201
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Comparison of immunoreactivities of calbindin-D28k, calretinin and parvalbumin in the striatum between young, adult and aged mice, rats and gerbils. Neurochem Res 2015; 40:864-72. [PMID: 25676337 DOI: 10.1007/s11064-015-1537-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2014] [Revised: 12/10/2014] [Accepted: 02/06/2015] [Indexed: 12/13/2022]
Abstract
Calcium binding proteins play important roles in all aspects of neural functioning in the central nervous system. In the present study, we examined age-related changes of three different calcium binding proteins calbindin-D28k (CB), calretinin (CR) and parvalbumin (PV) immunoreactivities in the striatum of young (1 month), adult (6 months) and aged (24 months) ages in three species of rodents (mouse, rat and gerbil) using immunohistochemistry and Western blotting. Our results show that the number of CB-immunoreactive neurons was highest in the adult mouse and rat; however, in the gerbil, the number of CB-immunoreactive neurons was not significantly different from each group although the CB immunoreactivity was significantly decreased in the aged group compared with the adult group. The number of CR-immunoreactive neurons in the striatum was significantly highest in all the adult groups, and, especially, the number of CR-immunoreactive neurons and CR immunoreactivity in the aged gerbil were significantly decreased in the aged group compared with the other groups. Finally, we did not found any significant difference in the number of PV-immunoreactive neurons in the striatum with age among the three rodents. On the other hand, we found that protein levels of three calcium binding proteins in all the mouse groups were similar to the immunohistochemical data. These results indicate that the distribution pattern of calcium binding proteins is different according to age; the adult might show an apparent tendency of high expression in the striatum.
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202
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Modulation of direct pathway striatal projection neurons by muscarinic M4-type receptors. Neuropharmacology 2015; 89:232-44. [DOI: 10.1016/j.neuropharm.2014.09.028] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2014] [Revised: 09/12/2014] [Accepted: 09/23/2014] [Indexed: 12/29/2022]
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203
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Waldvogel H, Faull R. The Diversity of GABAA Receptor Subunit Distribution in the Normal and Huntington's Disease Human Brain1. DIVERSITY AND FUNCTIONS OF GABA RECEPTORS: A TRIBUTE TO HANNS MÖHLER, PART B 2015; 73:223-64. [DOI: 10.1016/bs.apha.2014.11.010] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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204
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Human and monkey striatal interneurons are derived from the medial ganglionic eminence but not from the adult subventricular zone. J Neurosci 2014; 34:10906-23. [PMID: 25122892 DOI: 10.1523/jneurosci.1758-14.2014] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
In adult rodent and monkey brains, newly born neurons in the subventricular zone (SVZ) in the wall of the lateral ventricle migrate into the olfactory bulb (OB) via the rostral migratory stream (RMS). A recent study reported that interneurons are constantly generating in the adult human striatum from the SVZ. In contrast, by taking advantage of the continuous expression of Sp8 from the neuroblast stage through differentiation into mature interneurons, we found that the adult human SVZ does not generate new interneurons for the striatum. In the adult human SVZ and RMS, very few neuroblasts were observed, and most of them expressed the transcription factor Sp8. Neuroblasts in the adult rhesus monkey SVZ-RMS-OB pathway also expressed Sp8. In addition, we observed that Sp8 was expressed by most adult human and monkey OB interneurons. However, very few Sp8+ cells were in the adult human striatum. This suggests that neuroblasts in the adult human SVZ and RMS are likely destined for the OB, but not for the striatum. BrdU-labeling results also revealed few if any newly born neurons in the adult rhesus monkey striatum. Finally, on the basis of transcription factor expression, we provide strong evidence that the vast majority of interneurons in the human and monkey striatum are generated from the medial ganglionic eminence during embryonic developmental stages, as they are in rodents. We conclude that, although a small number of neuroblasts exist in the adult human SVZ, they do not migrate into the striatum and become mature striatal interneurons.
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205
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Moyer JT, Halterman BL, Finkel LH, Wolf JA. Lateral and feedforward inhibition suppress asynchronous activity in a large, biophysically-detailed computational model of the striatal network. Front Comput Neurosci 2014; 8:152. [PMID: 25505406 PMCID: PMC4243567 DOI: 10.3389/fncom.2014.00152] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Accepted: 11/04/2014] [Indexed: 12/03/2022] Open
Abstract
Striatal medium spiny neurons (MSNs) receive lateral inhibitory projections from other MSNs and feedforward inhibitory projections from fast-spiking, parvalbumin-containing striatal interneurons (FSIs). The functional roles of these connections are unknown, and difficult to study in an experimental preparation. We therefore investigated the functionality of both lateral (MSN-MSN) and feedforward (FSI-MSN) inhibition using a large-scale computational model of the striatal network. The model consists of 2744 MSNs comprised of 189 compartments each and 121 FSIs comprised of 148 compartments each, with dendrites explicitly represented and almost all known ionic currents included and strictly constrained by biological data as appropriate. Our analysis of the model indicates that both lateral inhibition and feedforward inhibition function at the population level to limit non-ensemble MSN spiking while preserving ensemble MSN spiking. Specifically, lateral inhibition enables large ensembles of MSNs firing synchronously to strongly suppress non-ensemble MSNs over a short time-scale (10–30 ms). Feedforward inhibition enables FSIs to strongly inhibit weakly activated, non-ensemble MSNs while moderately inhibiting activated ensemble MSNs. Importantly, FSIs appear to more effectively inhibit MSNs when FSIs fire asynchronously. Both types of inhibition would increase the signal-to-noise ratio of responding MSN ensembles and contribute to the formation and dissolution of MSN ensembles in the striatal network.
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Affiliation(s)
- Jason T Moyer
- Department of Bioengineering, University of Pennsylvania Philadelphia, PA, USA
| | | | - Leif H Finkel
- Department of Bioengineering, University of Pennsylvania Philadelphia, PA, USA
| | - John A Wolf
- Department of Neurosurgery, University of Pennsylvania Philadelphia, PA, USA
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206
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Toledo-Suárez C, Duarte R, Morrison A. Liquid computing on and off the edge of chaos with a striatal microcircuit. Front Comput Neurosci 2014; 8:130. [PMID: 25484864 PMCID: PMC4240071 DOI: 10.3389/fncom.2014.00130] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2013] [Accepted: 09/26/2014] [Indexed: 01/12/2023] Open
Abstract
In reinforcement learning theories of the basal ganglia, there is a need for the expected rewards corresponding to relevant environmental states to be maintained and modified during the learning process. However, the representation of these states that allows them to be associated with reward expectations remains unclear. Previous studies have tended to rely on pre-defined partitioning of states encoded by disjunct neuronal groups or sparse topological drives. A more likely scenario is that striatal neurons are involved in the encoding of multiple different states through their spike patterns, and that an appropriate partitioning of an environment is learned on the basis of task constraints, thus minimizing the number of states involved in solving a particular task. Here we show that striatal activity is sufficient to implement a liquid state, an important prerequisite for such a computation, whereby transient patterns of striatal activity are mapped onto the relevant states. We develop a simple small scale model of the striatum which can reproduce key features of the experimentally observed activity of the major cell types of the striatum. We then use the activity of this network as input for the supervised training of four simple linear readouts to learn three different functions on a plane, where the network is stimulated with the spike coded position of the agent. We discover that the network configuration that best reproduces striatal activity statistics lies on the edge of chaos and has good performance on all three tasks, but that in general, the edge of chaos is a poor predictor of network performance.
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Affiliation(s)
- Carlos Toledo-Suárez
- Bernstein Center Freiburg, Albert-Ludwig University of Freiburg Freiburg, Germany ; Faculty of Biology, Albert-Ludwig University of Freiburg Freiburg, Germany ; Department of Computational Biology, School of Computer Science and Communication Stockholm, Sweden
| | - Renato Duarte
- Bernstein Center Freiburg, Albert-Ludwig University of Freiburg Freiburg, Germany ; Faculty of Biology, Albert-Ludwig University of Freiburg Freiburg, Germany ; Institute for Advanced Simulation (IAS-6) and Institute of Neuroscience and Medicine (INM-6), Jülich Research Centre and JARA Jülich, Germany ; Institute of Adaptive and Neural Computation, School of Informatics, University of Edinburgh Edinburgh, UK
| | - Abigail Morrison
- Bernstein Center Freiburg, Albert-Ludwig University of Freiburg Freiburg, Germany ; Faculty of Biology, Albert-Ludwig University of Freiburg Freiburg, Germany ; Institute for Advanced Simulation (IAS-6) and Institute of Neuroscience and Medicine (INM-6), Jülich Research Centre and JARA Jülich, Germany ; Faculty of Psychology, Institute of Cognitive Neuroscience, Ruhr-University Bochum Bochum, Germany
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207
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Beatty JA, Song SC, Wilson CJ. Cell-type-specific resonances shape the responses of striatal neurons to synaptic input. J Neurophysiol 2014; 113:688-700. [PMID: 25411465 DOI: 10.1152/jn.00827.2014] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Neurons respond to synaptic inputs in cell-type-specific ways. Each neuron type may thus respond uniquely to shared patterns of synaptic input. We applied statistically identical barrages of artificial synaptic inputs to four striatal cell types to assess differences in their responses to a realistic input pattern. Each interneuron type fired in phase with a specific input-frequency component. The fast-spiking interneuron fired in relation to the gamma-band (and higher) frequencies, the low-threshold spike interneuron to the beta-band frequencies, and the cholinergic neurons to the delta-band frequencies. Low-threshold spiking and cholinergic interneurons showed input impedance resonances at frequencies matching their spiking resonances. Fast-spiking interneurons showed resonance of input impedance but at lower than gamma frequencies. The spiny projection neuron's frequency preference did not have a fixed frequency but instead tracked its own firing rate. Spiny cells showed no input impedance resonance. Striatal interneurons are each tuned to a specific frequency band corresponding to the major frequency components of local field potentials. Their influence in the circuit may fluctuate along with the contribution of that frequency band to the input. In contrast, spiny neurons may tune to any of the frequency bands by a change in firing rate.
