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Castro DC, Bruchas MR. A Motivational and Neuropeptidergic Hub: Anatomical and Functional Diversity within the Nucleus Accumbens Shell. Neuron 2019; 102:529-552. [PMID: 31071288 PMCID: PMC6528838 DOI: 10.1016/j.neuron.2019.03.003] [Citation(s) in RCA: 142] [Impact Index Per Article: 28.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Revised: 02/22/2019] [Accepted: 03/01/2019] [Indexed: 01/14/2023]
Abstract
The mesocorticolimbic pathway is canonically known as the "reward pathway." Embedded within the center of this circuit is the striatum, a massive and complex network hub that synthesizes motivation, affect, learning, cognition, stress, and sensorimotor information. Although striatal subregions collectively share many anatomical and functional similarities, it has become increasingly clear that it is an extraordinarily heterogeneous region. In particular, the nucleus accumbens (NAc) medial shell has repeatedly demonstrated that the rules dictated by more dorsal aspects of the striatum do not apply or are even reversed in functional logic. These discrepancies are perhaps most easily captured when isolating the functions of various neuromodulatory peptide systems within the striatum. Endogenous peptides are thought to play a critical role in modulating striatal signals to either amplify or dampen evoked behaviors. Here we describe the anatomical-functional backdrop upon which several neuropeptides act within the NAc to modulate behavior, with a specific emphasis on nucleus accumbens medial shell and stress responsivity. Additionally, we propose that, as the field continues to dissect fast neurotransmitter systems within the NAc, we must also provide considerable contextual weight to the roles local peptides play in modulating these circuits to more comprehensively understand how this important subregion gates motivated behaviors.
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Affiliation(s)
- Daniel C Castro
- Center for Neurobiology of Addiction, Pain, and Emotion, University of Washington, Seattle, WA 98195, USA; Department of Anesthesiology and Pain Medicine, University of Washington, Seattle, WA 98195, USA; Department of Pharmacology, University of Washington, Seattle, WA 98195, USA
| | - Michael R Bruchas
- Center for Neurobiology of Addiction, Pain, and Emotion, University of Washington, Seattle, WA 98195, USA; Department of Anesthesiology and Pain Medicine, University of Washington, Seattle, WA 98195, USA; Department of Pharmacology, University of Washington, Seattle, WA 98195, USA.
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Transcriptional and physiological adaptations in nucleus accumbens somatostatin interneurons that regulate behavioral responses to cocaine. Nat Commun 2018; 9:3149. [PMID: 30089879 PMCID: PMC6082848 DOI: 10.1038/s41467-018-05657-9] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2017] [Accepted: 07/12/2018] [Indexed: 11/20/2022] Open
Abstract
The role of somatostatin interneurons in nucleus accumbens (NAc), a key brain reward region, remains poorly understood due to the fact that these cells account for < 1% of NAc neurons. Here, we use optogenetics, electrophysiology, and RNA-sequencing to characterize the transcriptome and functioning of NAc somatostatin interneurons after repeated exposure to cocaine. We find that the activity of somatostatin interneurons regulates behavioral responses to cocaine, with repeated cocaine reducing the excitability of these neurons. Repeated cocaine also induces transcriptome-wide changes in gene expression within NAc somatostatin interneurons. We identify the JUND transcription factor as a key regulator of cocaine action and confirmed, by use of viral-mediated gene transfer, that JUND activity in somatostatin interneurons influences behavioral responses to cocaine. Our results identify alterations in NAc induced by cocaine in a sparse population of somatostatin interneurons, and illustrate the value of studying brain diseases using cell type-specific whole transcriptome RNA-sequencing. While making up a small percentage of neurons in the nucleus accumbens, somatostatin interneurons may have important function in dopamine- and addiction-related behavior. Here, Ribeiro and colleagues show that somatostatin interneurons regulate behavioral responses to cocaine with physiological and transcriptomic changes.
