Columbia University, New York, NY, USA
| | - Zlatko Jakovski
- Institute for Forensic Medicine, University ‘SS. Cyril and Methodius,' Skopje, Macedonia
| | - Natasha Davceva
- Institute for Forensic Medicine, University ‘SS. Cyril and Methodius,' Skopje, Macedonia
| | - Boro Ilievski
- Department of Molecular Imaging and Neuropathology, New York State Psychiatric Institute, New York, NY, USA
- Institute for Pathology, University ‘SS. Cyril and Methodius,', Skopje, Macedonia
| | - Andrew J Dwork
- Department of Molecular Imaging and Neuropathology, New York State Psychiatric Institute, New York, NY, USA
- Department of Psychiatry, Surgeons of Columbia University, New York, NY, USA
- Department of Pathology and Cell Biology, College of Physicians, Surgeons of Columbia University, New York, NY, USA
| | - Peter Falkai
- Department of Psychiatry, Göttingen University, Göttingen, Germany
| | - William G Honer
- Department of Psychiatry, University of British Columbia, Vancouver, BC, Canada
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Mansvelder HD, Mertz M, Role LW. Nicotinic modulation of synaptic transmission and plasticity in cortico-limbic circuits. Semin Cell Dev Biol 2009; 20:432-40. [PMID: 19560048 DOI: 10.1016/j.semcdb.2009.01.007] [Citation(s) in RCA: 91] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2008] [Revised: 01/11/2009] [Accepted: 01/13/2009] [Indexed: 11/19/2022]
Abstract
Nicotine is the principle addictive agent delivered via cigarette smoking. The addictive activity of nicotine is due to potent interactions with nicotinic acetylcholine receptors (nAChRs) on neurons in the reinforcement and reward circuits of the brain. Beyond its addictive actions, nicotine is thought to have positive effects on performance in working memory and short-term attention-related tasks. The brain areas involved in such behaviors are part of an extensive cortico-limbic network that includes relays between prefrontal cortex (PFC) and cingulate cortex (CC), hippocampus, amygdala, ventral tegmental area (VTA) and the nucleus accumbens (nAcc). Nicotine activates a broad array of nAChRs subtypes that can be targeted to pre- as well as peri- and post-synaptic locations in these areas. Thereby, nicotine not only excites different types of neurons, but it also perturbs baseline neuronal communication, alters synaptic properties and modulates synaptic plasticity. In this review we focus on recent findings on nicotinic modulation of cortical circuits and their targets fields, which show that acute and transient activation of nicotinic receptors in cortico-limbic circuits triggers a series of events that affects cognitive performance in a long lasting manner. Understanding how nicotine induces long-term changes in synapses and alters plasticity in the cortico-limbic circuits is essential to determining how these areas interact in decoding fundamental aspects of cognition and reward.
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Affiliation(s)
- Huibert D Mansvelder
- Department of Integrative Neurophysiology, Center for Neurogenomics and Cognitive Research (CNCR), VU University Amsterdam, Amsterdam, The Netherlands.
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A Subpopulation of Mesencephalic Dopamine Neurons Interfaces the Shell of Nucleus Accumbens and the Dorsolateral Striatum in Rats. ADVANCES IN BEHAVIORAL BIOLOGY 2009. [DOI: 10.1007/978-1-4419-0340-2_10] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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36
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Temporal patterns of motor behavioural improvements by MK-801 in Mongolian gerbils submitted to different duration of global cerebral ischemia. Behav Brain Res 2008; 194:72-8. [DOI: 10.1016/j.bbr.2008.06.031] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2008] [Revised: 06/17/2008] [Accepted: 06/20/2008] [Indexed: 01/09/2023]
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Inversion of dopamine responses in striatal medium spiny neurons and involuntary movements. J Neurosci 2008; 28:7537-47. [PMID: 18650331 DOI: 10.1523/jneurosci.1176-08.2008] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Dopamine influence in the striatum is essential to motor behavior and may lead to involuntary movements in pathologic conditions. The basic mechanisms lie in differential dopamine responses of medium spiny neurons (MSNs) contributing to striatal output pathways. The relationship between striatal discharge and mobility is thus critical to understanding the actions of dopamine. Using extracellular recordings in severely parkinsonian monkeys, we examined the activity changes of MSNs during different levels of dopamine stimulation. The activity of single MSNs was recorded continuously throughout conditions of parkinsonian disability, its reversal, and the exhibition of involuntary movements after levodopa administration. Parkinsonian disability was associated with robust and widely distributed increases of MSN firing. In the parkinsonian state, dopamine influx produced both increases and decreases in the discharge rate of MSNs. Furthermore, in contrast to the expected net reduction of activity, dopamine-induced recovery of mobility occurred with predominant further increases of neuronal activity. In contrast, involuntary movements were associated with a distinctive inversion of the dopamine responses. The activity increases and decreases associated with the recovery of mobility were subsequently inverted in a number of neurons, and these bidirectional changes created large differences of discharge across MSNs. Thus, a markedly dysregulated state of striatal activity develops after chronic dopamine denervation and, in such a state of MSN activity, dopamine induces altered and disproportionate responses. These findings point to the fundamental role of dopamine-mediated balance of striatal outputs for normal movement.