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Affiliation(s)
- Joseph A Beatty
- Department of Biology, University of Texas, San Antonio, Texas
| | - Soomin C Song
- Department of Biology, University of Texas, San Antonio, Texas
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208
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Xie Y, Heida T, Stegenga J, Zhao Y, Moser A, Tronnier V, Feuerstein TJ, Hofmann UG. High-frequency electrical stimulation suppresses cholinergic accumbens interneurons in acute rat brain slices through GABABreceptors. Eur J Neurosci 2014; 40:3653-62. [DOI: 10.1111/ejn.12736] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2014] [Revised: 08/12/2014] [Accepted: 08/25/2014] [Indexed: 12/13/2022]
Affiliation(s)
- Yijing Xie
- Neuroelectronic Systems; Department of Neurosurgery; University Medical Center Freiburg; 79108 Freiburg Germany
- Graduate School for Computing in Medicine and Life Sciences; University of Lübeck; Lübeck Germany
| | - Tjitske Heida
- Biomedical Signals and Systems; University of Twente; Enschede The Netherlands
| | - Jan Stegenga
- Biomedical Signals and Systems; University of Twente; Enschede The Netherlands
| | - Yan Zhao
- Biomedical Signals and Systems; University of Twente; Enschede The Netherlands
| | - Andreas Moser
- Clinic for Neurology; University of Lübeck; Lübeck Germany
| | - Volker Tronnier
- Graduate School for Computing in Medicine and Life Sciences; University of Lübeck; Lübeck Germany
- Clinic for Neurosurgery; University of Lübeck; Lübeck Germany
| | - Thomas J. Feuerstein
- Freiburg Institute for Advanced Studies (FRIAS); University of Freiburg; Freiburg Germany
- Section of Clinical Neuropharmacology; Department of Neurosurgery; University Medical Center Freiburg; Freiburg Germany
| | - Ulrich G. Hofmann
- Neuroelectronic Systems; Department of Neurosurgery; University Medical Center Freiburg; 79108 Freiburg Germany
- Graduate School for Computing in Medicine and Life Sciences; University of Lübeck; Lübeck Germany
- Institute for Signal Processing; University of Lübeck; Lübeck Germany
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209
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Marcott PF, Mamaligas AA, Ford CP. Phasic dopamine release drives rapid activation of striatal D2-receptors. Neuron 2014; 84:164-176. [PMID: 25242218 DOI: 10.1016/j.neuron.2014.08.058] [Citation(s) in RCA: 91] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/28/2014] [Indexed: 01/04/2023]
Abstract
Striatal dopamine transmission underlies numerous goal-directed behaviors. Medium spiny neurons (MSNs) are a major target of dopamine in the striatum. However, as dopamine does not directly evoke a synaptic event in MSNs, the time course of dopamine signaling in these cells remains unclear. To examine how dopamine release activates D2-receptors on MSNs, G protein activated inwardly rectifying potassium (GIRK2; Kir 3.2) channels were virally overexpressed in the striatum, and the resulting outward currents were used as a sensor of D2-receptor activation. Electrical and optogenetic stimulation of dopamine terminals evoked robust D2-receptor inhibitory postsynaptic currents (IPSCs) in GIRK2-expressing MSNs that occurred in under a second. Evoked D2-IPSCs could be driven by repetitive stimulation and were not occluded by background dopamine tone. Together, the results indicate that D2-receptors on MSNs exhibit functional low affinity and suggest that striatal D2-receptors can encode both tonic and phasic dopamine signals.
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Affiliation(s)
- Pamela F Marcott
- Department of Physiology and Biophysics, Case Western Reserve University School of Medicine, Cleveland, OH 44106-4970, USA
| | - Aphroditi A Mamaligas
- Department of Neurosciences, Case Western Reserve University School of Medicine, Cleveland, OH 44106-4970, USA
| | - Christopher P Ford
- Department of Physiology and Biophysics, Case Western Reserve University School of Medicine, Cleveland, OH 44106-4970, USA; Department of Neurosciences, Case Western Reserve University School of Medicine, Cleveland, OH 44106-4970, USA.
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210
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Role of nitric oxide in the regulation of motor function. An overview of behavioral, biochemical and histological studies in animal models. Pharmacol Rep 2014; 65:1043-55. [PMID: 24399702 DOI: 10.1016/s1734-1140(13)71464-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2013] [Revised: 07/27/2013] [Indexed: 12/17/2022]
Abstract
A compelling body of evidence suggests that nitric oxide (NO), a unique gaseous neurotransmitter and neuromodulator plays a key role in the regulation of motor function. Recently, the interest of researchers concentrates on the NO - soluble guanylyl cyclase (sGC) - cyclic GMP (cGMP) signaling pathway in the striatum as a new target for the treatment of Parkinson's disease (PD). The aim of the study is to review the available literature referring to the role of NO in the integration of basal ganglia functions. First, attention has been focused on behavioral effects of NO donors and neuronal nitric oxide synthase (nNOS) inhibitors in the modulation of motor behavior. Then, disturbances in the nitrergic neurotransmission in PD and its 6-OHDA animal model have been presented. Moreover, the most current data demonstrating the contribution of both dopamine and glutamate to the regulation of NO biosynthesis in the striatum have been analyzed. Finally, the role of NO in the tonic and phasic dopamine release as well as in the regulation of striatal output pathways also has been discussed.
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211
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Muñoz-Manchado AB, Foldi C, Szydlowski S, Sjulson L, Farries M, Wilson C, Silberberg G, Hjerling-Leffler J. Novel Striatal GABAergic Interneuron Populations Labeled in the 5HT3a(EGFP) Mouse. Cereb Cortex 2014; 26:96-105. [PMID: 25146369 DOI: 10.1093/cercor/bhu179] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Histological and morphological studies indicate that approximately 5% of striatal neurons are cholinergic or γ-aminobutyric acidergic (GABAergic) interneurons (gINs). However, the number of striatal neurons expressing known interneuron markers is too small to account for the entire interneuron population. We therefore studied the serotonin (5HT) receptor 3a-enhanced green fluorescent protein (5HT3a(EGFP)) mouse, in which we found that a large number of striatal gINs are labeled. Roughly 20% of 5HT3a(EGFP)-positive cells co-express parvalbumin and exhibit fast-spiking (FS) electrophysiological properties. However, the majority of labeled neurons do not overlap with known molecular interneuron markers. Intrinsic electrical properties reveal at least 2 distinct novel subtypes: a late-spiking (LS) neuropeptide-Y (NPY)-negative neurogliaform (NGF) interneuron, and a large heterogeneous population with several features resembling low-threshold-spiking (LTS) interneurons that do not express somatostatin, NPY, or neuronal nitric oxide synthase. Although the 5HT3a(EGFP) NGF and LTS-like interneurons have electrophysiological properties similar to previously described populations, they are pharmacologically distinct. In direct contrast to previously described NPY(+) LTS and NGF cells, LTS-like 5HT3a(EGFP) cells show robust responses to nicotine administration, while the 5HT3a(EGFP) NGF cell type shows little or no response. By constructing a molecular map of the overlap between these novel populations and existing interneuron populations, we are able to reconcile the morphological and molecular estimates of striatal interneuron numbers.
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Affiliation(s)
| | - C Foldi
- Department of Medical Biochemistry and Biophysics
| | - S Szydlowski
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - L Sjulson
- Department of Psychiatry.,Department of Neuroscience and Physiology, NYU Neuroscience Institute, NYU Langone Medical Center, New York, NY, USA
| | - M Farries
- Department of Biology, University of Texas at San Antonio, San Antonio, TX, USA
| | - C Wilson
- Department of Biology, University of Texas at San Antonio, San Antonio, TX, USA
| | - G Silberberg
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
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212
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Ando N, Sugasawa Y, Inoue R, Aosaki T, Miura M, Nishimura K. Effects of the volatile anesthetic sevoflurane on tonic GABA currents in the mouse striatum during postnatal development. Eur J Neurosci 2014; 40:3147-57. [PMID: 25139222 DOI: 10.1111/ejn.12691] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2014] [Revised: 07/04/2014] [Accepted: 07/11/2014] [Indexed: 11/28/2022]
Abstract
The volatile anesthetic sevoflurane, which is widely used in pediatric surgery, has proposed effects on GABAA receptor-mediated extrasynaptic tonic inhibition. In the developing striatum, medium-sized spiny projection neurons have tonic GABA currents, which function in the excitatory/inhibitory balance and maturation of striatal neural circuits. In this study, we examined the effects of sevoflurane on the tonic GABA currents of medium spiny neurons in developing striatal slices. Sevoflurane strongly increased GABAA receptor-mediated tonic conductance at postnatal days 3-35. The antagonist of the GABA transporter-1, 1-[2-[[(diphenylmethylene)imino]oxy]ethyl]-1,2,5,6-tetrahydro-3-pyridinecarboxylic acid hydrochloride further increased tonic GABA conductance during the application of sevoflurane, thereby increasing the total magnitude of tonic currents. Both GABA (5 μM) and 4,5,6,7-tetrahydroisoxazolo[5,4-c]pyridine-3-ol hydrochloride, the δ-subunit-containing GABAA receptor agonist, induced tonic GABA currents in medium spiny neurons but not in cholinergic neurons. However, sevoflurane additively potentiated the tonic GABA currents in both cells. Interestingly, 4,5,6,7-tetrahydroisoxazolo[5,4-c]pyridine-3-ol hydrochloride-sensitive neurons made a large current response to sevoflurane, indicating the contribution of the δ-subunit on sevoflurane-enhanced tonic GABA currents. Our findings suggest that sevoflurane can affect the tone of tonic GABA inhibition in a developing striatal neural network.
