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Projections from the nucleus accumbens shell to the ventral pallidum are involved in the control of sucrose intake in adult female rats. Brain Struct Funct 2020; 225:2815-2839. [PMID: 33124673 DOI: 10.1007/s00429-020-02161-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Accepted: 10/15/2020] [Indexed: 12/28/2022]
Abstract
In rodents, stimulation of the nucleus accumbens shell (AcbSh) directly or via its projection to the lateral hypothalamus (LH) attenuates food intake. The ventral pallidum (VP) receives dense projections from the AcbSh and is sensitive to the hedonic aspect of food and motivation for reward. However, the role of accumbal projections to the VP in the regulation of food intake was not well investigated. In the present study conducted on female rats, we examined the effects of stimulation of the AcbSh using optogenetics, or pharmacological inhibition of the rostral VP, or stimulation of projections from the AcbSh to the rostral VP using optogenetics on the consumption of 10% sucrose, lick microstructure and the expression of c-fos mRNA. Stimulation of the AcbSh, inhibition of the rostral VP with muscimol, or stimulation of axonal terminals from the AcbSh to the rostral VP resulted in a decrease in sucrose intake, meal duration, and total number of licks. The licking microstructure analysis showed that optogenetic stimulation of AcbSh or axonal terminals from the AcbSh to the rostral VP decreased the hedonic value of the sucrose. However, inhibition of the rostral VP decreased the motivation, whereas stimulation of the accumbal projections in the rostral VP increased the motivation to drink. This difference could be due to differential involvement of GABAergic and glutamatergic VP neurons. Stimulation of the AcbSh resulted in a decrease of c-fos mRNA expression in the LH and rostral VP, and stimulation of axonal terminals from the AcbSh to the rostral VP decreased c-fos mRNA expression only in the rostral VP. This study demonstrates that in adult female rats, in addition to the already known role of the AcbSh projections to the LH, AcbSh projections to the VP play a major role in the regulation of sucrose intake.
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Keimpema E, Zheng K, Barde SS, Berghuis P, Dobszay MB, Schnell R, Mulder J, Luiten PGM, Xu ZD, Runesson J, Langel Ü, Lu B, Hökfelt T, Harkany T. GABAergic terminals are a source of galanin to modulate cholinergic neuron development in the neonatal forebrain. ACTA ACUST UNITED AC 2013; 24:3277-88. [PMID: 23897649 DOI: 10.1093/cercor/bht192] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The distribution and (patho-)physiological role of neuropeptides in the adult and aging brain have been extensively studied. Galanin is an inhibitory neuropeptide that can coexist with γ-aminobutyric acid (GABA) in the adult forebrain. However, galanin's expression sites, mode of signaling, impact on neuronal morphology, and colocalization with amino acid neurotransmitters during brain development are less well understood. Here, we show that galaninergic innervation of cholinergic projection neurons, which preferentially express galanin receptor 2 (GalR2) in the neonatal mouse basal forebrain, develops by birth. Nerve growth factor (NGF), known to modulate cholinergic morphogenesis, increases GalR2 expression. GalR2 antagonism (M871) in neonates reduces the in vivo expression and axonal targeting of the vesicular acetylcholine transporter (VAChT), indispensable for cholinergic neurotransmission. During cholinergic neuritogenesis in vitro, GalR2 can recruit Rho-family GTPases to induce the extension of a VAChT-containing primary neurite, the prospective axon. In doing so, GalR2 signaling dose-dependently modulates directional filopodial growth and antagonizes NGF-induced growth cone differentiation. Galanin accumulates in GABA-containing nerve terminals in the neonatal basal forebrain, suggesting its contribution to activity-driven cholinergic development during the perinatal period. Overall, our data define the cellular specificity and molecular complexity of galanin action in the developing basal forebrain.