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Amphetamine exposure enhances accumbal responses to reward-predictive stimuli in a pavlovian conditioned approach task. J Neurosci 2008; 28:7501-12. [PMID: 18650328 DOI: 10.1523/jneurosci.1071-08.2008] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Acute and repeated exposure to psychostimulants such as amphetamine enhances the effects of pavlovian conditioned stimuli on conditioned behavior. It is hypothesized that amphetamine facilitates conditioned stimulus (CS) effects by selectively enhancing accumbal neuronal responses to stimuli. To test this hypothesis, rats were trained to discriminate between two pavlovian stimuli. One stimulus (i.e., CS+) was paired with sucrose delivery [i.e., unconditioned stimulus (US)], and the other stimulus (i.e., CS-) was paired with the absence of sucrose. Animals developed a conditioned approach response that occurred during the CS+ but not during the CS-. We tested the effect of different doses of amphetamine (0, 0.25, 0.5, or 1.0 mg/kg) on this conditioned approach behavior as well as on accumbal neuronal responses time locked to the CS+, the CS-, and the US. Acute amphetamine exposure increased conditioned approach behavior during the CS+, but not during the CS-. This change in behavior was associated with a selective increase in the magnitude of accumbal responses during the CS+. Repeated amphetamine administration followed by a drug-free period and reexposure did not affect the conditioned behavior, but increased accumbal responses to the CS+. These findings support the hypothesis that amphetamine exposure enhances behavioral responses to pavlovian conditioned stimuli by amplifying accumbal responses to those stimuli.
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Silvagni A, Barros VG, Mura C, Antonelli MC, Carboni E. Prenatal restraint stress differentially modifies basal and stimulated dopamine and noradrenaline release in the nucleus accumbens shell: an ‘in vivo’ microdialysis study in adolescent and young adult rats. Eur J Neurosci 2008; 28:744-58. [DOI: 10.1111/j.1460-9568.2008.06364.x] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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40
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Robinson DL, Hermans A, Seipel AT, Wightman RM. Monitoring rapid chemical communication in the brain. Chem Rev 2008; 108:2554-84. [PMID: 18576692 PMCID: PMC3110685 DOI: 10.1021/cr068081q] [Citation(s) in RCA: 454] [Impact Index Per Article: 28.4] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Affiliation(s)
- Donita L Robinson
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, USA
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41
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Ondracek JM, Dec A, Hoque KE, Lim SAO, Rasouli G, Indorkar RP, Linardakis J, Klika B, Mukherji SJ, Burnazi M, Threlfell S, Sammut S, West AR. Feed-forward excitation of striatal neuron activity by frontal cortical activation of nitric oxide signaling in vivo. Eur J Neurosci 2008; 27:1739-54. [PMID: 18371082 DOI: 10.1111/j.1460-9568.2008.06157.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The gaseous neurotransmitter nitric oxide plays an important role in the modulation of corticostriatal synaptic transmission. This study examined the impact of frontal cortex stimulation on striatal nitric oxide efflux and neuron activity in urethane-anesthetized rats using amperometric microsensor and single-unit extracellular recordings, respectively. Systemic administration of the neuronal nitric oxide synthase inhibitor 7-nitroindazole decreased spontaneous spike activity without affecting activity evoked by single-pulse stimulation of the ipsilateral cortex. Train (30 Hz) stimulation of the contralateral frontal cortex transiently increased nitric oxide efflux in a robust and reproducible manner. Evoked nitric oxide efflux was attenuated by systemic administration of 7-nitroindazole and the non-selective nitric oxide synthase inhibitor N(G)-nitro-L-arginine methyl ester. Train stimulation of the contralateral cortex, in a manner identical to that used to evoke nitric oxide efflux, had variable effects on spike activity assessed during the train stimulation trial, but induced a short-term depression of cortically evoked activity in the first post-train stimulation trial. Interestingly, 7-nitroindazole potently decreased cortically evoked activity recorded during the train stimulation trial. Moreover, the short-term depression of spike activity induced by train stimulation was enhanced following pretreatment with 7-nitroindazole and attenuated after systemic administration of the dopamine D2 receptor antagonist eticlopride. These results demonstrate that robust activation of frontal cortical afferents in the intact animal activates a powerful nitric oxide-mediated feed-forward excitation which partially offsets concurrent D2 receptor-mediated short-term inhibitory influences on striatal neuron activity. Thus, nitric oxide signaling is likely to play an important role in the integration of corticostriatal sensorimotor information in striatal networks.