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Affiliation(s)
- Nozomi Ando
- Department of Anesthesiology and Pain Management, Juntendo University School of Medicine, Tokyo, Japan; Neurophysiology Research Group, Tokyo Metropolitan Institute of Gerontology, 35-2 Sakae-cho, Itabashi-ku, Tokyo, 173-0015, Japan
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213
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Atallah HE, McCool AD, Howe MW, Graybiel AM. Neurons in the ventral striatum exhibit cell-type-specific representations of outcome during learning. Neuron 2014; 82:1145-56. [PMID: 24908491 DOI: 10.1016/j.neuron.2014.04.021] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/11/2014] [Indexed: 02/04/2023]
Abstract
The ventromedial striatum (VMS) is a node in circuits underpinning both affect and reinforcement learning. The cellular bases of these functions and especially their potential linkages have been unclear. VMS cholinergic interneurons, however, have been singled out as being related both to affect and to reinforcement-based conditioning, raising the possibility that unique aspects of their signaling could account for these functions. Here we show that VMS tonically active neurons (TANs), including putative cholinergic interneurons, generate unique bidirectional outcome responses during reward-based learning, reporting both positive (reward) and negative (reward omission) outcomes when behavioral change is prompted by switches in reinforcement contingencies. VMS output neurons (SPNs), by contrast, are nearly insensitive to switches in reinforcement contingencies, gradually losing outcome signaling while maintaining responses at trial initiation and goal approach. Thus, TANs and SPNs in the VMS provide distinct signals optimized for different aspects of the learning process.
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Affiliation(s)
- Hisham E Atallah
- McGovern Institute for Brain Research and Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Andrew D McCool
- McGovern Institute for Brain Research and Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Mark W Howe
- McGovern Institute for Brain Research and Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Ann M Graybiel
- McGovern Institute for Brain Research and Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
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214
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Calabresi P, Picconi B, Tozzi A, Ghiglieri V, Di Filippo M. Direct and indirect pathways of basal ganglia: a critical reappraisal. Nat Neurosci 2014; 17:1022-30. [DOI: 10.1038/nn.3743] [Citation(s) in RCA: 474] [Impact Index Per Article: 47.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2014] [Accepted: 05/21/2014] [Indexed: 12/12/2022]
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215
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Petryszyn S, Beaulieu JM, Parent A, Parent M. Distribution and morphological characteristics of striatal interneurons expressing calretinin in mice: a comparison with human and nonhuman primates. J Chem Neuroanat 2014; 59-60:51-61. [PMID: 24960462 DOI: 10.1016/j.jchemneu.2014.06.002] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2014] [Revised: 06/11/2014] [Accepted: 06/12/2014] [Indexed: 10/25/2022]
Abstract
Striatal interneurons display a morphological and chemical heterogeneity that has been particularly well characterized in rats, monkeys and humans. By comparison much less is known of striatal interneurons in mice, although these animals are now widely used as transgenic models of various neurodegenerative diseases. The present immunohistochemical study aimed at characterizing striatal interneurons expressing calretinin (CR) in mice compared to those in squirrel monkeys and humans. The mouse striatum contains both small (9-12 μm) and medium-sized (15-20 μm) CR+ cells. The small cells are intensely stained with a single, slightly varicose and moderately arborized process. They occur throughout the striatum (77±9 cells/mm(3)), but prevail in the area of the subventricular zone and subcallosal streak, with statistically significant anteroposterior and dorsoventral decreasing gradients. The medium-sized cells are less intensely immunoreactive and possess 2-3 long, slightly varicose and poorly branched dendrites. They are rather uniformly scattered throughout the striatum and three times more numerous (224±31 cells/mm(3)) than the smaller CR+ cells. Double immunostaining experiments with choline acetyltransferase (ChAT) as a cholinergic marker in normal and Drd1a-tdTomato/Drd2-EGFP double transgenic mice reveal that none of the small or medium-sized CR+ cells express ChAT or D1 and D2 dopamine receptors. In contrast, the striatum in human and nonhuman primates harbors small and medium-sized CR+/ChAT- cells, as well as large CR+/ChAT+ interneurons that are absent in mice. Such a difference between rodents and primates must be taken into consideration if one hopes to better understand the striatal function in normal and pathological conditions.
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Affiliation(s)
- Sarah Petryszyn
- Department of Psychiatry and Neuroscience, Faculty of Medicine, Université Laval, Quebec City, Quebec, Canada
| | - Jean-Martin Beaulieu
- Department of Psychiatry and Neuroscience, Faculty of Medicine, Université Laval, Quebec City, Quebec, Canada
| | - André Parent
- Department of Psychiatry and Neuroscience, Faculty of Medicine, Université Laval, Quebec City, Quebec, Canada
| | - Martin Parent
- Department of Psychiatry and Neuroscience, Faculty of Medicine, Université Laval, Quebec City, Quebec, Canada.
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216
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Chartoff EH, Connery HS. It's MORe exciting than mu: crosstalk between mu opioid receptors and glutamatergic transmission in the mesolimbic dopamine system. Front Pharmacol 2014; 5:116. [PMID: 24904419 PMCID: PMC4034717 DOI: 10.3389/fphar.2014.00116] [Citation(s) in RCA: 92] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2014] [Accepted: 04/30/2014] [Indexed: 12/15/2022] Open
Abstract
Opioids selective for the G protein-coupled mu opioid receptor (MOR) produce potent analgesia and euphoria. Heroin, a synthetic opioid, is considered one of the most addictive substances, and the recent exponential rise in opioid addiction and overdose deaths has made treatment development a national public health priority. Existing medications (methadone, buprenorphine, and naltrexone), when combined with psychosocial therapies, have proven efficacy in reducing aspects of opioid addiction. Unfortunately, these medications have critical limitations including those associated with opioid agonist therapies (e.g., sustained physiological dependence and opioid withdrawal leading to high relapse rates upon discontinuation), non-adherence to daily dosing, and non-renewal of monthly injection with extended-release naltrexone. Furthermore, current medications fail to ameliorate key aspects of addiction such as powerful conditioned associations that trigger relapse (e.g., cues, stress, the drug itself). Thus, there is a need for developing novel treatments that target neural processes corrupted with chronic opioid use. This requires a basic understanding of molecular and cellular mechanisms underlying effects of opioids on synaptic transmission and plasticity within reward-related neural circuits. The focus of this review is to discuss how crosstalk between MOR-associated G protein signaling and glutamatergic neurotransmission leads to immediate and long-term effects on emotional states (e.g., euphoria, depression) and motivated behavior (e.g., drug-seeking, relapse). Our goal is to integrate findings on how opioids modulate synaptic release of glutamate and postsynaptic transmission via α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid and N-methyl-D-aspartate receptors in the nucleus accumbens and ventral tegmental area with the clinical (neurobehavioral) progression of opioid dependence, as well as to identify gaps in knowledge that can be addressed in future studies.
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Affiliation(s)
- Elena H Chartoff
- Department of Psychiatry, Harvard Medical School, McLean Hospital Belmont, MA, USA
| | - Hilary S Connery
- Department of Psychiatry, Harvard Medical School, McLean Hospital Belmont, MA, USA
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217
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Abstract
The methyl-DNA binding protein MeCP2 is emerging as an important regulator of drug reinforcement processes. Psychostimulants induce phosphorylation of MeCP2 at Ser421; however, the functional significance of this posttranslational modification for addictive-like behaviors was unknown. Here we show that MeCP2 Ser421Ala knock-in mice display both a reduced threshold for the induction of locomotor sensitization by investigator-administered amphetamine and enhanced behavioral sensitivity to the reinforcing properties of self-administered cocaine. These behavioral differences were accompanied in the knock-in mice by changes in medium spiny neuron intrinsic excitability and nucleus accumbens gene expression typically observed in association with repeated exposure to these drugs. These data show that phosphorylation of MeCP2 at Ser421 functions to limit the circuit plasticities in the nucleus accumbens that underlie addictive-like behaviors.
