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Pasquini J, Brooks DJ, Pavese N. The Cholinergic Brain in Parkinson's Disease. Mov Disord Clin Pract 2021; 8:1012-1026. [PMID: 34631936 DOI: 10.1002/mdc3.13319] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Revised: 07/07/2021] [Accepted: 07/22/2021] [Indexed: 02/06/2023] Open
Abstract
The central cholinergic system includes the basal forebrain nuclei, mainly projecting to the cortex, the mesopontine tegmental nuclei, mainly projecting to the thalamus and subcortical structures, and other groups of projecting neurons and interneurons. This system regulates many functions of human behavior such as cognition, locomotion, and sleep. In Parkinson's disease (PD), disruption of central cholinergic transmission has been associated with cognitive decline, gait problems, freezing of gait (FOG), falls, REM sleep behavior disorder (RBD), neuropsychiatric manifestations, and olfactory dysfunction. Neuropathological and neuroimaging evidence suggests that basal forebrain pathology occurs simultaneously with nigrostriatal denervation, whereas pathology in the pontine nuclei may occur before the onset of motor symptoms. These studies have also detailed the clinical implications of cholinergic dysfunction in PD. Degeneration of basal forebrain nuclei and consequential cortical cholinergic denervation are associated with and may predict the subsequent development of cognitive decline and neuropsychiatric symptoms. Gait problems, FOG, and falls are associated with a complex dysfunction of both pontine and basal forebrain nuclei. Olfactory impairment is associated with cholinergic denervation of the limbic archicortex, specifically hippocampus and amygdala. Available evidence suggests that cholinergic dysfunction, alongside failure of the dopaminergic and other neurotransmitters systems, contributes to the generation of a specific set of clinical manifestations. Therefore, a "cholinergic phenotype" can be identified in people presenting with cognitive decline, falls, and RBD. In this review, we will summarize the organization of the central cholinergic system and the clinical correlates of cholinergic dysfunction in PD.
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Affiliation(s)
- Jacopo Pasquini
- Department of Pathophysiology and Transplantation University of Milan Milan Italy.,Clinical Ageing Research Unit Newcastle University Newcastle upon Tyne United Kingdom
| | - David J Brooks
- Positron Emission Tomography Centre Newcastle University Newcastle upon Tyne United Kingdom.,Department of Nuclear Medicine and PET Centre Aarhus University Hospital Aarhus Denmark
| | - Nicola Pavese
- Clinical Ageing Research Unit Newcastle University Newcastle upon Tyne United Kingdom.,Department of Nuclear Medicine and PET Centre Aarhus University Hospital Aarhus Denmark
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Horie S, Kiyokage E, Hayashi S, Inoue K, Sohn J, Hioki H, Furuta T, Toida K. Structural basis for noradrenergic regulation of neural circuits in the mouse olfactory bulb. J Comp Neurol 2021; 529:2189-2208. [PMID: 33616936 DOI: 10.1002/cne.25085] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 11/19/2020] [Accepted: 11/29/2020] [Indexed: 11/09/2022]
Abstract
Olfactory input is processed in the glomerulus of the main olfactory bulb (OB) and relayed to higher centers in the brain by projection neurons. Conversely, centrifugal inputs from other brain regions project to the OB. We have previously analyzed centrifugal inputs into the OB from several brain regions using single-neuron labeling. In this study, we analyzed the centrifugal noradrenergic (NA) fibers derived from the locus coeruleus (LC), because their projection pathways and synaptic connections in the OB have not been clarified in detail. We analyzed the NA centrifugal projections by single-neuron labeling and immunoelectron microscopy. Individual NA neurons labeled by viral infection were three-dimensionally traced using Neurolucida software to visualize the projection pathway from the LC to the OB. Also, centrifugal NA fibers were visualized using an antibody for noradrenaline transporter (NET). NET immunoreactive (-ir) fibers contained many varicosities and synaptic vesicles. Furthermore, electron tomography demonstrated that NET-ir fibers formed asymmetrical synapses of varied morphology. Although these synapses were present at varicosities, the density of synapses was relatively low throughout the OB. The maximal density of synapses was found in the external plexiform layer; about 17% of all observed varicosities contained synapses. These results strongly suggest that NA-containing fibers in the OB release NA from both varicosities and synapses to influence the activities of OB neurons. The present study provides a morphological basis for olfactory modulation by centrifugal NA fibers derived from the LC.
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Affiliation(s)
- Sawa Horie
- Department of Anatomy, Kawasaki Medical School, Kurashiki, Okayama, Japan
| | - Emi Kiyokage
- Department of Medical Technology, Faculty of Health Science and Technology, Kawasaki University of Medical Welfare, Kurashiki, Okayama, Japan
| | - Shuichi Hayashi
- Department of Anatomy, Kawasaki Medical School, Kurashiki, Okayama, Japan
| | - Kanako Inoue
- Research Center for Ultra-High Voltage Electron Microscopy, Osaka University, Osaka, Japan
| | - Jaerin Sohn
- Division of Cerebral Circuitry, National Institute for Physiological Sciences, Okazaki, Aichi, Japan
| | - Hiroyuki Hioki
- Department of Cell Biology and Neuroscience, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Takahiro Furuta
- Department of Oral Anatomy and Neurobiology, Osaka University Graduate School of Dentistry, Osaka, Japan
| | - Kazunori Toida
- Department of Anatomy, Kawasaki Medical School, Kurashiki, Okayama, Japan.,Research Center for Ultra-High Voltage Electron Microscopy, Osaka University, Osaka, Japan
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Wilson H, de Natale ER, Politis M. Nucleus basalis of Meynert degeneration predicts cognitive impairment in Parkinson's disease. HANDBOOK OF CLINICAL NEUROLOGY 2021; 179:189-205. [DOI: 10.1016/b978-0-12-819975-6.00010-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/07/2023]
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Lee DJ, Milosevic L, Gramer R, Sasikumar S, Al-Ozzi TM, De Vloo P, Dallapiazza RF, Elias GJB, Cohn M, Kalia SK, Hutchison WD, Fasano A, Lozano AM. Nucleus basalis of Meynert neuronal activity in Parkinson's disease. J Neurosurg 2020; 132:574-582. [PMID: 30797189 DOI: 10.3171/2018.11.jns182386] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Accepted: 11/02/2018] [Indexed: 11/06/2022]
Abstract
OBJECTIVE Neuronal loss within the cholinergic nucleus basalis of Meynert (nbM) correlates with cognitive decline in dementing disorders such as Alzheimer's disease and Parkinson's disease (PD). In nonhuman primates, the nbM firing pattern (5-40 Hz) has also been correlated with working memory and sustained attention. In this study, authors performed microelectrode recordings of the globus pallidus pars interna (GPi) and the nbM immediately prior to the implantation of bilateral deep brain stimulation (DBS) electrodes in PD patients to treat motor symptoms and cognitive impairment, respectively. Here, the authors evaluate the electrophysiological properties of the nbM in patients with PD. METHODS Five patients (4 male, mean age 66 ± 4 years) with PD and mild cognitive impairment underwent bilateral GPi and nbM DBS lead implantation. Microelectrode recordings were performed through the GPi and nbM along a single trajectory. Firing rates and burst indices were characterized for each neuronal population with the patient at rest and performing a sustained-attention auditory oddball task. Action potential (AP) depolarization and repolarization widths were measured for each neuronal population at rest. RESULTS In PD patients off medication, the authors identified neuronal discharge rates that were specific to each area populated by GPi cells (92.6 ± 46.1 Hz), border cells (34 ± 21 Hz), and nbM cells (13 ± 10 Hz). During the oddball task, firing rates of nbM cells decreased (2.9 ± 0.9 to 2.0 ± 1.1 Hz, p < 0.05). During baseline recordings, the burst index for nbM cells (1.7 ± 0.6) was significantly greater than those for GPi cells (1.2 ± 0.2, p < 0.05) and border cells (1.1 ± 0.1, p < 0.05). There was no significant difference in the nbM burst index during the oddball task relative to baseline (3.4 ± 1.7, p = 0.20). With the patient at rest, the width of the depolarization phase of APs did not differ among the GPi cells, border cells, and nbM cells (p = 0.60); however, during the repolarization phase, the nbM spikes were significantly longer than those for GPi high-frequency discharge cells (p < 0.05) but not the border cells (p = 0.20). CONCLUSIONS Neurons along the trajectory through the GPi and nbM have distinct firing patterns. The profile of nbM activity is similar to that observed in nonhuman primates and is altered during a cognitive task associated with cholinergic activation. These findings will serve to identify these targets intraoperatively and form the basis for further research to characterize the role of the nbM in cognition.