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Affiliation(s)
- Janie M Ondracek
- The Chicago Medical School at Rosalind Franklin University of Medicine and Science, Department of Neuroscience, 3333 Green Bay Road, North Chicago, IL 60064, USA
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Rodrigues TB, Granado N, Ortiz O, Cerdán S, Moratalla R. Metabolic interactions between glutamatergic and dopaminergic neurotransmitter systems are mediated through D(1) dopamine receptors. J Neurosci Res 2008; 85:3284-93. [PMID: 17455302 DOI: 10.1002/jnr.21302] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Interactions between the dopaminergic and glutamatergic neurotransmission systems were investigated in the adult brain of wild-type (WT) and transgenic mice lacking the dopamine D(1) or D(2) receptor subtypes. Activity of the glutamine cycle was evaluated by using (13)C NMR spectroscopy, and striatal activity was assessed by c-Fos expression and motor coordination. Brain extracts from (1,2-(13)C(2)) acetate-infused mice were prepared and analyzed by (13)C NMR to determine the incorporation of the label into the C4 and C5 carbons of glutamate and glutamine. D(1)R(-/-) mice showed a significantly higher concentration of cerebral (4,5-(13)C(2)) glutamine, consistent with an increased activity of the glutamate-glutamine cycle and of glutamatergic neurotransmission. Conversely, D(2)R(-/-) mice did not show any significant changes in (4,5-(13)C(2)) glutamate or (4,5-(13)C(2)) glutamine, suggesting that alterations in glutamine metabolism are mediated through D(1) receptors. This was confirmed with D(1)R(-/-) and WT mice treated with reserpine, a dopamine-depleting drug, or with reserpine followed by L-DOPA, a dopamine precursor. Exposure to reserpine increased (4,5-(13)C(2)) glutamine in WT to levels similar to those found in untreated D(1)R(-/-) mice. These values were the same as those reached in the reserpine-treated D(1)R(-/-) mice. Treatment of WT animals with L-DOPA returned (4,5-(13)C(2)) glutamine levels to normal, but this was not verified in D(1)R(-/-) animals. Reserpine impaired motor coordination and decreased c-Fos expression, whereas L-DOPA restored both variables to normal values in WT but not in D(1)R(-/-). Together, our results reveal novel neurometabolic interactions between glutamatergic and dopaminergic systems that are mediated through the D(1), but not the D(2), dopamine receptor subtype.