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218
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Neuropathological findings in chorea-acanthocytosis: new insights into mechanisms underlying parkinsonism and seizures. Acta Neuropathol 2014; 127:613-5. [PMID: 24394886 DOI: 10.1007/s00401-013-1241-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2013] [Revised: 12/23/2013] [Accepted: 12/24/2013] [Indexed: 10/25/2022]
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219
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Musella A, Sepman H, Mandolesi G, Gentile A, Fresegna D, Haji N, Conrad A, Lutz B, Maccarrone M, Centonze D. Pre- and postsynaptic type-1 cannabinoid receptors control the alterations of glutamate transmission in experimental autoimmune encephalomyelitis. Neuropharmacology 2014; 79:567-72. [DOI: 10.1016/j.neuropharm.2014.01.007] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2013] [Revised: 01/02/2014] [Accepted: 01/06/2014] [Indexed: 12/31/2022]
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220
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Aquili L, Liu AW, Shindou M, Shindou T, Wickens JR. Behavioral flexibility is increased by optogenetic inhibition of neurons in the nucleus accumbens shell during specific time segments. Learn Mem 2014; 21:223-31. [PMID: 24639489 PMCID: PMC3966536 DOI: 10.1101/lm.034199.113] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
Abstract
Behavioral flexibility is vital for survival in an environment of changing contingencies. The nucleus accumbens may play an important role in behavioral flexibility, representing learned stimulus–reward associations in neural activity during response selection and learning from results. To investigate the role of nucleus accumbens neural activity in behavioral flexibility, we used light-activated halorhodopsin to inhibit nucleus accumbens shell neurons during specific time segments of a bar-pressing task requiring a win–stay/lose–shift strategy. We found that optogenetic inhibition during action selection in the time segment preceding a lever press had no effect on performance. However, inhibition occurring in the time segment during feedback of results—whether rewards or nonrewards—reduced the errors that occurred after a change in contingency. Our results demonstrate critical time segments during which nucleus accumbens shell neurons integrate feedback into subsequent responses. Inhibiting nucleus accumbens shell neurons in these time segments, during reinforced performance or after a change in contingencies, increases lose–shift behavior. We propose that the activity of nucleus shell accumbens shell neurons in these time segments plays a key role in integrating knowledge of results into subsequent behavior, as well as in modulating lose–shift behavior when contingencies change.
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Affiliation(s)
- Luca Aquili
- Okinawa Institute of Science and Technology Graduate University, Neurobiology Research Unit, Onna-son, Japan 904-0495
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221
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Methamphetamine causes degeneration of dopamine cell bodies and terminals of the nigrostriatal pathway evidenced by silver staining. Neuropsychopharmacology 2014; 39:1066-80. [PMID: 24169803 PMCID: PMC3957101 DOI: 10.1038/npp.2013.307] [Citation(s) in RCA: 115] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2013] [Revised: 10/21/2013] [Accepted: 10/22/2013] [Indexed: 12/19/2022]
Abstract
Methamphetamine is a widely abused illicit drug. Recent epidemiological studies showed that methamphetamine increases the risk for developing Parkinson's disease (PD) in agreement with animal studies showing dopaminergic neurotoxicity. We examined the effect of repeated low and medium doses vs single high dose of methamphetamine on degeneration of dopaminergic terminals and cell bodies. Mice were given methamphetamine in one of the following paradigms: three injections of 5 or 10 mg/kg at 3 h intervals or a single 30 mg/kg injection. The integrity of dopaminergic fibers and cell bodies was assessed at different time points after methamphetamine by tyrosine hydroxylase immunohistochemistry and silver staining. The 3 × 10 protocol yielded the highest loss of striatal dopaminergic terminals, followed by the 3 × 5 and 1 × 30. Some degenerating axons could be followed from the striatum to the substantia nigra pars compacta (SNpc). All protocols induced similar significant degeneration of dopaminergic neurons in the SNpc, evidenced by amino-cupric-silver-stained dopaminergic neurons. These neurons died by necrosis and apoptosis. Methamphetamine also killed striatal neurons. By using D1-Tmt/D2-GFP BAC transgenic mice, we observed that degenerating striatal neurons were equally distributed between direct and indirect medium spiny neurons. Despite the reduced number of dopaminergic neurons in the SNpc at 30 days after treatment, there was a partial time-dependent recovery of dopamine terminals beginning 3 days after treatment. Locomotor activity and motor coordination were robustly decreased 1-3 days after treatment, but recovered at later times along with dopaminergic terminals. These data provide direct evidence that methamphetamine causes long-lasting loss/degeneration of dopaminergic cell bodies in the SNpc, along with destruction of dopaminergic terminals in the striatum.
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222
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Dautan D, Huerta-Ocampo I, Witten IB, Deisseroth K, Bolam JP, Gerdjikov T, Mena-Segovia J. A major external source of cholinergic innervation of the striatum and nucleus accumbens originates in the brainstem. J Neurosci 2014; 34:4509-18. [PMID: 24671996 PMCID: PMC3965779 DOI: 10.1523/jneurosci.5071-13.2014] [Citation(s) in RCA: 245] [Impact Index Per Article: 24.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2013] [Revised: 01/24/2014] [Accepted: 02/15/2014] [Indexed: 02/01/2023] Open
Abstract
Cholinergic transmission in the striatal complex is critical for the modulation of the activity of local microcircuits and dopamine release. Release of acetylcholine has been considered to originate exclusively from a subtype of striatal interneuron that provides widespread innervation of the striatum. Cholinergic neurons of the pedunculopontine (PPN) and laterodorsal tegmental (LDT) nuclei indirectly influence the activity of the dorsal striatum and nucleus accumbens through their innervation of dopamine and thalamic neurons, which in turn converge at the same striatal levels. Here we show that cholinergic neurons in the brainstem also provide a direct innervation of the striatal complex. By the expression of fluorescent proteins in choline acetyltransferase (ChAT)::Cre(+) transgenic rats, we selectively labeled cholinergic neurons in the rostral PPN, caudal PPN, and LDT. We show that cholinergic neurons topographically innervate wide areas of the striatal complex: rostral PPN preferentially innervates the dorsolateral striatum, and LDT preferentially innervates the medial striatum and nucleus accumbens core in which they principally form asymmetric synapses. Retrograde labeling combined with immunohistochemistry in wild-type rats confirmed the topography and cholinergic nature of the projection. Furthermore, transynaptic gene activation and conventional double retrograde labeling suggest that LDT neurons that innervate the nucleus accumbens also send collaterals to the thalamus and the dopaminergic midbrain, thus providing both direct and indirect projections, to the striatal complex. The differential activity of cholinergic interneurons and cholinergic neurons of the brainstem during reward-related paradigms suggest that the two systems play different but complementary roles in the processing of information in the striatum.
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Affiliation(s)
- Daniel Dautan
- Medical Research Council Anatomical Neuropharmacology Unit, Department of Pharmacology, University of Oxford, Oxford OX1 3TH, United Kingdom
- School of Psychology, University of Leicester, Leicester LE1 9HN, United Kingdom
| | - Icnelia Huerta-Ocampo
- Medical Research Council Anatomical Neuropharmacology Unit, Department of Pharmacology, University of Oxford, Oxford OX1 3TH, United Kingdom
| | - Ilana B. Witten
- Princeton Neuroscience Institute, Princeton New Jersey 08540, and
| | - Karl Deisseroth
- Department of Psychiatry, Stanford University, Stanford, California 94305
| | - J. Paul Bolam
- Medical Research Council Anatomical Neuropharmacology Unit, Department of Pharmacology, University of Oxford, Oxford OX1 3TH, United Kingdom
| | - Todor Gerdjikov
- School of Psychology, University of Leicester, Leicester LE1 9HN, United Kingdom
| | - Juan Mena-Segovia
- Medical Research Council Anatomical Neuropharmacology Unit, Department of Pharmacology, University of Oxford, Oxford OX1 3TH, United Kingdom
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223
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Tonic inhibition of accumbal spiny neurons by extrasynaptic α4βδ GABAA receptors modulates the actions of psychostimulants. J Neurosci 2014; 34:823-38. [PMID: 24431441 DOI: 10.1523/jneurosci.3232-13.2014] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Within the nucleus accumbens (NAc), synaptic GABAA receptors (GABAARs) mediate phasic inhibition of medium spiny neurons (MSNs) and influence behavioral responses to cocaine. We demonstrate that both dopamine D1- and D2-receptor-expressing MSNs (D-MSNs) additionally harbor extrasynaptic GABAARs incorporating α4, β, and δ subunits that mediate tonic inhibition, thereby influencing neuronal excitability. Both the selective δ-GABAAR agonist THIP and DS2, a selective positive allosteric modulator, greatly increased the tonic current of all MSNs from wild-type (WT), but not from δ(-/-) or α4(-/-) mice. Coupling dopamine and tonic inhibition, the acute activation of D1 receptors (by a selective agonist or indirectly by amphetamine) greatly enhanced tonic inhibition in D1-MSNs but not D2-MSNs. In contrast, prolonged D2 receptor activation modestly reduced the tonic conductance of D2-MSNs. Behaviorally, WT and constitutive α4(-/-) mice did not differ in their expression of cocaine-conditioned place preference (CPP). Importantly, however, mice with the α4 deletion specific to D1-expressing neurons (α4(D1-/-)) showed increased CPP. Furthermore, THIP administered systemically or directly into the NAc of WT, but not α4(-/-) or α4(D1-/-) mice, blocked cocaine enhancement of CPP. In comparison, α4(D2-/-) mice exhibited normal CPP, but no cocaine enhancement. In conclusion, dopamine modulation of GABAergic tonic inhibition of D1- and D2-MSNs provides an intrinsic mechanism to differentially affect their excitability in response to psychostimulants and thereby influence their ability to potentiate conditioned reward. Therefore, α4βδ GABAARs may represent a viable target for the development of novel therapeutics to better understand and influence addictive behaviors.