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Ionov ID, Pushinskaya II, Roslavtseva LA, Severtsev NN. Brain sites mediating cyclosomatostatin-induced catalepsy in Wistar rats: A specific role for the nigrostriatal system and locus coeruleus. Brain Res 2018; 1691:26-33. [PMID: 29680272 DOI: 10.1016/j.brainres.2018.04.016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Revised: 04/13/2018] [Accepted: 04/16/2018] [Indexed: 02/05/2023]
Abstract
A decrease in somatostatin activity is observed in the Parkinsonian brain. In recent experiments on rats, we simulated this abnormality by intracerebroventricular injections of a somatostatin antagonist, cyclosomatostatin. The treated animals displayed catalepsy, a state that resembles the extrapyramidal signs of Parkinson's disease. The neuroanatomical substrates mediating the catalepsy-inducing effect of cyclosomatostatin are unknown. To clarify this issue, we assessed here the action of cyclosomatostatin injected into the substantia nigra pars compacta (SNc), dorsal striatum (DS), locus coeruleus (LC), pedunculopontine tegmental nucleus (PPTg), and inferior colliculus (IC). The experiments were conducted with male Wistar rats of 270-290 g bw, catalepsy was evaluated by using the bar test. The injections into the PPTg and IC were without effect whereas the intra-SNc, intra-DS, and intra-LC administrations produced distinct cataleptic response. Thus, it was shown for the first time that the LC is a brain center capable of causing catalepsy. These data provide new insights into the neuroanatomical organization of the catalepsy-initiating mechanism and suggest the LC representing a potential target for therapeutic manipulations of extrapyramidal dysfunctions.
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Affiliation(s)
- Ilya D Ionov
- Centre on Theoretical Problems in Physical and Chemical Pharmacology, Russian Academy of Sciences, Moscow, Russia.
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Smith ACW, Scofield MD, Heinsbroek JA, Gipson CD, Neuhofer D, Roberts-Wolfe DJ, Spencer S, Garcia-Keller C, Stankeviciute NM, Smith RJ, Allen NP, Lorang MR, Griffin WC, Boger HA, Kalivas PW. Accumbens nNOS Interneurons Regulate Cocaine Relapse. J Neurosci 2017; 37:742-756. [PMID: 28123012 PMCID: PMC5296777 DOI: 10.1523/jneurosci.2673-16.2016] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Revised: 11/16/2016] [Accepted: 11/30/2016] [Indexed: 12/31/2022] Open
Abstract
Relapse to drug use can be initiated by drug-associated cues. The intensity of cue-induced relapse is correlated with the induction of transient synaptic potentiation (t-SP) at glutamatergic synapses on medium spiny neurons (MSNs) in the nucleus accumbens core (NAcore) and requires spillover of glutamate from prefrontal cortical afferents. We used a rodent self-administration/reinstatement model of relapse to show that cue-induced t-SP and reinstated cocaine seeking result from glutamate spillover, initiating a metabotropic glutamate receptor 5 (mGluR5)-dependent increase in nitric oxide (NO) production. Pharmacological stimulation of mGluR5 in NAcore recapitulated cue-induced reinstatement in the absence of drug-associated cues. Using NO-sensitive electrodes, mGluR5 activation by glutamate was shown to stimulate NO production that depended on activation of neuronal nitric oxide synthase (nNOS). nNOS is expressed in ∼1% of NAcore neurons. Using a transgene strategy to express and stimulate designer receptors that mimicked mGluR5 signaling through Gq in nNOS interneurons, we recapitulated cue-induced reinstatement in the absence of cues. Conversely, using a transgenic caspase strategy, the intensity of cue-induced reinstatement was correlated with the extent of selective elimination of nNOS interneurons. The induction of t-SP during cued reinstatement depends on activating matrix metalloproteinases (MMPs) and selective chemogenetic stimulation of nNOS interneurons recapitulated MMP activation and t-SP induction (increase in AMPA currents in MSNs). These data demonstrate critical involvement of a sparse population of nNOS-expressing interneurons in cue-induced cocaine seeking, revealing a bottleneck in brain processing of drug-associated cues where therapeutic interventions could be effective in treating drug addiction. SIGNIFICANCE STATEMENT Relapse to cocaine use in a rat model is associated with transient increases in synaptic strength at prefrontal cortex synapses in the nucleus accumbens. We demonstrate the sequence of events that mediates synaptic potentiation and reinstated cocaine seeking induced by cocaine-conditioned cues. Activation of prefrontal inputs to the accumbens by cues initiates spillover of synaptic glutamate, which stimulates metabotropic glutamate receptor 5 (mGluR5) on a small population of interneurons (∼1%) expressing neuronal nitric oxide synthase. Stimulating these glutamate receptors increases nitric oxide (NO) production, which stimulates matrix metalloprotease-2 (MMP-2) and MMP-9 activity in the extracellular space. Manipulating the interaction between mGluR5, NO production, or MMP-2 and MMP-9 pharmacologically or genetically is sufficient to recapitulate transient synaptic potentiation and reinstate cocaine seeking.