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Affiliation(s)
- Tiago B Rodrigues
- Instituto de Investigaciones Biomédicas Alberto Sols, CSIC/UAM, Madrid, Spain
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Peterson BS, Choi HA, Hao X, Amat JA, Zhu H, Whiteman R, Liu J, Xu D, Bansal R. Morphologic features of the amygdala and hippocampus in children and adults with Tourette syndrome. ACTA ACUST UNITED AC 2007; 64:1281-91. [PMID: 17984397 DOI: 10.1001/archpsyc.64.11.1281] [Citation(s) in RCA: 110] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
CONTEXT Limbic portions of cortical-subcortical circuits are likely involved in the pathogenesis of Tourette syndrome (TS). They are anatomically, developmentally, neurochemically, and functionally related to the basal ganglia, and the basal ganglia are thought to produce the symptoms of tics, obsessive-compulsive disorder, and attention-deficit/hyperactivity disorder that commonly affect persons with TS. OBJECTIVE To study the morphologic features of the hippocampus and amygdala in children and adults with TS. DESIGN A cross-sectional, case-control study using anatomical magnetic resonance imaging. SETTING University research center. PARTICIPANTS A total of 282 individuals (154 patients with TS and 128 controls) aged 6 to 63 years. MAIN OUTCOME MEASURES Volumes and measures of surface morphologic features of the hippocampus and amygdala. RESULTS The overall volumes of the hippocampus and amygdala were significantly larger in the TS group. Surface analyses suggested that the increased volumes in the TS group derived primarily from the head and medial surface of the hippocampus (over the length of the dentate gyrus) and the dorsal and ventral surfaces of the amygdala (over its basolateral and central nuclei). Volumes of these subregions declined with age in the TS group but not in controls, so the subregions were significantly larger in children with TS but significantly smaller in adults with TS than in their control counterparts. In children and adults, volumes in these subregions correlated inversely with the severity of tic, obsessive-compulsive disorder, and attention-deficit/hyperactivity disorder symptoms, suggesting that enlargement of the subregions may have a compensatory and neuromodulatory effect on tic-related symptoms. CONCLUSION These findings are consistent with the known plasticity of the dentate gyrus and with findings from previous imaging studies suggesting the presence of failed compensatory plasticity in adults with TS who have not experienced the usual decline in symptoms during adolescence.
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Affiliation(s)
- Bradley S Peterson
- Columbia College of Physicians and Surgeons and New York State Psychiatric Institute, 1051 Riverside Dr, Unit 74, New York, NY 10032, USa.
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Alcaro A, Huber R, Panksepp J. Behavioral functions of the mesolimbic dopaminergic system: an affective neuroethological perspective. BRAIN RESEARCH REVIEWS 2007; 56:283-321. [PMID: 17905440 PMCID: PMC2238694 DOI: 10.1016/j.brainresrev.2007.07.014] [Citation(s) in RCA: 295] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2006] [Revised: 07/03/2007] [Accepted: 07/03/2007] [Indexed: 12/11/2022]
Abstract
The mesolimbic dopaminergic (ML-DA) system has been recognized for its central role in motivated behaviors, various types of reward, and, more recently, in cognitive processes. Functional theories have emphasized DA's involvement in the orchestration of goal-directed behaviors and in the promotion and reinforcement of learning. The affective neuroethological perspective presented here views the ML-DA system in terms of its ability to activate an instinctual emotional appetitive state (SEEKING) evolved to induce organisms to search for all varieties of life-supporting stimuli and to avoid harms. A description of the anatomical framework in which the ML system is embedded is followed by the argument that the SEEKING disposition emerges through functional integration of ventral basal ganglia (BG) into thalamocortical activities. Filtering cortical and limbic input that spreads into BG, DA transmission promotes the "release" of neural activity patterns that induce active SEEKING behaviors when expressed at the motor level. Reverberation of these patterns constitutes a neurodynamic process for the inclusion of cognitive and perceptual representations within the extended networks of the SEEKING urge. In this way, the SEEKING disposition influences attention, incentive salience, associative learning, and anticipatory predictions. In our view, the rewarding properties of drugs of abuse are, in part, caused by the activation of the SEEKING disposition, ranging from appetitive drive to persistent craving depending on the intensity of the affect. The implications of such a view for understanding addiction are considered, with particular emphasis on factors predisposing individuals to develop compulsive drug seeking behaviors.