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Affiliation(s)
- Darrin J Lee
- Departments of1Neurological Surgery
- 6Krembil Research Institute, Toronto, Ontario, Canada
| | - Luka Milosevic
- 2Institute of Biomaterials and Biomedical Engineering, University of Toronto; and
- 6Krembil Research Institute, Toronto, Ontario, Canada
| | - Robert Gramer
- Departments of1Neurological Surgery
- 6Krembil Research Institute, Toronto, Ontario, Canada
| | | | - Tameem M Al-Ozzi
- 4Physiology, and
- 6Krembil Research Institute, Toronto, Ontario, Canada
| | - Philippe De Vloo
- Departments of1Neurological Surgery
- 6Krembil Research Institute, Toronto, Ontario, Canada
| | - Robert F Dallapiazza
- Departments of1Neurological Surgery
- 6Krembil Research Institute, Toronto, Ontario, Canada
| | - Gavin J B Elias
- Departments of1Neurological Surgery
- 6Krembil Research Institute, Toronto, Ontario, Canada
| | - Melanie Cohn
- 5Psychology
- 6Krembil Research Institute, Toronto, Ontario, Canada
| | - Suneil K Kalia
- Departments of1Neurological Surgery
- 6Krembil Research Institute, Toronto, Ontario, Canada
| | | | - Alfonso Fasano
- 3Neurology
- 6Krembil Research Institute, Toronto, Ontario, Canada
| | - Andres M Lozano
- Departments of1Neurological Surgery
- 6Krembil Research Institute, Toronto, Ontario, Canada
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Reid GA, Geula C, Darvesh S. The cholinergic system in the basal forebrain of the Atlantic white-sided dolphin (Lagenorhynchus acutus). J Comp Neurol 2018; 526:1910-1926. [PMID: 29700823 DOI: 10.1002/cne.24460] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Revised: 04/05/2018] [Accepted: 04/17/2018] [Indexed: 11/12/2022]
Abstract
The basal forebrain (BFB) cholinergic neurotransmitter system is important in a number of brain functions including attention, memory, and the sleep-wake cycle. The size of this region has been linked to the increase in encephalization of the brain in a number of species. Cetaceans, particularly those belonging to the family Delphinidae, have a relatively large brain compared to its body size and it is expected that the cholinergic BFB in the dolphin would be a prominent feature. However, this has not yet been explored in detail. This study examines and maps the neuroanatomy and cholinergic chemoarchitecture of the BFB in the Atlantic white-sided dolphin (Lagenorhynchus acutus). As in some other mammals, the BFB in this species is a prominent structure along the medioventral surface of the brain. The parcellation and distribution of cholinergic neural elements of the dolphin BFB was comparable to that observed in other mammals in that it has a medial septal nucleus, a nucleus of the vertical limb of the diagonal band of Broca, a nucleus of the horizontal limb of the diagonal band of Broca, and a nucleus basalis of Meynert. The observed BFB cholinergic system of this dolphin is consistent with evolutionarily conserved and important functions for survival.
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Affiliation(s)
- George Andrew Reid
- Department of Medical Neuroscience, Halifax, Dalhousie University, Nova Scotia, Canada.,Marine Animal Response Society, Halifax, Nova Scotia, Canada
| | - Changiz Geula
- Cognitive Neurology and Alzheimer's Disease Center, Northwestern University, Feinberg School of Medicine, Chicago, Illinois
| | - Sultan Darvesh
- Department of Medical Neuroscience, Halifax, Dalhousie University, Nova Scotia, Canada.,Department of Medicine (Neurology and Geriatric Medicine), Dalhousie University, Halifax, Nova Scotia, Canada
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Pope CN, Brimijoin S. Cholinesterases and the fine line between poison and remedy. Biochem Pharmacol 2018; 153:205-216. [PMID: 29409903 PMCID: PMC5959757 DOI: 10.1016/j.bcp.2018.01.044] [Citation(s) in RCA: 74] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Accepted: 01/26/2018] [Indexed: 12/20/2022]
Abstract
Acetylcholinesterase (AChE, EC 3.1.1.7) and butyrylcholinesterase (BChE, EC 3.1.1.8) are related enzymes found across the animal kingdom. The critical role of acetylcholinesterase in neurotransmission has been known for almost a century, but a physiological role for butyrylcholinesterase is just now emerging. The cholinesterases have been deliberately targeted for both therapy and toxicity, with cholinesterase inhibitors being used in the clinic for a variety of disorders and conversely for their toxic potential as pesticides and chemical weapons. Non-catalytic functions of the cholinesterases (ChEs) participate in both neurodevelopment and disease. Manipulating either the catalytic activities or the structure of these enzymes can potentially shift the balance between beneficial and adverse effect in a wide number of physiological processes.
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Affiliation(s)
- Carey N Pope
- Department of Physiological Sciences, Interdisciplinary Toxicology Program, Oklahoma State University, Stillwater, OK 74078, USA.
| | - Stephen Brimijoin
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN 55902, USA
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Lénárd L, László K, Kertes E, Ollmann T, Péczely L, Kovács A, Kállai V, Zagorácz O, Gálosi R, Karádi Z. Substance P and neurotensin in the limbic system: Their roles in reinforcement and memory consolidation. Neurosci Biobehav Rev 2018; 85:1-20. [DOI: 10.1016/j.neubiorev.2017.09.003] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Revised: 08/24/2017] [Accepted: 09/02/2017] [Indexed: 12/18/2022]
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Mongia S, Tripathi A, Mengual E. Arborization patterns of amygdalopetal axons from the rat ventral pallidum. Brain Struct Funct 2016; 221:4549-4573. [PMID: 26832919 DOI: 10.1007/s00429-016-1184-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Accepted: 01/07/2016] [Indexed: 10/22/2022]
Abstract
We previously analyzed the arborization patterns of rat ventral pallidal (VP) axons that coursed caudally to innervate the thalamus and brainstem (Tripathi et al. in Brain Struct Funct 218:1133-1157, 2013). Here, we have reconstructed 16 previously undetected axons from the same tracer deposits that follow a more lateral trajectory. Virtually all 16 axons emanating from the different VP compartments collateralized in the extended amygdala system (EAS) and amygdaloid complex. The most frequent targets of axons from the lateral and medial (VPm) VP compartments were the rostral sublenticular extended amygdala, the extended amygdala (EA), the central nucleus of the amygdala and the posterior part of the basolateral amygdaloid nucleus. In contrast, axons from the rostral extension of the VP preferentially innervated the anterior amygdaloid area, the magnocellular preoptic nucleus, and the anterior part of the basomedial amygdaloid nucleus. We additionally found and reconstructed a single corticopetal axon arising from the VPm. The new results show that both direct and indirect projections from the basolateral complex and EAS to the ventral striatopallidal system are reciprocated by VP projections, and suggest that the systems can be activated simultaneously. The results additionally suggest that the amygdaloid complex and cortex are innervated separately from the VP. Finally, the combination of new and previous data indicate that approximately 84 % of VP axons (88/105) participate in basal ganglia circuits, 15 % (16/105) target the amygdaloid complex, and less than 1 % innervate the cortex.
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Affiliation(s)
- S Mongia
- Departamento de Anatomía, Facultad de Medicina, Universidad de Navarra, Ed. Los Castaños, C/. Irunlarrea 1, 31008, Pamplona, Navarra, Spain
| | - A Tripathi
- Center for Applied Medical Research (CIMA), Division of Neurosciences, Universidad de Navarra, Pamplona, Spain.,Department of Integrative Medical Biology, Umeå University, 90187, Umeå, Sweden
| | - E Mengual
- Center for Applied Medical Research (CIMA), Division of Neurosciences, Universidad de Navarra, Pamplona, Spain. .,Departamento de Anatomía, Facultad de Medicina, Universidad de Navarra, Ed. Los Castaños, C/. Irunlarrea 1, 31008, Pamplona, Navarra, Spain.