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Affiliation(s)
- Erik Keimpema
- Department of Neuroscience, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm SE-17177, Sweden
| | | | | | - Paul Berghuis
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm SE-17177, Sweden
| | - Márton B Dobszay
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm SE-17177, Sweden
| | - Robert Schnell
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm SE-17177, Sweden
| | - Jan Mulder
- Department of Neuroscience, Science for Life Laboratory, Royal Institute of Technology, Stockholm SE-17121, Sweden
| | - Paul G M Luiten
- Department of Molecular Neurobiology, University of Groningen, Groningen NL-9747 AG, The Netherlands
| | - Zhiqing David Xu
- Department of Neuroscience, Beijing Institute for Neuroscience, Beijing Center for Neural Regeneration and Repairing, Department of Neurobiology, Capital Medical University, Beijing 100069, China
| | - Johan Runesson
- Department of Neurochemistry, Stockholm University, Stockholm SE-10691, Sweden and
| | - Ülo Langel
- Department of Neurochemistry, Stockholm University, Stockholm SE-10691, Sweden and
| | - Bai Lu
- R&D China, GlaxoSmithKline, Pudong, Shanghai 201203, China
| | | | - Tibor Harkany
- Department of Neuroscience, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm SE-17177, Sweden
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Ghorbel MT, Becker KG, Henley JM. Profile of changes in gene expression in cultured hippocampal neurones evoked by the GABAB receptor agonist baclofen. Physiol Genomics 2005. [PMID: 15784695 DOI: 10.1152/physiol] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Metabotropic gamma-aminobutyric acid receptors (GABA(B)Rs) play a critical role in inhibitory synaptic transmission in the hippocampus. However, little is known about a possible long-term effect requiring transcriptional changes. Here, using microarray technology and RT-PCR of RNA from cultured rat embryonic hippocampal neurones, we report the profile of genes that are up- or downregulated by activation of GABA(B)Rs by baclofen but are not changed by baclofen in the presence of the GABA(B)R antagonist CGP-55845A. Our data show, for the first time, regulation of transcription of defined mRNAs after specific GABA(B) receptor activation. The identified genes can be grouped into those encoding signal transduction, endocytosis/trafficking, and structural classes of proteins. For example, butyrylcholinesterase, brain-derived neurotrophic factor, and COPS5 (Jab1) genes were upregulated, whereas Rab8 interacting protein and Rho GTPase-activating protein 4 were downregulated. These results provide important baseline genomic data for future studies aimed at investigating the long-term effects of GABA(B)R activation in neurones such as their roles in neuronal growth, pathway formation and stabilization, and synaptic plasticity.
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Affiliation(s)
- Mohamed T Ghorbel
- Medical Research Council Centre for Synaptic Plasticity, Department of Anatomy, School of Medical Sciences, University of Bristol, Bristol, United Kingdom
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Ghorbel MT, Becker KG, Henley JM. Profile of changes in gene expression in cultured hippocampal neurones evoked by the GABAB receptor agonist baclofen. Physiol Genomics 2005; 22:93-8. [PMID: 15784695 PMCID: PMC1563181 DOI: 10.1152/physiolgenomics.00202.2004] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Metabotropic gamma-aminobutyric acid receptors (GABA(B)Rs) play a critical role in inhibitory synaptic transmission in the hippocampus. However, little is known about a possible long-term effect requiring transcriptional changes. Here, using microarray technology and RT-PCR of RNA from cultured rat embryonic hippocampal neurones, we report the profile of genes that are up- or downregulated by activation of GABA(B)Rs by baclofen but are not changed by baclofen in the presence of the GABA(B)R antagonist CGP-55845A. Our data show, for the first time, regulation of transcription of defined mRNAs after specific GABA(B) receptor activation. The identified genes can be grouped into those encoding signal transduction, endocytosis/trafficking, and structural classes of proteins. For example, butyrylcholinesterase, brain-derived neurotrophic factor, and COPS5 (Jab1) genes were upregulated, whereas Rab8 interacting protein and Rho GTPase-activating protein 4 were downregulated. These results provide important baseline genomic data for future studies aimed at investigating the long-term effects of GABA(B)R activation in neurones such as their roles in neuronal growth, pathway formation and stabilization, and synaptic plasticity.
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Affiliation(s)
- Mohamed T Ghorbel
- Medical Research Council Centre for Synaptic Plasticity, Department of Anatomy, School of Medical Sciences, University of Bristol, Bristol, United Kingdom
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Suzuki T, Takagi R, Kawashima K. Picrotoxin increased acetylcholine release from rat cultured embryonic septal neurons. Neurosci Lett 2004; 356:57-60. [PMID: 14746901 DOI: 10.1016/j.neulet.2003.11.031] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
GABA is a major inhibitory neurotransmitter in the mature mammalian brain. In the early stages of brain development, it has been reported that GABA(A) receptor stimulation and the associated increase in Cl(-) conductance lead to membrane depolarization. In this study, we tested the effects of picrotoxin, a GABA(A) receptor Cl(-) channel blocker, on spontaneously released acetylcholine (ACh) from cultured rat embryonic septal cells. Picrotoxin increased spontaneously released ACh. These results indicate that blockade of GABA-activated Cl(-) channel increases neuronal excitability even in an early stage of the development.
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Affiliation(s)
- Takeshi Suzuki
- Department of Pharmacology, Kyoritsu College of Pharmacy, 1-5-30 Shibakoen, Minato-ku, Tokyo 105-8512, Japan.
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