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224
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δ-opioid and dopaminergic processes in accumbens shell modulate the cholinergic control of predictive learning and choice. J Neurosci 2014; 34:1358-69. [PMID: 24453326 DOI: 10.1523/jneurosci.4592-13.2014] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Decision-making depends on the ability to extract predictive information from the environment to guide future actions. Outcome-specific Pavlovian-instrumental transfer (PIT) provides an animal model of this process in which a stimulus predicting a particular outcome biases choice toward actions earning that outcome. Recent evidence suggests that cellular adaptations of δ-opioid receptors (DORs) on cholinergic interneurons (CINs) in the nucleus accumbens shell (NAc-S) are necessary for PIT. Here we found that modulation of DORs in CINs critically influences D1-receptor (D1R)-expressing projection neurons in the NAc-S to promote PIT. First, we assessed PIT-induced changes in signaling processes in dopamine D1- and D2-receptor-expressing neurons using drd2-eGFP mice, and found that PIT-related signaling was restricted to non-D2R-eGFP-expressing neurons, suggesting major involvement of D1R-neurons. Next we confirmed the role of D1Rs pharmacologically: the D1R antagonist SCH-23390, but not the D2R antagonist raclopride, infused into the NAc-S abolished PIT in rats, an effect that depended on DOR activity. Moreover, asymmetrical infusion of SCH-23390 and the DOR antagonist naltrindole into the NAc-S also abolished PIT. DOR agonists were found to sensitize the firing responses of CINs in brain slices prepared immediately after the PIT test. We confirmed the opioid-acetylcholinergic influence over D1R-neurons by selectively blocking muscarinic M4 receptors in the NAc-S, which tightly regulate the activity of D1Rs, a treatment that rescued the deficit in PIT induced by naltrindole. We describe a model of NAc-S function in which DORs modulate CINs to influence both D1R-neurons and stimulus-guided choice between goal-directed actions.
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225
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Hubert GW, Muly EC. Distribution of AMPA receptor subunit glur1 in the bed nucleus of the stria terminalis and effect of stress. Synapse 2014; 68:194-201. [PMID: 24492926 DOI: 10.1002/syn.21729] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2013] [Accepted: 12/21/2013] [Indexed: 12/11/2022]
Abstract
The brain circuitry thought to be involved in stress responses includes several nuclei of the extended amygdala. The bed nucleus of the stria terminalis (BNST) is thought to be involved in the generation of sustained, nonspecific anxiety. Previous behavioral and electrophysiological experiments demonstrate that glutamate systems are involved in anxiety-like behaviors in the BNST. Antagonists for AMPA receptors injected into the BNST decrease anxiety-like behaviors. However, little is known about the role of AMPA receptors and the mechanism by which they act in the establishment of anxiety-like behavior in response to a stressor. We hypothesized that the distribution of AMPA receptors is changed following a paradigm of unpredictable footshock as has been seen in the basolateral amygdala (BLA). We examined the subcellular localization of the GluR1 subunits of the AMPA receptor. We found that the neuropil of the BNST had a lower density of dendritic spines compared to dendritic shafts in the BLA. The majority of elements immunolabeled for GluR1 were dendritic shafts and spines with axonal and glial elements rarely labeled. Compared with controls, no significant effect was observed on days 1, 6, or 14 poststress. However, there was a trend for an increase at 6 and 14 days poststress. These data demonstrate that GluR1 subunits are primarily located on postsynaptic elements in the BNST. Moreover, it was shown that the response of the AMPA GluR1 subunit does not undergo a significant migration into spines from dendrites in response to a stressor as has been demonstrated in the BLA.
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Affiliation(s)
- George W Hubert
- Department of Psychiatry, Atlanta Veteran's Medical Center, Atlanta, Georgia
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226
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Uthayathas S, Masilamoni GJ, Shaffer CL, Schmidt CJ, Menniti FS, Papa SM. Phosphodiesterase 10A inhibitor MP-10 effects in primates: comparison with risperidone and mechanistic implications. Neuropharmacology 2014; 77:257-67. [PMID: 24490227 PMCID: PMC3934827 DOI: 10.1016/j.neuropharm.2013.10.015] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Phosphodiesterase 10A (PDE10A) is highly expressed in striatal medium spiny neurons of both the direct and indirect output pathways. Similar to dopamine D₂ receptor antagonists acting on indirect pathway neurons, PDE10A inhibitors have shown behavioral effects in rodent models that predict antipsychotic efficacy. These findings have supported the clinical investigation of PDE10A inhibitors as a new treatment for schizophrenia. However, PDE10A inhibitors and D₂ antagonists differ in effects on direct pathway and other neurons of the basal ganglia, indicating that these two drug classes may have divergent antipsychotic efficacy and side effect profile. In the present study, we compare the behavioral effects of the selective PDE10A inhibitor MP-10 to those of the clinical standard D₂ antagonist risperidone in rhesus monkeys using a standardized motor disability scale for parkinsonian primates and a newly designed "Drug Effects on Nervous System" scale to assess non-motor effects. Behavioral effects of MP-10 correlated with its plasma levels and its regulation of metabolic activity in striatal and cortical regions as measured by FDG-PET imaging. While MP-10 and risperidone broadly impacted similar behavioral domains in the primate, their effects had a different underlying basis. MP-10-treated animals retained the ability to respond but did not engage tasks, whereas risperidone-treated animals retained the motivation to respond but were unable to perform the intended actions. These findings are discussed in light of what is currently known about the modulation of striatal circuitry by these two classes of compounds, and provide insight into interpreting emerging clinical data with PDE10A inhibitors for the treatment of psychotic symptoms.
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Affiliation(s)
- Subramaniam Uthayathas
- Division of Neuropharmacology and Neurologic Diseases, Yerkes National Primate Research Center, Emory University, Atlanta, GA
| | - Gunasingh J. Masilamoni
- Division of Neuropharmacology and Neurologic Diseases, Yerkes National Primate Research Center, Emory University, Atlanta, GA
| | - Christopher L. Shaffer
- Department of Pharmacokinetics, Pharmacodynamics and Metabolism, Worldwide Research and Development, Pfizer Inc., Cambridge, MA
| | - Christopher J. Schmidt
- Neuroscience Research Unit, Worldwide Research and Development, Pfizer Inc., Cambridge, MA
| | | | - Stella M. Papa
- Division of Neuropharmacology and Neurologic Diseases, Yerkes National Primate Research Center, Emory University, Atlanta, GA
- Department of Neurology, Emory University, Atlanta, GA
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227
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Allen JL, Liu X, Weston D, Conrad K, Oberdörster G, Cory-Slechta DA. Consequences of developmental exposure to concentrated ambient ultrafine particle air pollution combined with the adult paraquat and maneb model of the Parkinson's disease phenotype in male mice. Neurotoxicology 2014; 41:80-8. [PMID: 24486957 DOI: 10.1016/j.neuro.2014.01.004] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2013] [Revised: 01/20/2014] [Accepted: 01/21/2014] [Indexed: 10/25/2022]
Abstract
Current evidence suggests suceptibility of both the substantia nigra and striatum to exposure to components of air pollution. Further, air pollution has been associated with increased risk of PD diagnsosis in humans or PD-like pathology in animals. This study examined whether exposure of mice to concentrated ambient ultrafine particles (CAPS; <100nm diameter) during the first two weeks of life would alter susceptibility to induction of the Parkinson's disease phenyotype (PDP) in a pesticide-based paraquat and maneb (PQ+MB) model during adulthood utilizing i.p. injections of 10mg/kg PQ and 30mg/kg MB 2× per week for 6 weeks. Evidence of CAPS-induced enhancement of the PQ+MB PDP was limited primarily to delayed recovery of locomotor activity 24 post-injection of PQ+MB that could be related to alterations in striatal GABA inhibitory function. Absence of more extensive interactions might also reflect the finding that CAPS and PQ+MB appeared to differentially target the nigrostriatal dopamine and amino acid systems, with CAPS impacting striatum and PQ+MB impacting dopamine-glutamate function in midbrain; both CAPS and PQ+MB elevated glutamate levels in these specific regions, consistent with potential excitotoxicity. These findings demonstrate the ability of postnatal CAPS to produce locomotor dysfunction and dopaminergic and glutamateric changes, independent of PQ+MB, in brain regions involved in the PDP.
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Affiliation(s)
- Joshua L Allen
- Department of Environmental Medicine, University of Rochester School of Medicine, Rochester, NY 14642, USA.
| | - Xiufang Liu
- Department of Environmental Medicine, University of Rochester School of Medicine, Rochester, NY 14642, USA.
| | - Douglas Weston
- Department of Environmental Medicine, University of Rochester School of Medicine, Rochester, NY 14642, USA.
| | - Katherine Conrad
- Department of Environmental Medicine, University of Rochester School of Medicine, Rochester, NY 14642, USA.
| | - Günter Oberdörster
- Department of Environmental Medicine, University of Rochester School of Medicine, Rochester, NY 14642, USA.
| | - Deborah A Cory-Slechta
- Department of Environmental Medicine, University of Rochester School of Medicine, Rochester, NY 14642, USA.
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228
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GABAergic synaptic transmission onto striatal cholinergic interneurons in dopamine D2 receptor knock-out mice. Neuroscience 2014; 263:138-47. [PMID: 24434772 DOI: 10.1016/j.neuroscience.2014.01.010] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2013] [Revised: 01/04/2014] [Accepted: 01/06/2014] [Indexed: 11/22/2022]
Abstract
Whole-cell or cell-attached analysis was carried out in dopamine (DA) D2 receptor (D2R) knock-out (KO) mice to elucidate the function of this receptor in the regulation of GABAergic synaptic transmission onto striatal cholinergic interneurons as well as their spontaneous firing. In slice preparation obtained from wild-type mice, evoked GABAergic inhibitory postsynaptic currents (IPSCs) showed frequency-dependent suppression, and this suppression significantly decreased in the presence of a D2-like receptor antagonist or in D2R KO mice. Contribution of N-type calcium channel was also significantly reduced in the striatal cholinergic interneurons of the D2R KO mice compared with that in the wild-type mice. Spontaneous firing of striatal cholinergic interneurons was inhibited by 5- or 10-Hz stimulation, and the suppression was decreased in the presence of a D2-like receptor antagonist or in D2R KO mice. These findings substantiate the physiological role of D2R in the regulation of GABAergic synaptic transmission onto striatal cholinergic interneurons as well as their excitability, confirming the tight coupling between D2R and N-type calcium channels in the regulation of GABA release.