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Liu AKL, Chang RCC, Pearce RKB, Gentleman SM. Nucleus basalis of Meynert revisited: anatomy, history and differential involvement in Alzheimer's and Parkinson's disease. Acta Neuropathol 2015; 129:527-40. [PMID: 25633602 PMCID: PMC4366544 DOI: 10.1007/s00401-015-1392-5] [Citation(s) in RCA: 227] [Impact Index Per Article: 25.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2014] [Revised: 01/16/2015] [Accepted: 01/16/2015] [Indexed: 11/30/2022]
Abstract
It has been well established that neuronal loss within the cholinergic nucleus basalis of Meynert (nbM) correlates with cognitive decline in dementing disorders such as Alzheimer's disease (AD). Friedrich Lewy first observed his eponymous inclusion bodies in the nbM of postmortem brain tissue from patients with Parkinson's disease (PD) and cell loss in this area can be at least as extensive as that seen in AD. There has been confusion with regard to the terminology and exact localisation of the nbM within the human basal forebrain for decades due to the diffuse and broad structure of this "nucleus". Also, while topographical projections from the nbM have been mapped out in subhuman primates, no direct clinicopathological correlations between subregional nbM and cortical pathology and specific cognitive profile decline have been performed in human tissue. Here, we review the evolution of the term nbM and the importance of standardised nbM sampling for neuropathological studies. Extensive review of the literature suggests that there is a caudorostral pattern of neuronal loss within the nbM in AD brains. However, the findings in PD are less clear due to the limited number of studies performed. Given the differing neuropsychiatric and cognitive deficits in Lewy body-associated dementias (PD dementia and dementia with Lewy bodies) as compared to AD, we hypothesise that a different pattern of neuronal loss will be found in the nbM of Lewy body disease brains. Understanding the functional significance of the subregions of the nbM could prove important in elucidating the pathogenesis of dementia in PD.
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Affiliation(s)
- Alan King Lun Liu
- Neuropathology Unit, Division of Brain Sciences, Department of Medicine, Imperial College London, London, UK,
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Rolls ET, Deco G. Stochastic cortical neurodynamics underlying the memory and cognitive changes in aging. Neurobiol Learn Mem 2014; 118:150-61. [PMID: 25536108 DOI: 10.1016/j.nlm.2014.12.003] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2014] [Accepted: 12/06/2014] [Indexed: 12/17/2022]
Abstract
The relatively random spiking times of individual neurons provide a source of noise in the brain. We show how this noise interacting with altered depth in the basins of attraction of networks involved in short-term memory, attention, and episodic memory provide an approach to understanding some of the cognitive changes in normal aging. The effects of the neurobiological changes in aging that are considered include reduced synaptic modification and maintenance during learning produced in part through reduced acetylcholine in normal aging, reduced dopamine which reduces NMDA-receptor mediated effects, reduced noradrenaline which increases cAMP and thus shunts excitatory synaptic inputs, and the effects of a reduction in acetylcholine in increasing spike frequency adaptation. Using integrate-and-fire simulations of an attractor network implementing memory recall and short-term memory, it is shown that all these changes associated with aging reduce the firing rates of the excitatory neurons, which in turn reduce the depth of the basins of attraction, resulting in a much decreased probability in maintaining in short-term memory what has been recalled from the attractor network. This stochastic dynamics approach opens up new ways to understand and potentially treat the effects of normal aging on memory and cognitive functions.
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Affiliation(s)
- Edmund T Rolls
- Oxford Centre for Computational Neuroscience, Oxford, UK; University of Warwick, Department of Computer Science, Coventry CV4 7AL, UK.
| | - Gustavo Deco
- Universitat Pompeu Fabra, Theoretical and Computational Neuroscience, Roc Boronat 138, 08018 Barcelona, Spain; Institucio Catalana de Recerca i Estudis Avancats (ICREA), Spain
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Mesulam MM. Cholinergic circuitry of the human nucleus basalis and its fate in Alzheimer's disease. J Comp Neurol 2013; 521:4124-44. [PMID: 23852922 PMCID: PMC4175400 DOI: 10.1002/cne.23415] [Citation(s) in RCA: 227] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2013] [Revised: 05/11/2013] [Accepted: 06/28/2013] [Indexed: 01/15/2023]
Abstract
The nucleus basalis is located at the confluence of the limbic and reticular activating systems. It receives dopaminergic input from the ventral tegmental area/substantia nigra, serotonergic input from the raphe nuclei, and noradrenergic input from the nucleus locus coeruleus. Its cholinergic contingent, known as Ch4, provides the principal source of acetylcholine for the cerebral cortex and amygdala. More than half of presynaptic varicosities along its cholinergic axons make traditional synaptic contacts with cortical neurons. Limbic and paralimbic cortices of the brain receive the heaviest cholinergic input from Ch4 and are also the principal sources of reciprocal cortical projections back to the nucleus basalis. This limbic affiliation explains the role of the nucleus basalis in modulating the impact and memorability of incoming sensory information. The anatomical continuity of the nucleus basalis with other basomedial limbic structures may underlie its early and high vulnerability to the tauopathy and neurofibrillary degeneration of Alzheimer's disease. The tauopathy in Ch4 eventually leads to the degeneration of the cholinergic axons that it sends to the cerebral cortex. The early involvement of Ch4 has a magnifying effect on Alzheimer's pathology, because neurofibrillary degeneration in a small number of neurons can perturb neurotransmission in all cortical areas. Although the exact contribution of the Ch4 lesion to the cognitive changes of Alzheimer's disease remains poorly understood, the cholinergic circuitry of the nucleus basalis is emerging as one of the most strategically positioned and behaviorally consequential modulatory systems of the human cerebral cortex. J. Comp. Neurol. 521:4124-4144, 2013. © 2013 Wiley Periodicals, Inc.
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Affiliation(s)
- M.-Marsel Mesulam
- Cognitive Neurology and Alzheimer's Disease Center, Northwestern University Medical School, Chicago, Illinois 60611
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Gratwicke J, Kahan J, Zrinzo L, Hariz M, Limousin P, Foltynie T, Jahanshahi M. The nucleus basalis of Meynert: A new target for deep brain stimulation in dementia? Neurosci Biobehav Rev 2013; 37:2676-88. [DOI: 10.1016/j.neubiorev.2013.09.003] [Citation(s) in RCA: 82] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2013] [Revised: 08/30/2013] [Accepted: 09/02/2013] [Indexed: 10/26/2022]
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Hardy H, Heimer L, Switzer R, Watkins D. Simultaneous demonstration of horseradish peroxidase and acetylcholinesterase. Neurosci Lett 2012; 3:1-5. [PMID: 19604859 DOI: 10.1016/0304-3940(76)90090-2] [Citation(s) in RCA: 140] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/1976] [Accepted: 07/06/1976] [Indexed: 11/15/2022]
Abstract
Simultaneous demonstration of acetylcholinesterase (AChE) and horseradish peroxidase (HRP) has been achieved by staining frozen sections with a modified Koelle-Friedenwald thiocholine method for AChE followed directly by the Graham-Karnovsky procedure for HRP. By using sodium sulfite instead of sodium sulfide in the AChE procedure, the final reaction product appears as black AChE granules that contrast sharply with the yellowish-brown HRP granules.