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Affiliation(s)
- Alexander C W Smith
- Department of Pharmacology and Systems Therapeutics, Icahn School of Medicine at Mount Sinai, New York, New York 10029
| | - Michael D Scofield
- Department of Neuroscience, Medical University of South Carolina, Charleston, South Carolina 29425
| | - Jasper A Heinsbroek
- Department of Neuroscience, Medical University of South Carolina, Charleston, South Carolina 29425
| | - Cassandra D Gipson
- Department of Psychology, Arizona State University, Tempe, Arizona 85287
| | - Daniela Neuhofer
- Department of Neuroscience, Medical University of South Carolina, Charleston, South Carolina 29425
| | - Doug J Roberts-Wolfe
- Department of Neuroscience, Medical University of South Carolina, Charleston, South Carolina 29425
| | - Sade Spencer
- Department of Neuroscience, Medical University of South Carolina, Charleston, South Carolina 29425
| | - Constanza Garcia-Keller
- Department of Neuroscience, Medical University of South Carolina, Charleston, South Carolina 29425
| | - Neringa M Stankeviciute
- Department of Neuroscience, Medical University of South Carolina, Charleston, South Carolina 29425
| | - Rachel J Smith
- Department of Psychology, Institute for Neuroscience, Texas A&M University, College Station, Texas 77843, and
| | - Nicholas P Allen
- Department of Biology, College of Charleston, Charleston, South Carolina 29401
| | - Melissa R Lorang
- Department of Biology, College of Charleston, Charleston, South Carolina 29401
| | - William C Griffin
- Department of Neuroscience, Medical University of South Carolina, Charleston, South Carolina 29425
| | - Heather A Boger
- Department of Neuroscience, Medical University of South Carolina, Charleston, South Carolina 29425
| | - Peter W Kalivas
- Department of Neuroscience, Medical University of South Carolina, Charleston, South Carolina 29425,
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Ionov ID, Pushinskaya II. Somatostatin antagonist induces catalepsy in the aged rat. Psychopharmacology (Berl) 2013; 227:273-6. [PMID: 23274508 DOI: 10.1007/s00213-012-2961-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/15/2012] [Accepted: 12/14/2012] [Indexed: 02/02/2023]
Abstract
RATIONALE Extrapyramidal motor signs are the major features of Parkinson's disease (PD). It is unclear whether there is a link between these signs and such PD-associated factors as brain somatostatin deficiency and aging. OBJECTIVES This study aimed to examine whether an inhibition of the brain somatostatin system can initiate catalepsy, a model of extrapyramidal disorders, in young and aged rats. METHODS The animals of 100-110 and 540-560 days of age were used. Catalepsy was measured using the bar test. The inhibition of the brain somatostatin activity was simulated by intracerebroventricular administration of a somatostatin antagonist, cyclosomatostatin. RESULTS Cyclosomatostatin dose-dependently induced catalepsy in aged, but not in young rats. The cataleptic response was reversed by a somatostatin analog, octreotide. CONCLUSIONS The combination of aging and brain somatostatin deficiency can lead to catalepsy in rats. Since both factors are frequently observed in PD patients, the present results might be of relevance for pathogenesis of extrapyramidal signs in this disease.
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Affiliation(s)
- Ilya D Ionov
- Centre on Theoretical Problems in Physical and Chemical Pharmacology, Russian Academy of Sciences, Leninsky Prospect 123-4-63, Moscow, 117513, Russia.
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Somatostatin antagonist potentiates haloperidol-induced catalepsy in the aged rat. Pharmacol Biochem Behav 2012; 103:295-8. [DOI: 10.1016/j.pbb.2012.08.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/06/2012] [Revised: 08/02/2012] [Accepted: 08/11/2012] [Indexed: 11/18/2022]
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Yamashita A, Fuchs E, Taira M, Yamamoto T, Hayashi M. Somatostatin-immunoreactive senile plaque-like structures in the frontal cortex and nucleus accumbens of aged tree shrews and Japanese macaques. J Med Primatol 2012; 41:147-57. [PMID: 22512242 DOI: 10.1111/j.1600-0684.2012.00540.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
BACKGROUND Previously, we demonstrated decreased expression of somatostatin mRNA in aged macaque brain, particularly in the prefrontal cortex. To investigate whether or not this age-dependent decrease in mRNA is related to morphological changes, we analyzed somatostatin cells in the cerebra of aged Japanese macaques and compared them with those in rats and tree shrews, the latter of which are closely related to primates. METHODS Brains of aged macaques, tree shrews, and rats were investigated by immunohistochemistry with special emphasis on somatostatin. RESULTS We observed degenerating somatostatin-immunoreactive cells in the cortices of aged macaques and tree shrews. Somatostatin-immunoreactive senile plaque-like structures were found in areas 6 and 8 and in the nucleus accumbens of macaques, as well as in the nucleus accumbens and the cortex of aged tree shrews, where amyloid accumulations were observed. CONCLUSIONS Somatostatin degenerations may be related to amyloid accumulations and may play roles in impairments of cognitive functions during aging.