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229
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Abstract
This chapter focuses on neurodevelopmental diseases that are tightly linked to abnormal function of the striatum and connected structures. We begin with an overview of three representative diseases in which striatal dysfunction plays a key role--Tourette syndrome and obsessive-compulsive disorder, Rett's syndrome, and primary dystonia. These diseases highlight distinct etiologies that disrupt striatal integrity and function during development, and showcase the varied clinical manifestations of striatal dysfunction. We then review striatal organization and function, including evidence for striatal roles in online motor control/action selection, reinforcement learning, habit formation, and action sequencing. A key barrier to progress has been the relative lack of animal models of these diseases, though recently there has been considerable progress. We review these efforts, including their relative merits providing insight into disease pathogenesis, disease symptomatology, and basal ganglia function.
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230
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Morphological Diversity of GABAergic and Cholinergic Interneurons in the Striatal Dorsolateral and Ventromedial Regions of Rats. Cell Mol Neurobiol 2013; 34:351-9. [DOI: 10.1007/s10571-013-0019-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2013] [Accepted: 12/09/2013] [Indexed: 10/25/2022]
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231
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Cox CJ, Sharma M, Leckman JF, Zuccolo J, Zuccolo A, Kovoor A, Swedo SE, Cunningham MW. Brain human monoclonal autoantibody from sydenham chorea targets dopaminergic neurons in transgenic mice and signals dopamine D2 receptor: implications in human disease. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2013; 191:5524-41. [PMID: 24184556 PMCID: PMC3848617 DOI: 10.4049/jimmunol.1102592] [Citation(s) in RCA: 93] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
How autoantibodies target the brain and lead to disease in disorders such as Sydenham chorea (SC) is not known. SC is characterized by autoantibodies against the brain and is the main neurologic manifestation of streptococcal-induced rheumatic fever. Previously, our novel SC-derived mAb 24.3.1 was found to recognize streptococcal and brain Ags. To investigate in vivo targets of human mAb 24.3.1, VH/VL genes were expressed in B cells of transgenic (Tg) mice as functional chimeric human VH 24.3.1-mouse C-region IgG1(a) autoantibody. Chimeric human-mouse IgG1(a) autoantibody colocalized with tyrosine hydroxylase in the basal ganglia within dopaminergic neurons in vivo in VH 24.3.1 Tg mice. Both human mAb 24.3.1 and IgG1(a) in Tg sera were found to react with human dopamine D2 receptor (D2R). Reactivity of chorea-derived mAb 24.3.1 or SC IgG with D2R was confirmed by dose-dependent inhibitory signaling of D2R as a potential consequence of targeting dopaminergic neurons, reaction with surface-exposed FLAG epitope-tagged D2R, and blocking of Ab reactivity by an extracellular D2R peptide. IgG from SC and a related subset of streptococcal-associated behavioral disorders called "pediatric autoimmune neuropsychiatric disorder associated with streptococci" (PANDAS) with small choreiform movements reacted in ELISA with D2R. Reaction with FLAG-tagged D2R distinguished SC from PANDAS, whereas sera from both SC and PANDAS induced inhibitory signaling of D2R on transfected cells comparably to dopamine. In this study, we define a mechanism by which the brain may be altered by Ab in movement and behavioral disorders.
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Affiliation(s)
- Carol J. Cox
- Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Biomedical Research Center, Oklahoma City, OK 73104
| | - Meenakshi Sharma
- Department of Biomedical and Pharmacological Sciences, College of Pharmacy, University of Rhode Island, Kingston, RI 02881
| | - James F. Leckman
- Yale Child Study Center and Departments of Pediatrics and Psychiatry, Yale University School of Medicine, New Haven, CT 06519
| | - Jonathan Zuccolo
- Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Biomedical Research Center, Oklahoma City, OK 73104
| | - Amir Zuccolo
- Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Biomedical Research Center, Oklahoma City, OK 73104
| | - Abraham Kovoor
- Department of Biomedical and Pharmacological Sciences, College of Pharmacy, University of Rhode Island, Kingston, RI 02881
| | - Susan E. Swedo
- Pediatrics and Developmental Neuroscience Branch, National Institute of Mental Health, Department of Health and Human Services, Bethesda, MD 20892
| | - Madeleine W. Cunningham
- Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Biomedical Research Center, Oklahoma City, OK 73104
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Simmons DA, Belichenko NP, Yang T, Condon C, Monbureau M, Shamloo M, Jing D, Massa SM, Longo FM. A small molecule TrkB ligand reduces motor impairment and neuropathology in R6/2 and BACHD mouse models of Huntington's disease. J Neurosci 2013; 33:18712-27. [PMID: 24285878 PMCID: PMC3841443 DOI: 10.1523/jneurosci.1310-13.2013] [Citation(s) in RCA: 106] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2013] [Revised: 09/09/2013] [Accepted: 10/12/2013] [Indexed: 02/08/2023] Open
Abstract
Loss of neurotrophic support in the striatum caused by reduced brain-derived neurotrophic factor (BDNF) levels plays a critical role in Huntington's disease (HD) pathogenesis. BDNF acts via TrkB and p75 neurotrophin receptors (NTR), and restoring its signaling is a prime target for HD therapeutics. Here we sought to determine whether a small molecule ligand, LM22A-4, specific for TrkB and without effects on p75(NTR), could alleviate HD-related pathology in R6/2 and BACHD mouse models of HD. LM22A-4 was administered to R6/2 mice once daily (5-6 d/week) from 4 to 11 weeks of age via intraperitoneal and intranasal routes simultaneously to maximize brain levels. The ligand reached levels in the R6/2 forebrain greater than the maximal neuroprotective dose in vitro and corrected deficits in activation of striatal TrkB and its key signaling intermediates AKT, PLCγ, and CREB. Ligand-induced TrkB activation was associated with a reduction in HD pathologies in the striatum including decreased DARPP-32 levels, neurite degeneration of parvalbumin-containing interneurons, inflammation, and intranuclear huntingtin aggregates. Aggregates were also reduced in the cortex. Notably, LM22A-4 prevented deficits in dendritic spine density of medium spiny neurons. Moreover, R6/2 mice given LM22A-4 demonstrated improved downward climbing and grip strength compared with those given vehicle, though these groups had comparable rotarod performances and survival times. In BACHD mice, long-term LM22A-4 treatment (6 months) produced similar ameliorative effects. These results support the hypothesis that targeted activation of TrkB inhibits HD-related degenerative mechanisms, including spine loss, and may provide a disease mechanism-directed therapy for HD and other neurodegenerative conditions.
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Affiliation(s)
| | | | - Tao Yang
- Department of Neurology and Neurological Sciences and
| | | | - Marie Monbureau
- Behavioral and Functional Neuroscience Laboratory, Institute for Neuro-Innovation and Translational Neurosciences, Stanford University School of Medicine, Stanford, California 94305
| | - Mehrdad Shamloo
- Behavioral and Functional Neuroscience Laboratory, Institute for Neuro-Innovation and Translational Neurosciences, Stanford University School of Medicine, Stanford, California 94305
| | - Deqiang Jing
- Department of Psychiatry, Weill Cornell Medical College, New York, New York 10021, and
| | - Stephen M. Massa
- Department of Neurology and Laboratory for Computational Neurochemistry and Drug Discovery, Department of Veterans Affairs Medical Center and Department of Neurology, University of California, San Francisco, San Francisco, California 94121
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Learning-related translocation of δ-opioid receptors on ventral striatal cholinergic interneurons mediates choice between goal-directed actions. J Neurosci 2013; 33:16060-71. [PMID: 24107940 DOI: 10.1523/jneurosci.1927-13.2013] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The ability of animals to extract predictive information from the environment to inform their future actions is a critical component of decision-making. This phenomenon is studied in the laboratory using the pavlovian-instrumental transfer protocol in which a stimulus predicting a specific pavlovian outcome biases choice toward those actions earning the predicted outcome. It is well established that this transfer effect is mediated by corticolimbic afferents on the nucleus accumbens shell (NAc-S), and recent evidence suggests that δ-opioid receptors (DORs) play an essential role in this effect. In DOR-eGFP knock-in mice, we show a persistent, learning-related plasticity in the translocation of DORs to the somatic plasma membrane of cholinergic interneurons (CINs) in the NAc-S during the encoding of the specific stimulus-outcome associations essential for pavlovian-instrumental transfer. We found that increased membrane DOR expression reflected both stimulus-based predictions of reward and the degree to which these stimuli biased choice during the pavlovian-instrumental transfer test. Furthermore, this plasticity altered the firing pattern of CINs increasing the variance of action potential activity, an effect that was exaggerated by DOR stimulation. The relationship between the induction of membrane DOR expression in CINs and both pavlovian conditioning and pavlovian-instrumental transfer provides a highly specific function for DOR-related modulation in the NAc-S, and it is consistent with an emerging role for striatal CIN activity in the processing of predictive information. Therefore, our results reveal evidence of a long-term, experience-dependent plasticity in opioid receptor expression on striatal modulatory interneurons critical for the cognitive control of action.