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Affiliation(s)
- H Hardy
- Department of Anatomy, University of Virginia, Charlottesville, Va. U.S.A
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Raghanti M, Simic G, Watson S, Stimpson C, Hof P, Sherwood C. Comparative analysis of the nucleus basalis of Meynert among primates. Neuroscience 2011; 184:1-15. [DOI: 10.1016/j.neuroscience.2011.04.008] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2011] [Revised: 04/05/2011] [Accepted: 04/06/2011] [Indexed: 11/28/2022]
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Hermanstyne TO, Kihira Y, Misono K, Deitchler A, Yanagawa Y, Misonou H. Immunolocalization of the voltage-gated potassium channel Kv2.2 in GABAergic neurons in the basal forebrain of rats and mice. J Comp Neurol 2011; 518:4298-310. [PMID: 20853508 DOI: 10.1002/cne.22457] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The Kv2 voltage-gated potassium channels, Kv2.1 and Kv2.2, are important regulators of neuronal excitability in mammalian brain. It has been shown that Kv2.1 channels are expressed in virtually all neurons in the brain. However, the cellular localization of Kv2.2 has not been fully elucidated. In this article we report that Kv2.2 is highly expressed in a subset of neurons in the magnocellular preoptic nucleus (MCPO) and the horizontal limb of the diagonal band of Broca (HDB) of the basal forebrain complex, which are areas highly implicated in the regulation of cortical activity and the sleep/wake cycle. It has been shown that MCPO and HDB contain distinct populations of neurons that differ in their neurochemicals, cholinergic, glutamatergic, and gamma-aminobutyric acid (GABA)ergic neurons. Using specific immunolabeling and knockin mice in which green fluorescent protein (GFP) is expressed in GABAergic neurons, we found that Kv2.2 is abundantly expressed in a large subpopulation of the GABAergic neurons in the MCPO and HDB. These data offer Kv2.2 as a molecular target to study the role of the specific subpopulation of basal forebrain GABAergic neurons.
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Affiliation(s)
- Tracey O Hermanstyne
- Department of Neural and Pain Sciences, University of Maryland, Baltimore, Maryland 21201, USA
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16
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Jones EG. Organization of the Thalamocortical Complex and its Relation to Sensory Processes. Compr Physiol 2011. [DOI: 10.1002/cphy.cp010305] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Saper CB. Diffuse Cortical Projection Systems: Anatomical Organization and Role in Cortical Function. Compr Physiol 2011. [DOI: 10.1002/cphy.cp010506] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Abstract
AbstractAs neurophysiological investigations of sleep cycle control have provided an increasingly detailed picture of events at the cellular level, the concept that the sleep cycle is generated by the interaction of multiple, anatomically distributed sets of neurons has gradually replaced the hypothesis that sleep is generated by a single, highly localized neuronal oscillator.Cell groups that discharge during rapid-eye-movement (REM) sleep (REM-on) and neurons that slow or cease firing during REM sleep (REM-off) have long been thought to comprise at least two neurochemically distinct populations. The fact that putatively cholinoceptive and/or cholinergic (REM-on) and putatively aminergic (REM-off) cell populations discharge reciprocally over the sleep cycle suggests a causal interdependence.In some brain stem areas these cell groups are not anatomically segregated and may instead be neurochemically mixed (interpenetrated). This finding raises important theoretical and practical issues not anticipated in the original reciprocal-interaction model. The electrophysiological evidence concerning the REM-on and REM-off cell groups suggests a gradient of sleep-dependent membrane excitability changes that may be a function of the connectivity strength within an anatomically distributed neuronal network. The connectivity strength may be influenced by the degree of neurochemical interpenetration between the REM-on and REM-offcells. Recognition of these complexities forces us to revise the reciprocal-interaction model and to seek new methods to test its tenets.Cholinergic microinjection experiments indicate that some populations of REM-on cells can execute specific portions of the REM sleep syndrome or block the generation of REM sleep. This observation suggests that the order of activation within the anatomically distributed generator populations may be critical in determining behavioral outcome. Support for the cholinergic tenets of the reciprocal-interaction model has been reinforced by observations from sleep-disorders medicine.Specific predictions of the reciprocal-interaction model and suggestions for testing these predictions are enumerated for future experimental programs that aim to understand the cellular and molecular basis of the mammalian sleep cycle.
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Arqué G, de Lagrán MM, Arbonés ML, Dierssen M. Age-associated motor and visuo-spatial learning phenotype in Dyrk1A heterozygous mutant mice. Neurobiol Dis 2009; 36:312-9. [PMID: 19660545 DOI: 10.1016/j.nbd.2009.07.027] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2009] [Revised: 07/27/2009] [Accepted: 07/28/2009] [Indexed: 01/08/2023] Open
Abstract
Dual-specificity tyrosine-regulated kinase 1A (DYRK1A) is a candidate gene for the Down syndrome neurological defects and may be involved in the progression of Alzheimer's disease. Heterozygous mice for Dyrk1A (Dyrk1A+/-) exhibit decreased brain size, motor abnormalities and cognitive deficits in the adult. However, there is no information about the mutant phenotype in old ages. Here we analyze the impact of Dyrk1A dosage reduction on motor performance and hippocampal-dependent learning and memory in aged Dyrk1A+/- mice. Whereas motor tests showed marked alterations in traction ability, prehensile reflex and balance, heterozygous mice only present a slight impairment of visuo-spatial memory even though they show a robust decrease of CA1-CA3 and dentate gyrus cells.
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Affiliation(s)
- Glòria Arqué
- Genes and Disease Program, Center for Genomic Regulation (CRG), Pompeu Fabra University, Barcelona Biomedical Research Park (PRBB) and CIBER de Enfermedades Raras (CIBERER), Barcelona, Spain
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Wirths O, Breyhan H, Schäfer S, Roth C, Bayer TA. Deficits in working memory and motor performance in the APP/PS1ki mouse model for Alzheimer's disease. Neurobiol Aging 2008; 29:891-901. [PMID: 17215062 DOI: 10.1016/j.neurobiolaging.2006.12.004] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2006] [Revised: 11/23/2006] [Accepted: 12/11/2006] [Indexed: 10/23/2022]
Abstract
The APP/PS1ki mouse model for Alzheimer's disease (AD) exhibits robust brain and spinal cord axonal degeneration and hippocampal CA1 neuron loss starting at 6 months of age. It expresses human mutant APP751 with the Swedish and London mutations together with two FAD-linked knocked-in mutations (PS1 M233T and PS1 L235P) in the murine PS1 gene. The present report covers a phenotypical analysis of this model using either behavioral tests for working memory and motor performance, as well as an analysis of weight development and body shape. At the age of 6 months, a dramatic, age-dependent change in all of these properties and characteristics was observed, accompanied by a significantly reduced ability to perform working memory and motor tasks. The APP/PS1ki mice were smaller and showed development of a thoracolumbar kyphosis, together with an incremental loss of body weight. While 2-month-old APP/PS1ki mice were inconspicuous in all of these tasks and properties, there is a massive age-related impairment in all tested behavioral paradigms. We have previously reported robust axonal degeneration in brain and spinal cord, as well as abundant hippocampal CA1 neuron loss starting at 6 months of age in the APP/PS1ki mouse model, which coincides with the onset of motor and memory deficits described in the present report.
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Affiliation(s)
- Oliver Wirths
- Department of Psychiatry, University of Goettingen, von-Siebold-Str. 5, D-37075 Goettingen, Germany.
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Rüdiger T, Bolz J. Acetylcholine influences growth cone motility and morphology of developing thalamic axons. Cell Adh Migr 2008; 2:30-7. [PMID: 19262162 DOI: 10.4161/cam.2.1.5909] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
The neurotransmitter acetylcholine (ACh) is expressed in the developing telencephalon at the time when thalamic axons project to the cortex, long before synapses are being formed. Since previous studies demonstrated an influence of ACh on neurite extension we used different in vitro assays to examine possible effects of ACh on the growth of thalamic axons. In explant cultures, application of ACh reduced the length of thalamic axons in a dose dependent manner, an effect that could also be evoked by selective muscarinic and nicotinic agonists. Time-lapse imaging of thalamic axons exposed to microscopic gradients of ACh revealed that growth cones no longer advanced, but maintained high filopodial activity. This growth cone pausing was not accompanied by axon retraction or growth cone collapse. It could at least partially be blocked by muscarinic and nicotinic antagonists, indicating that both types of ACh receptors contribute to mediate these effects on thalamic axons. Finally, we also found that ACh changed the morphology of growth cones; they became larger and extended more filopodia. Since such changes in the structure and motility of growth cones are observed at decision regions along the path of many fiber populations including thalamic axons, we suggest that ACh plays a role during the elaboration of thalamocortical projections.