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Affiliation(s)
- Akiko Yamashita
- Division of Applied System Neuroscience, Nihon University School of Medicine, Tokyo, Japan.
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Ikeda H, Kamei J, Koshikawa N, Cools AR. Nucleus Accumbens and Dopamine-Mediated Turning Behavior of the Rat: Role of Accumbal Non-dopaminergic Receptors. J Pharmacol Sci 2012; 120:152-64. [DOI: 10.1254/jphs.12r02cr] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
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Nakano-Tateno T, Shichiri M, Suzuki-Kemuriyama N, Tani Y, Izumiyama H, Hirata Y. Prolonged effects of intracerebroventricular angiotensin II on drinking, eating and locomotor behavior in mice. ACTA ACUST UNITED AC 2011; 173:86-92. [PMID: 22001077 DOI: 10.1016/j.regpep.2011.09.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2011] [Revised: 09/17/2011] [Accepted: 09/29/2011] [Indexed: 12/16/2022]
Abstract
The effects of centrally administered Angiotensin II (Ang II) on water and food intake in rodent models are well known. However, most studies have focused on the acute effects of intracranial Ang II. In the current study, we evaluated the effects of intracerebroventricular Ang II on food and water intake as well as locomotor activity over the entire dark phase of the murine diurnal cycle. Consistent with the previous reports, centrally administered Ang II rapidly stimulated water intake over the initial 1-hour period following treatment. However, this acute increase was immediately followed by a marked reduction in water intake resulting in decreased cumulative water intake approximately 7h after Ang II treatment. Pretreating animals with an Ang II type 1 receptor blocker, Losartan, completely antagonized the acute effect of Ang II and abolished initial water intake. In contrast, application of an Ang II type 2 receptor blocker, PD123319, abrogated the prolonged inhibitory effect of Ang II on drinking behavior and partially suppressed the initial increases in water intake. The suppressive effects of Ang II on cumulative food intake and spontaneous physical activity were also evident throughout the entire dark phase of diurnal cycle. These experiments are the first to suggest that the stimulatory effect of central Ang II treatment on water consumption is very temporary and that it causes a sustained suppressive effect on voluntary locomotion and food intake behavior in mice.
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Affiliation(s)
- Tae Nakano-Tateno
- Department of Clinical and Molecular Endocrinology, Tokyo Medical and Dental University Graduate School, Tokyo 113-8519, Japan
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Semenova S, Hoyer D, Geyer MA, Markou A. Somatostatin-28 modulates prepulse inhibition of the acoustic startle response, reward processes and spontaneous locomotor activity in rats. Neuropeptides 2010; 44:421-9. [PMID: 20537385 PMCID: PMC3215674 DOI: 10.1016/j.npep.2010.04.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2009] [Revised: 04/28/2010] [Accepted: 04/29/2010] [Indexed: 11/30/2022]
Abstract
Somatostatins have been shown to be involved in the pathophysiology of motor and affective disorders, as well as psychiatric disorders, including schizophrenia. We hypothesized that in addition to motor function, somatostatin may be involved in somatosensory gating and reward processes that have been shown to be dysregulated in schizophrenia. Accordingly, we evaluated the effects of intracerebroventricular administration of somatostatin-28 on spontaneous locomotor and exploratory behavior measured in a behavioral pattern monitor, sensorimotor gating, prepulse inhibition (PPI) of the acoustic startle reflex, and brain reward function (measured in a discrete trial intracranial self-stimulation procedure) in rats. Somatostatin-28 decreased spontaneous locomotor activity during the first 10 min of a 60 min testing session with no apparent changes in the exploratory activity of rats. The highest somatostatin-28 dose (10 microg/5 microl/side) induced PPI deficits with no effect on the acoustic startle response or startle response habituation. The somatostatin-induced PPI deficit was partially reversed by administration of SRA-880, a selective somatostatin 1 (sst(1)) receptor antagonist. Somatostatin-28 also induced elevations in brain reward thresholds, reflecting an anhedonic-like state. The non-peptide sst(1) receptor antagonist SRA-880 had no effect on brain reward function under baseline conditions. Altogether these findings suggest that somatostatin-28 modulates PPI and brain reward function but does not have a robust effect on spontaneous exploratory activity. Thus, increases in somatostatin transmission may represent one of the neurochemical mechanisms underlying anhedonia, one of the negative symptoms of schizophrenia, and sensorimotor gating deficits associated with cognitive impairments in schizophrenia patients.