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234
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Ünal B, Shah F, Kothari J, Tepper JM. Anatomical and electrophysiological changes in striatal TH interneurons after loss of the nigrostriatal dopaminergic pathway. Brain Struct Funct 2013; 220:331-49. [PMID: 24173616 DOI: 10.1007/s00429-013-0658-8] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2013] [Accepted: 10/11/2013] [Indexed: 12/15/2022]
Abstract
Using transgenic mice that express enhanced green fluorescent protein (EGFP) under the control of the tyrosine hydroxylase (TH) promoter, we have previously shown that there are approximately 3,000 striatal EGFP-TH interneurons per hemisphere in mice. Here, we report that striatal TH-EGFP interneurons exhibit a small, transient but significant increase in number after unilateral destruction of the nigrostriatal dopaminergic pathway. The increase in cell number is accompanied by electrophysiological and morphological changes. The intrinsic electrophysiological properties of EGFP-TH interneurons ipsilateral to 6-OHDA lesion were similar to those originally reported in intact mice except for a significant reduction in the duration of a characteristic depolarization induced plateau potential. There was a significant change in the distribution of the four previously described electrophysiologically distinct subtypes of striatal TH interneurons. There was a concomitant increase in the frequency of both spontaneous excitatory and inhibitory post-synaptic currents, while their amplitudes did not change. Nigrostriatal lesions did not affect somatic size or dendritic length or branching, but resulted in an increase in the density of proximal dendritic spines and spine-like appendages in EGFP-TH interneurons. The changes indicate that electrophysiology properties and morphology of striatal EGFP-TH interneurons depend on endogenous levels of dopamine arising from the nigrostriatal pathway. Furthermore, these changes may serve to help compensate for the changes in activity of spiny projection neurons that occur following loss of the nigrostriatal innervation in experimental or in early idiopathic Parkinson's disease by increasing feedforward GABAergic inhibition exerted by these interneurons.
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Affiliation(s)
- Bengi Ünal
- Center for Molecular and Behavioral Neuroscience, Aidekman Research Center, Rutgers University, 197 University Avenue, Newark, NJ, 07102, USA
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235
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Barbaresi P, Mensà E, Lariccia V, Pugnaloni A, Amoroso S, Fabri M. Differential distribution of parvalbumin- and calbindin-D28K-immunoreactive neurons in the rat periaqueductal gray matter and their colocalization with enzymes producing nitric oxide. Brain Res Bull 2013; 99:48-62. [PMID: 24107244 DOI: 10.1016/j.brainresbull.2013.09.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2013] [Revised: 09/09/2013] [Accepted: 09/17/2013] [Indexed: 10/26/2022]
Abstract
The distribution, colocalization with enzymes producing nitric oxide (NO), and the synaptic organization of neurons containing two calcium-binding proteins (CaBPs) - parvalbumin (Parv) and calbindin-D28K (Calb) - were investigated in the rat periaqueductal gray matter (PAG). Parv-immunopositive (ParvIP) neurons were detected in the mesencephalic nucleus and rarely in the PAG. CalbIP neurons were found both in the dorsolateral (PAG-dl) and ventrolateral PAG (PAG-vl); their size ranged from 112.96 μm(2) (PAG-dl) to 125.13 μm(2) (PAG-vl). Ultrastructurally Parv and Calb immunoreactivity was mostly found in dendritic profiles. Axon terminals containing each of the two CaBPs formed symmetric synapses. Moreover both Parv and Calb were used to label a subpopulation of NO-producing neurons. Colocalization was investigated using two protocols: (i) a combination of Calb and Parv immunocytochemistry (Icc) with nicotinamide adenine dinucleotide phosphate diaphorase (NADPH-d) histochemistry (Hi) and (ii) neuronal NO synthase-Icc (nNOS) (immunofluorescence). Both techniques demonstrated a complete lack of colocalization of Parv and NADPH-d/nNOS in PAG neurons. Double-labeled (DL) neurons (Calb-NADPH-d; Calb-nNOS) were detected in PAG-dl. NADPH-d-Hi/Calb-Icc indicated that 41-47% of NADPH-d-positive neurons contained Calb, whereas 17-23% of CalbIP cells contained NADPH-d. Two-color immunofluorescence revealed that 53-66% of nNOSIP cells colocalized with Calb and 24-34% of CalbIP neurons contained nNOS. DL neuron size was 104.44 μm(2); neurons labeled only with NADPH-d or Calb measured 89.793 μm(2) and 113.48 μm(2), respectively. Together with previous findings (Barbaresi et al. [2012]) these data suggest that: Therefore the important aspect of the PAG intrinsic organization emerging from this and previous double-labeling studies is the chemical diversity of NO-synthesizing neurons, which is likely related to the different functions in which these neurons are involved.
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Affiliation(s)
- Paolo Barbaresi
- Department of Experimental and Clinical Medicine, Section of Neuroscience and Cell Biology, Marche Polytechnic University, I-60020 Ancona, Italy.
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Reiner A, Shelby E, Wang H, DeMarch Z, Deng Y, Guley NH, Hogg V, Roxburgh R, Tippett LJ, Waldvogel HJ, Faull RLM. Striatal parvalbuminergic neurons are lost in Huntington's disease: implications for dystonia. Mov Disord 2013; 28:1691-9. [PMID: 24014043 PMCID: PMC3812318 DOI: 10.1002/mds.25624] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2013] [Revised: 07/01/2013] [Accepted: 07/03/2013] [Indexed: 12/13/2022] Open
Abstract
Although dystonia represents a major source of motor disability in Huntington's disease (HD), its pathophysiology remains unknown. Because recent animal studies indicate that loss of parvalbuminergic (PARV+) striatal interneurons can cause dystonia, we investigated if loss of PARV+ striatal interneurons occurs during human HD progression, and thus might contribute to dystonia in HD. We used immunolabeling to detect PARV+ interneurons in fixed sections, and corrected for disease-related striatal atrophy by expressing PARV+ interneuron counts in ratio to interneurons co-containing somatostatin and neuropeptide Y (whose numbers are unaffected in HD). At all symptomatic HD grades, PARV+ interneurons were reduced to less than 26% of normal abundance in rostral caudate. In putamen rostral to the level of globus pallidus, loss of PARV+ interneurons was more gradual, not dropping off to less than 20% of control until grade 2. Loss of PARV+ interneurons was even more gradual in motor putamen at globus pallidus levels, with no loss at grade 1, and steady grade-wise decline thereafter. A large decrease in striatal PARV+ interneurons, thus, occurs in HD with advancing disease grade, with regional variation in the loss per grade. Given the findings of animal studies and the grade-wise loss of PARV+ striatal interneurons in motor striatum in parallel with the grade-wise appearance and worsening of dystonia, our results raise the possibility that loss of PARV+ striatal interneurons is a contributor to dystonia in HD.
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Affiliation(s)
- Anton Reiner
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science CenterMemphis, Tennessee, USA
| | - Evan Shelby
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science CenterMemphis, Tennessee, USA
| | - Hongbing Wang
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science CenterMemphis, Tennessee, USA
| | - Zena DeMarch
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science CenterMemphis, Tennessee, USA
| | - Yunping Deng
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science CenterMemphis, Tennessee, USA
| | - Natalie Hart Guley
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science CenterMemphis, Tennessee, USA
| | - Virginia Hogg
- Centre for Brain Research, University of AucklandAuckland, New Zealand
- Department of Psychology, University of AucklandAuckland, New Zealand
| | - Richard Roxburgh
- Centre for Brain Research, University of AucklandAuckland, New Zealand
- Department of Neurology, Auckland City HospitalAuckland, New Zealand
| | - Lynette J Tippett
- Centre for Brain Research, University of AucklandAuckland, New Zealand
- Department of Psychology, University of AucklandAuckland, New Zealand
| | - Henry J Waldvogel
- Centre for Brain Research, University of AucklandAuckland, New Zealand
- Department of Anatomy with Radiology, University of AucklandAuckland, New Zealand
| | - Richard LM Faull
- Centre for Brain Research, University of AucklandAuckland, New Zealand
- Department of Anatomy with Radiology, University of AucklandAuckland, New Zealand
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237
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Yamamoto K, Ebihara K, Koshikawa N, Kobayashi M. Reciprocal regulation of inhibitory synaptic transmission by nicotinic and muscarinic receptors in rat nucleus accumbens shell. J Physiol 2013; 591:5745-63. [PMID: 24018951 DOI: 10.1113/jphysiol.2013.258558] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Medium spiny neurones (MSNs) in the nucleus accumbens (NAc) are the principal neurones whose activities are regulated by GABAergic inputs from MSNs and fast-spiking interneurones (FSNs). Cholinergic interneurones play important roles in the regulation of activity in MSNs; however, how acetylcholine modulates inhibitory synaptic transmission from MSNs/FSNs to MSNs remains unknown. We performed paired whole-cell patch-clamp recordings from MSNs and FSNs in rat NAc shell slice preparations and examined cholinergic effects on unitary inhibitory postsynaptic currents (uIPSCs). Carbachol (1 μM) suppressed uIPSC amplitude by 58.3 ± 8.0% in MSN→MSN connections, accompanied by increases in paired-pulse ratio and failure rate, suggesting that acetylcholine reduces the probability of GABA release from the synaptic terminals of MSNs. Carbachol-induced uIPSC suppression was antagonised by 100 μM atropine, and was mimicked by pilocarpine (1 μM) and acetylcholine (1 μM) but not nicotine (1 μM). Application of AM251 slightly reduced carbachol-induced uIPSC suppression (30.8 ± 8.9%), suggesting an involvement of endocannabinoid signalling in muscarinic suppression of uIPSCs. In contrast, FSN→MSN connections showed that pilocarpine had little effect on the uIPSC amplitude, whereas both nicotine and acetylcholine facilitated uIPSC amplitude, with decreases in failure rate and paired-pulse ratio, suggesting that nicotine-induced uIPSC facilitation is mediated by presynaptic mechanisms. Miniature IPSC recordings support these hypotheses of presynaptic cholinergic mechanisms. These results suggest a differential role for muscarinic and nicotinic receptors in GABA release, which depends on presynaptic neuronal subtypes in the NAc shell.