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Affiliation(s)
- Tina Rüdiger
- Universität Jena, Institut für Allgemeine Zoologie und Tierphysiologie, Jena, Germany
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Boban M, Kostovic I, Simic G. Nucleus subputaminalis: neglected part of the basal nucleus of Meynert. Brain 2006; 129:E42; author reply E43. [PMID: 16543395 DOI: 10.1093/brain/awl025] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Neurogenesis of the magnocellular basal telencephalic nuclei in the rat. Int J Dev Neurosci 2003; 3:229-43. [DOI: 10.1016/0736-5748(85)90028-0] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/13/1984] [Indexed: 11/21/2022] Open
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Weller RE, Steele GE, Kaas JH. Pulvinar and other subcortical connections of dorsolateral visual cortex in monkeys. J Comp Neurol 2002; 450:215-40. [PMID: 12209852 DOI: 10.1002/cne.10298] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The present study used injections of neuroanatomical tracers to determine the subcortical connections of the caudal and rostral subdivisions of the dorsolateral area (DL) and the middle temporal crescent area (MT(C)) in owl monkeys (Aotus trivirgatus), squirrel monkeys (Saimiri sciureus), and macaque monkeys (Macaca fascicularis and M. radiata). Emphasis was on connections with the pulvinar. Patterns of corticopulvinar connections were related to subdivisions of the inferior pulvinar (PI) defined by histochemical or immunocytochemical architecture. Connections of DL/MT(C) were with the PI subdivisions, PICM, PICL, and PIp; the lateral pulvinar (PL); and, more sparsely, the lateral portion of the medial pulvinar (PM). In squirrel monkeys, there was a tendency for caudal DL to have stronger connections with PICL than PICM and for rostral DL/MT(C) to have stronger connections with PICM than PICL. In all three primates, DL/MT(C) had reciprocal connections with the pulvinar and claustrum; received afferents from the locus coeruleus, dorsal raphe, nucleus annularis, central superior nucleus, pontine reticular formation, lateral geniculate nucleus, paracentral nucleus, central medial nucleus, lateral hypothalamus, basal nucleus of the amygdala, and basal nucleus of Meynert/substantia innominata; and sent efferents to the pons, superior colliculus, reticular nucleus, caudate, and putamen. Projections from DL/MT(C) to the nucleus of the optic tract were also observed in squirrel and owl monkeys. Similarities in the subcortical connections of the dorsolateral region, especially those with the pulvinar, provide further support for the conclusion that the DL regions are homologous in the three primate groups.
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Affiliation(s)
- Rosalyn E Weller
- Department of Psychology, University of Alabama at Birmingham, Birmingham, Alabama 35294, USA.
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Doi A, Ishibashi H, Jinno S, Kosaka T, Akaike N. Presynaptic inhibition of GABAergic miniature currents by metabotropic glutamate receptor in the rat CNS. Neuroscience 2002; 109:299-311. [PMID: 11801366 DOI: 10.1016/s0306-4522(01)00484-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The modulation of spontaneous miniature GABAergic inhibitory postsynaptic currents (mIPSC) by the metabotropic glutamate receptors was investigated in the mechanically dissociated rat nucleus basalis of Meynert neurons using the conventional whole-cell patch recording configuration. An application of (+/-)-1-aminocyclopentane-trans-1,3-dicarboxylic acid (tACPD) reversibly reduced the frequency of mIPSC without affecting the current amplitude distribution. The application of K+ channel blockers such as 4-aminopyridine, Cs+, Ba2+ or tetraethylammonium increased the mIPSC frequency, but failed to inhibit the tACPD action on mIPSC. Although the removal of Ca2+ from the extracellular solution reduced the mIPSC frequency, the inhibitory effect of tACPD on mIPSC was unaltered. These results suggested that neither voltage-dependent K+ or Ca2+ channels are involved in the inhibitory effect of tACPD on mIPSC frequency. Forskolin, an activator of adenylate cyclase, facilitated the mIPSC frequency in a concentration-dependent manner and inhibited the tACPD-induced suppression of mIPSC frequency. 8-Br-cAMP, a membrane permeable analog of cAMP, also prevented the inhibitory action of tACPD. However, Sp-cAMP, an activator of protein kinase A, could not prevent the inhibitory action of tACPD. L-CCG-I and (2R,4R)-APDC, group II mGluR agonists, mimicked the tACPD action on mIPSC frequency, but L-AP4, a group III mGluR agonist, had no such effect. MCCG, a group II mGluR antagonist, fully blocked the tACPD action. It was concluded that the activation of group II mGluR on the GABAergic presynaptic nerve terminals projecting to the rat nucleus basalis of Meynert neurons therefore inhibits the GABA release by reducing the activity of the cAMP-dependent pathway.
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Affiliation(s)
- A Doi
- Cellular and System Physiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan
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Baratta J, Ha DH, Yu J, Robertson RT. Evidence for target preferences by cholinergic axons originating from different subdivisions of the basal forebrain. BRAIN RESEARCH. DEVELOPMENTAL BRAIN RESEARCH 2001; 132:15-21. [PMID: 11744103 DOI: 10.1016/s0165-3806(01)00290-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Possible target preferences of basal forebrain cholinergic neurons were studied in organotypic slice cultures. Cholinergic neurons in slices of medial septum or substantia innominata send axons into both hippocampus and neocortex when co-cultured together. However, septal cholinergic axons course through adjacent slices of neocortex to reach and branch densely in slices of hippocampus, but septal axons seldom grow beyond adjacent hippocampal tissue to reach neocortex. In contrast, cholinergic axons from substantia innominata commonly grow through hippocampus to reach neocortex, and also grow through neocortex to reach hippocampus, with similar branching densities in each target. The greater density of septal axonal branches in hippocampus than in neocortex suggests a preference of septal axons for the hippocampal target.
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Affiliation(s)
- J Baratta
- Department of Anatomy and Neurobiology, College of Medicine, University of California-Irvine, Irvine, CA 92697-1280, USA
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Villalobos J, Rios O, Barbosa M. Postnatal development of cholinergic system in mouse basal forebrain: acetylcholinesterase histochemistry and choline-acetyltransferase immunoreactivity. Int J Dev Neurosci 2001; 19:495-502. [PMID: 11470379 DOI: 10.1016/s0736-5748(01)00034-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
The distribution of acetylcholinesterase histochemistry and choline-O-acetyltransferase immunohistochemistry in the basal forebrain was studied in newborn mice (P0) and until 60 days of postnatal life (P60). A weak acetylcholinesterase activity was found at P0 and P2 in the anterior and intermediate parts of the basal forebrain, and higher in the posterior region. The intensity of labeling, neuronal size and dendritic growth seems to increase progressively in all regions of basal forebrain from P4 to P10. The AChE+ cell count shows that in the anterior portion of the magnocellular basal nucleus the number of cells does not vary significantly from birth to the second month of postnatal life. However, in the intermediate and posterior portions of the nucleus the mean number of labeled cells increases significantly from birth to the end of the second week of postnatal life (P13). The choline-acetyltransferase immunoreactivity appears only detectable at the end of the first week (P6) as a slight immunoreaction, which increases progressively in intensity at P8, and at P10 seems to attain the same intensity of labeling found at P60. These results seem to indicate that the acetylcholinesterase could have a non-classic cholinergic role in the first stages of postnatal development, acting as a growth and cellular differentiation factor.
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Affiliation(s)
- J Villalobos
- Centro de Neurociencias, Facultad de Salud, Universidad del Valle, Apartado Aéreo 25360, Cali, Colombia.
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Semba K. Multiple output pathways of the basal forebrain: organization, chemical heterogeneity, and roles in vigilance. Behav Brain Res 2000; 115:117-41. [PMID: 11000416 DOI: 10.1016/s0166-4328(00)00254-0] [Citation(s) in RCA: 183] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Studies over the last decade have shown that the basal forebrain (BF) consists of more than its cholinergic neurons. The BF also contains non-cholinergic neurons, including gamma-aminobutyric acid-ergic neurons which co-distribute and co-project with the cholinergic neurons. Both types of neuron project, in variable proportions, to the cerebral cortex, hippocampus, thalamus, amygdala, and olfactory bulb, whereas descending projections to the posterior hypothalamus and brainstem nuclei are predominantly non-cholinergic. Some of the cholinergic and non-cholinergic projection neurons contain neuropeptides such as galanin, nitric oxide synthase, and possibly glutamate. To understand better the function of the BF, the organization of the multiple ascending and descending projections of BF neurons is reviewed along with their neurochemical heterogeneity, and possible functions of individual pathways are discussed. It is proposed that BF neurons belong to multiple systems with distinct cognitive, motivational, emotional, motor, and regulatory functions, and that through these pathways, the BF plays a role in controlling both cognitive and non-cognitive aspects of vigilance.