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Affiliation(s)
- Svetlana Semenova
- Department of Psychiatry, University of California San Diego, La Jolla, CA 92093, USA.
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Goebel M, Stengel A, Wang L, Coskun T, Alsina-Fernandez J, Rivier J, Taché Y. Pattern of Fos expression in the brain induced by selective activation of somatostatin receptor 2 in rats. Brain Res 2010; 1351:150-164. [PMID: 20637739 DOI: 10.1016/j.brainres.2010.07.024] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2010] [Revised: 06/28/2010] [Accepted: 07/08/2010] [Indexed: 02/08/2023]
Abstract
Central activation of somatostatin (sst) receptors by oligosomatostatin analogs inhibits growth hormone and stress-related rise in catecholamine plasma levels while stimulating grooming, feeding behaviors, gastric transit and acid secretion, which can be mimicked by selective sst(2) receptor agonist. To evaluate the pattern of neuronal activation induced by peptide sst receptor agonists, we assessed Fos-expression in rat brain after intracerebroventricular (i.c.v.) injection of a newly developed selective sst(2) agonist compared to the oligosomatostatin ODT8-SST, a pan-sst(1-5) agonist. Ninety min after injection of vehicle (10 microl) or previously established maximal orexigenic dose of peptides (1 microg=1 nmol/rat), brains were assessed for Fos-immunohistochemistry and doublelabeling. Food and water were removed after injection. The sst(2) agonist and ODT8-SST induced a similar Fos distribution pattern except in the arcuate nucleus where only the sst(2) agonist increased Fos. Compared to ODT8-SST, the sst(2) agonist induced higher Fos-expression by 3.7-times in the basolateral amygdaloid nucleus, 1.2-times in the supraoptic nucleus (SON), 1.6-times in the magnocellular paraventricular hypothalamic nucleus (mPVN), 4.1-times in the external lateral parabrachial nucleus, and 2.6-times in both the inferior olivary nucleus and superficial layer of the caudal spinal trigeminal nucleus. Doublelabeling in the hypothalamus showed that ODT8-SST activates 36% of oxytocin, 63% of vasopressin and 79% of sst(2) immunoreactive neurons in the mPVN and 28%, 55% and 25% in the SON, respectively. Selective activation of sst(2) receptor results in a more robust neuronal activation than the pan-sst(1-5) agonist in various brain regions that may have relevance in sst(2) mediated alterations of behavioral, autonomic and endocrine functions.
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Affiliation(s)
- Miriam Goebel
- CURE/Digestive Diseases Research Center, Center for Neurobiology of Stress, Digestive Diseases Division, Department of Medicine, David Geffen School of Medicine, UCLA and VA Greater Los Angeles Healthcare System, Los Angeles, California, USA
| | - Andreas Stengel
- CURE/Digestive Diseases Research Center, Center for Neurobiology of Stress, Digestive Diseases Division, Department of Medicine, David Geffen School of Medicine, UCLA and VA Greater Los Angeles Healthcare System, Los Angeles, California, USA
| | - Lixin Wang
- CURE/Digestive Diseases Research Center, Center for Neurobiology of Stress, Digestive Diseases Division, Department of Medicine, David Geffen School of Medicine, UCLA and VA Greater Los Angeles Healthcare System, Los Angeles, California, USA
| | - Tamer Coskun
- Biotechnology Discovery Research, Eli Lilly and Company, Indianapolis, IN, USA
| | | | - Jean Rivier
- Peptide Biology Laboratories, Salk Institute, La Jolla, CA, USA
| | - Yvette Taché
- CURE/Digestive Diseases Research Center, Center for Neurobiology of Stress, Digestive Diseases Division, Department of Medicine, David Geffen School of Medicine, UCLA and VA Greater Los Angeles Healthcare System, Los Angeles, California, USA.
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Ikeda H, Kotani A, Koshikawa N, Cools A. Differential role of GABAA and GABAB receptors in two distinct output stations of the rat striatum: studies on the substantia nigra pars reticulata and the globus pallidus. Neuroscience 2010; 167:31-9. [DOI: 10.1016/j.neuroscience.2010.01.054] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2009] [Revised: 01/07/2010] [Accepted: 01/25/2010] [Indexed: 10/19/2022]
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