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Affiliation(s)
- Antonio Alcaro
- Department of Biological Sciences and J.P. Scott Center for Neuroscience, Mind & Behavior, Bowling Green State University, Life Science Building, Bowling Green, OH, 43403, USA
- Santa Lucia Foundation, European Centre for Brain Research (CERC), Via del Fosso di Fiorano 65, 00143 Rome, Italy
| | - Robert Huber
- Department of Biological Sciences and J.P. Scott Center for Neuroscience, Mind & Behavior, Bowling Green State University, Life Science Building, Bowling Green, OH, 43403, USA
| | - Jaak Panksepp
- Department of Biological Sciences and J.P. Scott Center for Neuroscience, Mind & Behavior, Bowling Green State University, Life Science Building, Bowling Green, OH, 43403, USA
- Department of VCAPP, Center for the Study of Animal Well-Being, College of Veterinary Medicine, Washington State University, Pullman, WA 99163, USA
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Mora F, Segovia G, Del Arco A. Glutamate-dopamine-GABA interactions in the aging basal ganglia. ACTA ACUST UNITED AC 2007; 58:340-53. [PMID: 18036669 DOI: 10.1016/j.brainresrev.2007.10.006] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2007] [Revised: 10/05/2007] [Accepted: 10/06/2007] [Indexed: 12/25/2022]
Abstract
The study of neurotransmitter interactions gives a better understanding of the physiology of specific circuits in the brain. In this review we focus mostly on our own results on the interaction of the neurotransmitters glutamate, dopamine and GABA in the basal ganglia during the normal process of aging. We review first the studies on the action of endogenous glutamate on the extracellular concentrations of dopamine and GABA in the neostriatum and nucleus accumbens during aging. It was found that there exists an age-related change in the interaction of glutamate, dopamine and GABA and that these effects of aging exhibit a dorsal-to-ventral pattern of effects with no changes in the dorsal parts (dorsal striatum) and changes in the most ventral parts (nucleus accumbens). Second we reviewed the data on the effects of different ionotropic and metabotropic glutamate receptor agonists on the extracellular concentrations of dopamine and GABA in the nucleus accumbens. The results obtained clearly show the different contribution of each glutamate receptor subtype in the age-related changes produced on the interaction of glutamate, dopamine and GABA in this area of the brain. Third the effects of an enriched environment on the action of AMPA and NMDA-receptor agonists in the nucleus accumbens of rats during aging are also evaluated. Finally, and since the nucleus accumbens has been suggested to play a role in emotion and motivation and also motor behaviour, we speculated on the possibility of a specific contribution for the different glutamatergic pathways terminating in the nucleus accumbens and their interaction with a decreased dopamine playing a relevant role in motor behaviour during aging.
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Affiliation(s)
- Francisco Mora
- Department of Physiology, Faculty of Medicine, Universidad Complutense, Ciudad Universitaria, s/n 28040 Madrid, Spain.
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46
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Brooks JM, Sarter M, Bruno JP. D2-like receptors in nucleus accumbens negatively modulate acetylcholine release in prefrontal cortex. Neuropharmacology 2007; 53:455-63. [PMID: 17681559 PMCID: PMC2000917 DOI: 10.1016/j.neuropharm.2007.06.006] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2007] [Revised: 05/25/2007] [Accepted: 06/03/2007] [Indexed: 11/26/2022]
Abstract
Glutamatergic and dopaminergic inputs converge on medium spiny neurons in nucleus accumbens and regulate the excitability of these projections to target areas including the cholinergic basal forebrain. NMDA receptors situated on these projections are locally modulated by D1- and D2-like receptors. We previously reported that the D1-like positive modulation of NMDA receptor activity is expressed trans-synaptically in the control of basal forebrain cholinergic projections to prefrontal cortex. The present experiments tested the hypothesis that D2-like receptors in accumbens negatively modulate cortical ACh release. Perfusion of NMDA (150 microM) into the shell region of the accumbens produced a sustained increase (150-200%) in ACh release in prefrontal cortex. This increase was completely blocked by co-perfusion with the D2-like agonist quinpirole (100 microM). Perfusion of quinpirole also reduced basal ACh release (approximately 50%) in prefrontal cortex. The contribution of D2 receptors to the quinpirole effect was assessed in two additional studies. The first study revealed that co-perfusion of the D2 antagonist haloperidol (100 microM) blocked the quinpirole-induced attenuation of NMDA mediated ACh release. The second experiment demonstrated that intra-accumbens perfusion of quinelorane (100 microM), a more selective D2 agonist than quinpirole, also attenuated the NMDA mediated ACh release. Collectively, these studies demonstrate that D2 receptors in accumbens negatively modulate basal and NMDA mediated increases in ACh release in prefrontal cortex. This negative modulation may contribute to the integration of normal attentional processing and goal directed behavior and to the therapeutic effects of antipsychotic medication on cognition in psychopathologies such as schizophrenia.