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Affiliation(s)
- K Semba
- Department of Anatomy and Neurobiology, Dalhousie University, B3H 4H7, Halifax, NS, Canada.
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Kanda T, Iwasaki T, Nakamura S, Kurokawa T, Ikeda K, Mizusawa H. Self-secretion of fibroblast growth factor-9 supports basal forebrain cholinergic neurons in an autocrine/paracrine manner. Brain Res 2000; 876:22-30. [PMID: 10973589 DOI: 10.1016/s0006-8993(00)02563-4] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
We examined the effect of fibroblast growth factor (FGF)-9 on primary cultures of rat basal forebrain cholinergic neurons (BFCN) obtained at embryonic day 17. FGF-9 enhanced survival of AChE-positive neurons, increased their mean soma size, and up-regulated their choline acetyltransferase (ChAT) activity. The ChAT-promoting effect of FGF-9 was approximately as potent as that of nerve growth factor (NGF) and was greater than those of basic fibroblast growth factor (bFGF), ciliary neurotrophic factor (CNTF), or glia-derived neurotrophic factor (GDNF). Simultaneous addition of FGF-9 and NGF induced extremely high ChAT levels, suggesting that FGF-9 and NGF may enhance cholinergic properties in BFCN via different pathways that can act synergistically. In immunocytochemical and in situ hybridization studies in cultured cells and also in sections of adult rat brain, BFCN showed cytoplasmic immunostaining for FGF-9 and expressed FGF-9 messenger RNA; thus, we concluded that FGF-9 acts on BFCN in an autocrine and/or paracrine manner. Although effective delivery of exogenous FGF-9 into the central nervous system remains a problem to be solved, FGF-9 may be a promising candidate for therapeutic trials in Alzheimer disease.
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Affiliation(s)
- T Kanda
- Department of Neurology, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo, 113-8519, Tokyo, Japan.
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Künzle H, Radtke-Schuller S. Basal telencephalic regions connected with the olfactory bulb in a Madagascan hedgehog tenrec. J Comp Neurol 2000; 423:706-26. [PMID: 10880998 DOI: 10.1002/1096-9861(20000807)423:4<706::aid-cne13>3.0.co;2-#] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
In an attempt to gain insight into the organization and evolution of the basal forebrain, the region was analysed cytoarchitecturally, chemoarchitecturally, and hodologically in a lower placental mammal, the lesser hedgehog tenrec. Particular emphasis was laid on the subdivision of the olfactory tubercle, the nuclear complex of the diagonal band, and the cortical amygdala. The proper tubercule and the rostrolateral tubercular seam differed from each other with regard to their immunoreactivity to calbindin and calretinin, as well as their afferents from the piriform cortex. Interestingly, the tubercular seam showed similar properties to the dwarf cell compartment, located immediately adjacent to the islands of Calleja. The most prominent input to the olfactory bulb (OfB) originated from the diagonal nuclear complex. This projection was ipsilateral, whereas the bulbar afferents from the hypothalamus and the mesopontine tegmentum were bilateral. The amygdala projected only sparsely to the OfB, but received a prominent bulbar projection. An exception was the nucleus of the lateral olfactory tract, which was poorly connected with the OfB. Unlike other species with an accessory OfB, the projections from the tenrec's main OfB did not show a topographic organization upon the lateral and medial olfactory amygdala. However, there was an accessory amygdala, which could be differentiated from the lateral nuclei by its intense reaction to NADPh-diaphorase. This reaction was poor in the diagonal nuclear complex as in monkey but unlike in rat. The variability of cell populations and olfactory bulb connections shown here may help to clarify both phylogenetic relationships and the significance of individual basal telencephalic subdivisions.
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Affiliation(s)
- H Künzle
- Institute of Anatomy, University of Munich, D-80336 Munich, Germany
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Chaillan FA, Truchet B, Roman FS, Soumireu-Mourat B. Early polysynaptic potentiation recorded in the dentate gyrus during an associative learning task. Neuroscience 1999; 94:443-51. [PMID: 10579207 DOI: 10.1016/s0306-4522(99)00304-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In this report, we investigated the electrophysiological dynamics of the neuronal circuit including the dentate gyrus during an associative task. A group of rats was trained to discriminate between a patterned electrical stimulation of the lateral olfactory tract, used as an artificial cue associated with a water reward, and a natural odor associated with a light flash. Polysynaptic field potential responses, evoked by a single electrical stimulation of the same lateral olfactory tract electrode, were recorded in the molecular layer of the ipsilateral dentate gyrus prior to and just after each training session. An increase in this response was observed when a significant discrimination of the two cues began. A positive correlation was found between the change in the polysynaptic potentiation and behavioral performances. The onset latency of the potentiated polysynaptic response was 35-45 ms. When a group of naive animals was pseudoconditioned, no change in field potential was observed. These results are consistent with the hypothesized dynamic activation of the dentate gyrus early in the making of association, allowing gradual storage of associative information in a defined set of synapses. Moreover, the onset latency of the potentiated response suggests the existence of reactivating hippocampal loops during the processing of associative information.
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Affiliation(s)
- F A Chaillan
- Laboratoire de Neurobiologie des Comportements, UMR 6562, Université de Provence, I.B.H.O.P., Traverse Charles Susini, Marseille, France.
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Simić G, Mrzljak L, Fucić A, Winblad B, Lovrić H, Kostović I. Nucleus subputaminalis (Ayala): the still disregarded magnocellular component of the basal forebrain may be human specific and connected with the cortical speech area. Neuroscience 1999; 89:73-89. [PMID: 10051218 DOI: 10.1016/s0306-4522(98)00304-2] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The small magnocellular group located within the rostrolateral extension of the basal forebrain was named and described as the nucleus subputaminalis in the human and chimpanzee brain by Ayala. Analysis of cytoarchitectonic and cytochemical characteristics of this cell group has been largely disregarded in both classical and more current studies. We examined the nucleus subputaminalis in 33 neurologically normal subjects (ranging from 15 weeks of gestation to 71 years-of-age) by using Nissl staining, choline acetyltransferase immunohistochemistry, acetyl cholinesterase histochemistry and nerve growth factor receptor immunocytochemistry. In addition, we applied reduced nicotinamide adenine dinucleotide phosphate-diaphorase histochemistry and calbindin-D28k immunocytochemistry in three neurologically normal subjects. At the most rostrolateral levels we describe the previously poorly characterized component of the lateral (periputaminal) subdivision of the subputaminal nucleus, which may be human specific since it is not described in non-human primates. Moreover, we find the human subputaminal nucleus best developed at the anterointermediate level, which is the part of the basal nucleus that is usually much smaller or missing in monkeys. The location of subputaminal cholinergic neurons within the frontal lobe, the ascension of their fibers through the external capsule towards the inferior frontal gyrus, the larger size of the subputaminal nucleus on the left side at the most rostral and anterointermediate levels and the most protracted development among all magnocellular aggregations within the basal forebrain strongly suggest that they may be connected with the cortical speech area. These findings give rise to many hypotheses about the possible role of the subputaminal nucleus in various neurodegenerative, neurological and psychiatric disorders, particularly Alzheimer's disease and primary progressive aphasia. Therefore, future studies on the basal forebrain should more carefully investigate this part of the basal nucleus.
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Affiliation(s)
- G Simić
- Croatian Institute for Brain Research and Department of Anatomy, Zagreb University School of Medicine, Croatia
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Donzelli R, Marinkovic S, Brigante L, de Divitiis O, Nikodijevic I, Schonauer C, Maiuri F. Territories of the perforating (lenticulostriate) branches of the middle cerebral artery. Surg Radiol Anat 1999; 20:393-8. [PMID: 9932322 DOI: 10.1007/bf01653128] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The territories of the central branches of the middle cerebral artery (MCA) were examined in 21 injected human brains. It was noted that these central arteries supplied: the caudate nucleus (dorsolateral half of the rostral part of its head; the entire caudal part of the head; the body and rostral portion of the tail in some cases), the putamen (dorsolateral part of its rostral portion, the remainder of the putamen, except the most caudal part occasionally), the globus pallidus (the entire lateral segment, except the ventrorostral and, sometimes, the most caudal part), the basal forebrain (lateral parts of the basal nucleus of Meynert and the nucleus of the diagonal band, as well as fiber bundles in this region), the internal capsule (dorsal and ventrocaudal part of the anterior limb, dorsal part of the genu, dorsal and ventrorostral part of the posterior limb), the corona radiata (a narrow strip close to the internal capsule) and the cerebral cortex (the caudal orbitofrontal cortex occasionally). The presented data may have certain neuroradiologic, neurologic and neurosurgical significance.
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Affiliation(s)
- R Donzelli
- Institute of Neurosurgery, School of Medicine, University of Naples Federico II, Napoli, Italy
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Heimer L, de Olmos J, Alheid G, Pearson J, Sakamoto N, Shinoda K, Marksteiner J, Switzer R. The human basal forebrain. Part II. HANDBOOK OF CHEMICAL NEUROANATOMY 1999. [DOI: 10.1016/s0924-8196(99)80024-4] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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Durand M, Coronas V, Jourdan F, Quirion R. Developmental and aging aspects of the cholinergic innervation of the olfactory bulb. Int J Dev Neurosci 1998; 16:777-85. [PMID: 10198824 DOI: 10.1016/s0736-5748(98)00087-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
Abstract
The olfactory bulb is a limbic paleocortex which receives monosynaptic sensory afferents from the olfactory mucosa, and a strong direct cholinergic input from the basal forebrain. This review focuses on the rat olfactory bulb as a suitable model to study cholinergic involvements in cortical processing, during development, adulthood and aging. Anatomical and biochemical data show that cholinergic influences upon the bulbar neuronal network are exerted through several types of target cells and receptors (muscarinic and nicotinic). Functional data indicate that cholinergic afferents to the olfactory bulb are involved in local events related to olfactory learning. Neurodegenerative disorders such as Alzheimer's disease involve early olfactory deficits and typical histopathological lesions in the olfactory bulb. In summary, with its exclusively extrinsic cholinergic innervation and direct sensory input, the rat olfactory bulb offers the opportunity to study the cellular and molecular mechanisms of cholinergic influences on cortical processing, in both normal and pathological conditions.
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Affiliation(s)
- M Durand
- Douglas Hospital Research Centre, Department of Psychiatry, McGill University, Montreal, Québec, Canada
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Asahina M, Suhara T, Shinotoh H, Inoue O, Suzuki K, Hattori T. Brain muscarinic receptors in progressive supranuclear palsy and Parkinson's disease: a positron emission tomographic study. J Neurol Neurosurg Psychiatry 1998; 65:155-63. [PMID: 9703164 PMCID: PMC2170218 DOI: 10.1136/jnnp.65.2.155] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
OBJECTIVES To assess muscarinic acetylcholine receptors (mAChRs) in the brains of patients with progressive supranuclear palsy and Parkinson's disease, and to correlate the cholinergic system with cognitive function in progressive supranuclear palsy and Parkinson's disease. METHODS Positron emission tomography (PET) and [11C]N-methyl-4-piperidyl benzilate ([11C]NMPB) was used to measure mAChRs in the brain of seven patients with progressive supranuclear palsy, 12 patients with Parkinson's disease, and eight healthy controls. All of the patients with progressive supranuclear palsy were demented. The Parkinson's disease group consisted of 11 non-demented patients and one demented patient. The mini mental state examination (MMSE) was used to assess the severity of cognitive dysfunction in all of the subjects. The modified Wisconsin card sorting test (WCST) was used to evaluate frontal cognitive function in the non-demented patients with Parkinson's disease and controls. RESULTS The mean K3 value, an index of mAChR binding, was significantly higher for the frontal cortex in the patients with Parkinson's disease than in the controls (p<0.01). By contrast, the patients with progressive supranuclear palsy had no significant changes in the K3 values of any cerebral cortical regions. The mean score of the MMSE in the progressive supranuclear palsy group was significantly lower than that in the control group. Although there was no difference between the Parkinson's disease and control groups in the MMSE, the non-demented patients with Parkinson's disease showed significant frontal lobe dysfunction in the WCST. CONCLUSIONS The increased mAChR binding in the frontal cortex of the patients with Parkinson's disease may reflect denervation hypersensitivity caused by loss of the ascending cholinergic input to that region from the basal forebrain and may be related to frontal lobe dysfunction in Parkinson's disease. The cerebral cortical cholinergic system may not have a major role in cognitive dysfunction in progressive supranuclear palsy.
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Affiliation(s)
- M Asahina
- Division of Clinical Research and Radiation Health, National Institute of Radiological Science, Chiba, Japan.
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Gritti I, Mariotti M, Mancia M. GABAergic and cholinergic basal forebrain and preoptic-anterior hypothalamic projections to the mediodorsal nucleus of the thalamus in the cat. Neuroscience 1998; 85:149-78. [PMID: 9607710 DOI: 10.1016/s0306-4522(97)00573-3] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The present study examined projections of GABAergic and cholinergic neurons from the basal forebrain and preoptic-anterior hypothalamus to the "intermediate" part of the mediodorsal nucleus of the thalamus. Retrograde transport from this region of the mediodorsal nucleus was investigated using horseradish peroxidase-conjugated wheatgerm agglutinin in combination with peroxidase-antiperoxidase immunohistochemical staining for glutamic acid decarboxylase and choline acetyltransferase. A relatively large number of retrogradely-labelled glutamic acid decarboxylase-positive neurons are located in the basal forebrain, amounting to more than 7% of the total population of glutamic acid decarboxylase-positive cells in this region. Moreover, retrogradely-labelled choline acetyltransferase-positive cells are interspersed among glutamic acid decarboxylase-positive neurons, accounting for about 6% of the total choline acetyltransferase-positive cell population in the basal forebrain. The glutamic acid decarboxylase-positive and choline acetyltransferase-positive retrogradely-labelled neurons are distributed throughout several regions of the basal forebrain, including the medial septum, the diagonal band of Broca, the magnocellular preoptic nucleus, the substantia innominata pars anterior, the substantia innominata pars posterior, and the globus pallidus where only a few retrogradely-labelled neurons were seen. The choline acetyltransferase-positive mediodorsal-projecting neurons are morphologically different from the choline acetyltransferase-positive neurons in the basal forebrain, suggesting that those projecting to the mediodorsal nucleus are a small proportion of the cholinergic neuronal population in the basal forebrain. In the preoptic-anterior hypothalamus, many retrogradely-labelled glutamic acid decarboxylase-positive cells were found, amounting to more than 7% of the total population of glutamic acid decarboxylase-positive cells in this region. These retrogradely-labelled glutamic acid decarboxylase-positive neurons are distributed throughout the preoptic-anterior hypothalamus in a continuous line with those in the basal forebrain, including the lateral preoptic area, the medial preoptic area, the bed nucleus of the stria terminalis, and the anterior and dorsal hypothalamic areas. The highest percentage of mediodorsal-projecting GABAergic neurons is in the anterior lateral hypothalamus where more than 25% of the total population of glutamic acid decarboxylase-positive cells project to the mediodorsal nucleus of the thalamus. Overall, of the large population of retrogradely-labelled neurons in the basal forebrain and preoptic-anterior hypothalamus, a significant proportion are glutamic acid decarboxylase-positive neurons (> 60% in the basal forebrain and > 30% in the preoptic-anterior hypothalamus), while the choline acetyltransferase-positive neurons amount to a smaller percentage of the neurons projecting to the mediodorsal nucleus (< 13% in the basal forebrain and < 2% in the preoptic-anterior hypothalamus). These results provide anatomical evidence of direct GABAergic projections from the basal forebrain and preoptic-anterior hypothalamic regions to the "intermediate" part of the mediodorsal nucleus in the cat. This GABAergic projection field could be the direct pathway by which the basal forebrain directly modulates thalamic excitability and may also be involved in mechanisms modulating electroencephalographic synchronization and sleep through the "intermediate" mediodorsal nucleus.