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Affiliation(s)
| | | | - John P. Bruno
- Department of Psychology, The Ohio State University
- Department of Neuroscience, The Ohio State University
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Fadda P, Bedogni F, Fresu A, Collu M, Racagni G, Riva MA. Reduction of corticostriatal glutamatergic fibers in basic fibroblast growth factor deficient mice is associated with hyperactivity and enhanced dopaminergic transmission. Biol Psychiatry 2007; 62:235-42. [PMID: 17161387 DOI: 10.1016/j.biopsych.2006.08.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2006] [Revised: 07/19/2006] [Accepted: 08/09/2006] [Indexed: 11/18/2022]
Abstract
BACKGROUND Basic fibroblast growth factor (FGF2) plays a crucial role during the development of the cerebral cortex. Mice with a knockout of the FGF2 gene have a reduced number of glutamatergic neurons within the deep layers of the cerebral cortex. METHODS We used molecular and behavioral analyses to investigate possible alterations in corticostriatal function in FGF2 -/- mice. RESULTS We found that FGF2 deficiency leads to decreased expression of presynaptic markers of integrity for glutamatergic fibers in the striatum, namely the membrane excitatory amino acid transporter 3 (EAAT3) and the vesicular glutamate transporter 1 (VGLUT1). The reduction of corticostriatal glutamatergic function in FGF2 -/- mice is associated with enhanced locomotor activity in a novel environment and increased responsiveness to dopaminergic drugs, such as cocaine or amphetamine. The behavioral alterations of FGF2 -/- can be normalized by injection of a low dose of the dopaminergic agonist apomorphine (.1 mg/kg) that reduces dopamine release by acting on presynaptic receptors. CONCLUSIONS Our data demonstrate that FGF2 -/- mice have an increased tone and responsiveness of the dopaminergic system and suggest that these animals might represent a model to study disorders that are characterized by an imbalance between glutamatergic and dopaminergic neurotransmission.
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Affiliation(s)
- Paola Fadda
- Department of Neuroscience B.B. Brodie, Center for Excellence in Neurobiology of Dependence, University of Cagliari, Cittadella Universitaria, Monserrato, Italy
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Thivierge JP, Rivest F, Monchi O. Spiking neurons, dopamine, and plasticity: timing is everything, but concentration also matters. Synapse 2007; 61:375-90. [PMID: 17372980 DOI: 10.1002/syn.20378] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
While both dopamine (DA) fluctuations and spike-timing-dependent plasticity (STDP) are known to influence long-term corticostriatal plasticity, little attention has been devoted to the interaction between these two fundamental mechanisms. Here, a theoretical framework is proposed to account for experimental results specifying the role of presynaptic activation, postsynaptic activation, and concentrations of extracellular DA in synaptic plasticity. Our starting point was an explicitly-implemented multiplicative rule linking STDP to Michaelis-Menton equations that models the dynamics of extracellular DA fluctuations. This rule captures a wide range of results on conditions leading to long-term potentiation and depression in simulations that manipulate the frequency of induced corticostriatal stimulation and DA release. A well-documented biphasic function relating DA concentrations to synaptic plasticity emerges naturally from simulations involving a multiplicative rule linking DA and neural activity. This biphasic function is found consistently across different neural coding schemes employed (voltage-based vs. spike-based models). By comparison, an additive rule fails to capture these results. The proposed framework is the first to generate testable predictions on the dual influence of DA concentrations and STDP on long-term plasticity, suggesting a way in which the biphasic influence of DA concentrations can modulate the direction and magnitude of change induced by STDP, and raising the possibility that DA concentrations may inverse the LTP/LTD components of the STDP rule.
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Pilo Boyl P, Di Nardo A, Mulle C, Sassoè-Pognetto M, Panzanelli P, Mele A, Kneussel M, Costantini V, Perlas E, Massimi M, Vara H, Giustetto M, Witke W. Profilin2 contributes to synaptic vesicle exocytosis, neuronal excitability, and novelty-seeking behavior. EMBO J 2007; 26:2991-3002. [PMID: 17541406 PMCID: PMC1894775 DOI: 10.1038/sj.emboj.7601737] [Citation(s) in RCA: 110] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2006] [Accepted: 05/03/2007] [Indexed: 11/08/2022] Open
Abstract
Profilins are actin binding proteins essential for regulating cytoskeletal dynamics, however, their function in the mammalian nervous system is unknown. Here, we provide evidence that in mouse brain profilin1 and profilin2 have distinct roles in regulating synaptic actin polymerization with profilin2 preferring a WAVE-complex-mediated pathway. Mice lacking profilin2 show a block in synaptic actin polymerization in response to depolarization, which is accompanied by increased synaptic excitability of glutamatergic neurons due to higher vesicle exocytosis. These alterations in neurotransmitter release correlate with a hyperactivation of the striatum and enhanced novelty-seeking behavior in profilin2 mutant mice. Our results highlight a novel, profilin2-dependent pathway, regulating synaptic physiology, neuronal excitability, and complex behavior.