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Affiliation(s)
- I Gritti
- Institute of Human Physiology II, University of Milano, Italy
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Distinctive morphological features of a subset of cortical neurons grown in the presence of basal forebrain neurons in vitro. J Neurosci 1998. [PMID: 9592099 DOI: 10.1523/jneurosci.18-11-04201.1998] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Basal forebrain cholinergic neurons (BFCNs) provide the major subcortical source of cholinergic input to cerebral cortex and play an important role in regulating cortical activity. The present study examined the ability of BFCNs to influence neocortical neuronal growth by examining effects of the presence of BFCNs on certain cortical neurons grown under the controlled conditions of dissociated cell culture. Initial experiments demonstrated distinctive morphological features of a population of neurons (labeled with SMI-32, a monoclonal antibody to nonphosphorylated neurofilament proteins that labels pyramidal neurons in vivo) in cocultures containing basal forebrain (BF) and cortical cells. These neurons (large neurons immunoreactive for SMI-32 [SMI-32(+) neurons]) were characterized as having extensive axons, greater soma size, and more dendritic growth than did most SMI-32(+) neurons in the cultures. Staining for SMI-32 in cocultures in which the cortical neurons were labeled with a fluorescent marker before adding the BF cells indicated that virtually all large SMI-32(+) neurons were of cortical origin. Eliminating BFCNs with the selective cholinergic immunotoxin 192 IgG-saporin resulted in a >80% decrease in the number of large SMI-32(+) neurons, although causing little damage to other cells in the treated cultures; this suggests that survival or maintenance of large SMI-32(+) neurons may depend on ongoing trophic support from BFCNs. Thus, present findings suggest that BFCNs may provide powerful growth- and/or survival-enhancing signals to a subset of cortical neurons.
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Rhee JS, Jin YH, Akaike N. Developmental changes of GABA(A) receptor-chloride channels in rat Meynert neurons. Brain Res 1998; 779:9-16. [PMID: 9473565 DOI: 10.1016/s0006-8993(97)01064-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The developmental changes of GABA(A) receptors were investigated in Meynert neurons freshly dissociated from day 0, 2 week-, and 6 month-old rats using both nystatin and gramicidin perforated patch recording modes under voltage-clamp conditions. The age-related changes in the current amplitude and threshold concentration in the concentration-response relationships for GABA indicated the developmental alteration of the GABA(A) receptor subunits and the channel density. The GABA-induced E(Cl-) measured by the gramicidin perforated patch mode shifted to more negative with development. The decay time constant of GABAergic inhibitory postsynaptic spontaneous currents (sIPSCs) in the synaptic active zone accelerated with aging. The GABA-induced currents were potentiated in a concentration dependent manner in the presence of benzodiazepine (BZP) agonists, diazepam (DZP) and zolpidem (ZPM). The potentiation rate of DZP on the GABA(A) response decreased with aging, but not in the case of ZPM, which demonstrated a stronger action in the aging rat neurons. These results suggested that the GABA(A) receptor x Cl- channel complexes may thus change both the assembly and interaction of subunits as well as their functional roles with aging.
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Affiliation(s)
- J S Rhee
- Department of Physiology, Faculty of Medicine, Kyushu University, Fukuoka, Japan
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Giovannini MG, Giovannelli L, Bianchi L, Kalfin R, Pepeu G. Glutamatergic modulation of cortical acetylcholine release in the rat: a combined in vivo microdialysis, retrograde tracing and immunohistochemical study. Eur J Neurosci 1997; 9:1678-89. [PMID: 9283822 DOI: 10.1111/j.1460-9568.1997.tb01525.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The microdialysis technique with one or two probes was used to investigate the modulation of cortically projecting cholinergic neurons by glutamatergic input in the rat in vivo. Male albino Wistar rats (250-300 g) were used. Under chloral hydrate anaesthesia microdialysis membranes were positioned in the parietal cortex, nucleus basalis magnocellularis (NBM) or medial septum. Acetylcholine was assayed using high-performance liquid chromatography (HPLC) with electrochemical detection while GABA was detected using HPLC with fluorimetric detection after derivatization of the amino acid with o-phthalaldehyde. Septo-cortical neurons were retrogradely labelled with fluoro-gold. Double labelling with choline acetyltransferase (ChAT) immunoreactivity was performed to identify these neurons. Our main findings were that: (i) i.c.v. administration of the NMDA antagonist 3-((R)-2-carboxypiperazin-4-yl)-propyl-1-phosphonic acid (CPP, 1-5 nmol) increased cortical acetylcholine outflow; (ii) local administration of CPP (100 microM) to the cortex had no effect on cortical acetylcholine outflow; (iii) local administration of CPP (100 microM) to the NBM decreased cortical acetylcholine outflow; (iv) local administration of CPP (100-200 microM) to the septum increased cortical GABA and acetylcholine outflow; (v) administration of muscimol to the septum prevented the effect of CPP on cortical acetylcholine outflow; (vi) retrograde tracing with fluoro-gold labelled cell bodies in the medial septum; (vii) septal fluoro-gold-positive neurons were not ChAT-immunoreactive. Our in vivo neurochemical results, in combination with retrograde tracing and immunohistochemistry, indicate that the cortically projecting cholinergic system is indirectly regulated by a glutamatergic input via a polysynaptic GABAergic circuitry located in the septum.
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Affiliation(s)
- M G Giovannini
- Department of Preclinical and Clinical Pharmacology, University of Florence, Italy
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Vaucher E, Linville D, Hamel E. Cholinergic basal forebrain projections to nitric oxide synthase-containing neurons in the rat cerebral cortex. Neuroscience 1997; 79:827-36. [PMID: 9219945 DOI: 10.1016/s0306-4522(97)00033-x] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Stimulation of basal forebrain neurons elicits regional cerebral blood flow increases which are reportedly mediated by acetylcholine and nitric oxide. However, the modality of interaction between these two mediators remains unclear. Particularly, little is known about the source, i.e. endothelial, glial and/or neuronal, of the potent gaseous vasodilator nitric oxide. In the present study, we examined, by double immunocytochemical labelling of nitric oxide synthase and choline acteyltransferase at the light and electron microscopic level, the existence of morphological relationships between cortical nitric oxide synthase-containing neurons and cholinergic cells or nerve fibres. Using anterograde tract tracing and selective basal forebrain lesions, we further investigated the origin of the cholinergic input to cortical nitric oxide synthase neurons. The results confirm that cortical nitric oxide synthase-immunoreactive neurons are often associated with the local microvascular bed, show that intracortical neurons immunostained for nitric oxide synthase and choline acetyltransferase belong to two distinct neuronal populations and, further, that a subset of nitric oxide synthase-containing cell bodies and their proximal dendrites receive a cholinergic input which originates primarily from basalocortical projections. Altogether, these findings suggest that cholinergic basal forebrain neurons could increase cortical blood flow partly via a local nitric oxide relay neuron whereby the freely diffusing gas would be the direct smooth muscle vasodilator agent. It is concluded that this interaction might contribute to the complex relationships between the basal forebrain and the cortical microcirculation, interactions which result in fine regulation of cortical perfusion.
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Affiliation(s)
- E Vaucher
- Neurobiology Unit, Montreal Neurological Institute, McGill University, Québec, Canada
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Abstract
Narcolepsy-cataplexy is a disabling neurological disorder that affects 1/2000 individuals. The main clinical features of narcolepsy, excessive daytime sleepiness and symptoms of abnormal REM sleep (cataplexy, sleep paralysis, hypnagogic hallucinations) are currently treated using amphetamine-like compounds or modafinil and antidepressants. Pharmacological research in the area is facilitated greatly by the existence of a canine model of the disorder. The mode of action of these compounds involves presynaptic activation of adrenergic transmission for the anticataplectic effects of antidepressant compounds and presynaptic activation of dopaminergic transmission for the EEG arousal effects of amphetamine-like stimulants. The mode of action of modafmil is still uncertain, and other neurochemical systems may offer interesting avenues for therapeutic development. Pharmacological and physiological studies using the canine model have identified primary neurochemical and neuroanatomical systems that underlie the expression of abnormal REM sleep and excessive sleepiness in narcolepsy. These involve mostly the pontine and basal forebrain cholinergic, the pontine adrenergic and the mesolimbic and mesocortical dopaminergic systems. These studies confirm a continuing need for basic research in both human and canine narcolepsy, and new treatments that act directly at the level of the primary defect in narcolepsy might be forthcoming.
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Affiliation(s)
- S Nishino
- Stanford Center for Narcolepsy, Palo Alto, CA 94304, USA
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