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Affiliation(s)
| | | | - Christophe Mulle
- UMR CNRS 5091, Institut François Magendie, Physiologie Cellulaire de la Synapse, Bordeaux, France
| | - Marco Sassoè-Pognetto
- Department of Anatomy, Pharmacology and Forensic Medicine and Istituto Nazionale di Neuroscienze, University of Turin, Torino, Italy
| | - Patrizia Panzanelli
- Department of Anatomy, Pharmacology and Forensic Medicine and Istituto Nazionale di Neuroscienze, University of Turin, Torino, Italy
| | - Andrea Mele
- Università di Roma ‘La Sapienza', Laboratorio di Psicobiologia, Dipart. di Genetica e Biologia Molecolare, Roma, Italy
| | - Matthias Kneussel
- Centre for Molecular Neurobiology, ZMNH, University of Hamburg, Hamburg, Germany
| | - Vivian Costantini
- Università di Roma ‘La Sapienza', Laboratorio di Psicobiologia, Dipart. di Genetica e Biologia Molecolare, Roma, Italy
| | | | | | - Hugo Vara
- Department of Anatomy, Pharmacology and Forensic Medicine and Istituto Nazionale di Neuroscienze, University of Turin, Torino, Italy
| | - Maurizio Giustetto
- Department of Anatomy, Pharmacology and Forensic Medicine and Istituto Nazionale di Neuroscienze, University of Turin, Torino, Italy
| | - Walter Witke
- EMBL, Mouse Biology Unit, Monterotondo, Italy
- EMBL, Mouse Biology Unit, Adriano Buzzati-Traverso Campus, Via Ramarini 32, 00015 Monterotondo, Italy. Tel.: +0039 06 90091 268; Fax: +0039 06 90091 272; E-mail:
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Chambers RA, Bickel WK, Potenza MN. A scale-free systems theory of motivation and addiction. Neurosci Biobehav Rev 2007; 31:1017-45. [PMID: 17574673 PMCID: PMC2150750 DOI: 10.1016/j.neubiorev.2007.04.005] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2006] [Revised: 04/03/2007] [Accepted: 04/09/2007] [Indexed: 11/24/2022]
Abstract
Scale-free organizations, characterized by uneven distributions of linkages between nodal elements, describe the structure and function of many life-based complex systems developing under evolutionary pressures. We explore motivated behavior as a scale-free map toward a comprehensive translational theory of addiction. Motivational and behavioral repertoires are reframed as link and nodal element sets, respectively, comprising a scale-free structure. These sets are generated by semi-independent information-processing streams within cortical-striatal circuits that cooperatively provide decision-making and sequential processing functions necessary for traversing maps of motivational links connecting behavioral nodes. Dopamine modulation of cortical-striatal plasticity serves a central-hierarchical mechanism for survival-adaptive sculpting and development of motivational-behavioral repertoires by guiding a scale-free design. Drug-induced dopamine activity promotes drug taking as a highly connected behavioral hub at the expense of natural-adaptive motivational links and behavioral nodes. Conceptualizing addiction as pathological alteration of scale-free motivational-behavioral repertoires unifies neurobiological, neurocomputational and behavioral research while addressing addiction vulnerability in adolescence and psychiatric illness. This model may inform integrative research in defining more effective prevention and treatment strategies for addiction.
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Affiliation(s)
- R. Andrew Chambers
- Assistant Professor of Psychiatry, Director, Laboratory for Translational Neuroscience of Dual Diagnosis Disorders, Institute of Psychiatric Research, Assistant Medical Director, Indiana Division of Mental Health and Addiction, Indiana University School of Medicine, 791 Union Drive, Indianapolis, IN 46202, Ph: (317) 278-1716, Fax: (317) 274-1365,
| | - Warren K. Bickel
- Professor of Psychiatry, Wilbur D. Mills Chair of Alcoholism and Drug Abuse Prevention, Director, Center for Addiction Research, College of Medicine, Director, Center for the Study of Tobacco, Fay W Boozeman College of Public Health, University of Arkansas for Medical Sciences, Little Rock, AR,
| | - Marc N. Potenza
- Associate Professor of Psychiatry, Director, Problem Gambling Clinic at Yale, Director, Women and Addictions Core of Women’s Health Research at Yale, Director of Neuroimaging, MIRECC VISN1, West Haven Veteran’s Administration Hospital, Yale University School of Medicine, New Haven, CT,
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