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Affiliation(s)
- Kiyofumi Yamamoto
- M. Kobayashi: Department of Pharmacology, Nihon University School of Dentistry, 1-8-13 Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8310, Japan.
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238
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Adler A, Katabi S, Finkes I, Prut Y, Bergman H. Different correlation patterns of cholinergic and GABAergic interneurons with striatal projection neurons. Front Syst Neurosci 2013; 7:47. [PMID: 24027501 PMCID: PMC3760072 DOI: 10.3389/fnsys.2013.00047] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2013] [Accepted: 08/15/2013] [Indexed: 11/16/2022] Open
Abstract
The striatum is populated by a single projection neuron group, the medium spiny neurons (MSNs), and several groups of interneurons. Two of the electrophysiologically well-characterized striatal interneuron groups are the tonically active neurons (TANs), which are presumably cholinergic interneurons, and the fast spiking interneurons (FSIs), presumably parvalbumin (PV) expressing GABAergic interneurons. To better understand striatal processing it is thus crucial to define the functional relationship between MSNs and these interneurons in the awake and behaving animal. We used multiple electrodes and standard physiological methods to simultaneously record MSN spiking activity and the activity of TANs or FSIs from monkeys engaged in a classical conditioning paradigm. All three cell populations were highly responsive to the behavioral task. However, they displayed different average response profiles and a different degree of response synchronization (signal correlation). TANs displayed the most transient and synchronized response, MSNs the most diverse and sustained response and FSIs were in between on both parameters. We did not find evidence for direct monosynaptic connectivity between the MSNs and either the TANs or the FSIs. However, while the cross correlation histograms of TAN to MSN pairs were flat, those of FSI to MSN displayed positive asymmetrical broad peaks. The FSI-MSN correlogram profile implies that the spikes of MSNs follow those of FSIs and both are driven by a common, most likely cortical, input. Thus, the two populations of striatal interneurons are probably driven by different afferents and play complementary functional roles in the physiology of the striatal microcircuit.
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Affiliation(s)
- Avital Adler
- Department of Medical Neurobiology, Institute of Medical Research Israel-Canada, The Hebrew University-Hadassah Medical School Jerusalem, Israel ; The Interdisciplinary Center for Neural Computation, The Hebrew University Jerusalem, Israel
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239
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Is there a role for nitric oxide in methamphetamine-induced dopamine terminal degeneration? Neurotox Res 2013; 25:153-60. [PMID: 23918001 DOI: 10.1007/s12640-013-9415-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2013] [Revised: 07/18/2013] [Accepted: 07/23/2013] [Indexed: 12/21/2022]
Abstract
Methamphetamine (METH) abuse results in long-term damage to the dopaminergic system, manifesting as decreases in dopamine (DA) tissue content, DA transporter binding, as well as tyrosine hydroxylase and vesicular monoamine transporter immunostaining. However, the exact cascade of events that ultimately result in this damage has not been clearly elucidated. One factor that has been heavily implicated in METH-induced DA terminal degeneration is the production of nitric oxide (NO). Unfortunately, many of the studies attempting to clarify the role of NO in METH-induced neurotoxicity have been confounded by issues such as the disruption of METH-induced hyperthermia, preventing the formation of strong conclusions. As a result, there is a body of work suggesting that NO is sufficient for METH-induced neurotoxicity, while other studies suggest that NO does not play a role in METH-induced degeneration of DA nerve terminals. This review summarizes the existing studies investigating the role of NO in METH-induced neurotoxicity, and argues that while NO may be necessary for METH-induced neurotoxicity, it is not sufficient. Finally, important areas of future investigation are highlighted and discussed.
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240
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Gonzales KK, Pare JF, Wichmann T, Smith Y. GABAergic inputs from direct and indirect striatal projection neurons onto cholinergic interneurons in the primate putamen. J Comp Neurol 2013; 521:2502-22. [PMID: 23296794 PMCID: PMC3983787 DOI: 10.1002/cne.23295] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2012] [Revised: 11/14/2012] [Accepted: 12/27/2012] [Indexed: 01/30/2023]
Abstract
Striatal cholinergic interneurons (ChIs) are involved in reward-dependent learning and the regulation of attention. The activity of these neurons is modulated by intrinsic and extrinsic γ-aminobutyric acid (GABA)ergic and glutamatergic afferents, but the source and relative prevalence of these diverse regulatory inputs remain to be characterized. To address this issue, we performed a quantitative ultrastructural analysis of the GABAergic and glutamatergic innervation of ChIs in the postcommissural putamen of rhesus monkeys. Postembedding immunogold localization of GABA combined with peroxidase immunostaining for choline acetyltransferase showed that 60% of all synaptic inputs to ChIs originate from GABAergic terminals, whereas 21% are from putatively glutamatergic terminals that establish asymmetric synapses, and 19% from other (non-GABAergic) sources of symmetric synapses. Double pre-embedding immunoelectron microscopy using substance P and Met-/Leu-enkephalin antibodies to label GABAergic terminals from collaterals of "direct" and "indirect" striatal projection neurons, respectively, revealed that 47% of the indirect pathway terminals and 36% of the direct pathway terminals target ChIs. Together, substance P- and enkephalin-positive terminals represent 24% of all synapses onto ChIs in the monkey putamen. These findings show that ChIs receive prominent GABAergic inputs from multiple origins, including a significant contingent from axon collaterals of direct and indirect pathway projection neurons.
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Affiliation(s)
- Kalynda Kari Gonzales
- Yerkes National Primate Research Center, Emory University, Atlanta, Georgia 30329
- Udall Center of Excellence for Parkinson's Disease Research, Emory University, Atlanta, Georgia 30329
| | - Jean-Francois Pare
- Yerkes National Primate Research Center, Emory University, Atlanta, Georgia 30329
- Udall Center of Excellence for Parkinson's Disease Research, Emory University, Atlanta, Georgia 30329
| | - Thomas Wichmann
- Yerkes National Primate Research Center, Emory University, Atlanta, Georgia 30329
- Department of Neurology, Emory University, Atlanta, Georgia 30329
- Udall Center of Excellence for Parkinson's Disease Research, Emory University, Atlanta, Georgia 30329
| | - Yoland Smith
- Yerkes National Primate Research Center, Emory University, Atlanta, Georgia 30329
- Department of Neurology, Emory University, Atlanta, Georgia 30329
- Udall Center of Excellence for Parkinson's Disease Research, Emory University, Atlanta, Georgia 30329
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241
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Villalba RM, Smith Y. Differential striatal spine pathology in Parkinson's disease and cocaine addiction: a key role of dopamine? Neuroscience 2013; 251:2-20. [PMID: 23867772 DOI: 10.1016/j.neuroscience.2013.07.011] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2013] [Accepted: 07/03/2013] [Indexed: 01/19/2023]
Abstract
In the striatum, the dendritic tree of the two main populations of projection neurons, called "medium spiny neurons (MSNs)", are covered with spines that receive glutamatergic inputs from the cerebral cortex and thalamus. In Parkinson's disease (PD), striatal MSNs undergo an important loss of dendritic spines, whereas aberrant overgrowth of striatal spines occurs following chronic cocaine exposure. This review examines the possibility that opposite dopamine dysregulation is one of the key factors that underlies these structural changes. In PD, nigrostriatal dopamine degeneration results in a significant loss of dendritic spines in the dorsal striatum, while rodents chronically exposed to cocaine and other psychostimulants, display an increase in the density of "thin and immature" spines in the nucleus accumbens (NAc). In rodent models of PD, there is evidence that D2 dopamine receptor-containing MSNs are preferentially affected, while D1-positive cells are the main targets of increased spine density in models of addiction. However, such specificity remains to be established in primates. Although the link between the extent of striatal spine changes and the behavioral deficits associated with these disorders remains controversial, there is unequivocal evidence that glutamatergic synaptic transmission is significantly altered in both diseased conditions. Recent studies have suggested that opposite calcium-mediated regulation of the transcription factor myocyte enhancer factor 2 (MEF2) function induces these structural defects. In conclusion, there is strong evidence that dopamine is a major, but not the sole, regulator of striatal spine pathology in PD and addiction to psychostimulants. Further studies of the role of glutamate and other genes associated with spine plasticity in mediating these effects are warranted.
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Affiliation(s)
- R M Villalba
- Yerkes National Primate Research Center, Emory University, 954, Gatewood Road NE, Atlanta, GA 30329, USA; UDALL Center of Excellence for Parkinson's Disease, Emory University, 954, Gatewood Road NE, Atlanta, GA 30329, USA.
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242
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De Chiara V, Motta C, Rossi S, Studer V, Barbieri F, Lauro D, Bernardi G, Centonze D. Interleukin-1β alters the sensitivity of cannabinoid CB1 receptors controlling glutamate transmission in the striatum. Neuroscience 2013; 250:232-9. [PMID: 23856068 DOI: 10.1016/j.neuroscience.2013.06.069] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2013] [Revised: 06/25/2013] [Accepted: 06/26/2013] [Indexed: 01/30/2023]
Abstract
Proinflammatory cytokines such as tumor necrosis factor-α and interleukin-1β (IL1β) regulate both excitatory and inhibitory synaptic transmission in the central nervous system. The interaction between IL1β and endocannabinoid system (ECS) is also emerging, based on the evidence that IL1β effects on striatal spontaneous excitatory and inhibitory postsynaptic currents are regulated by transient receptor potential vanilloid 1 (TRPV1) channels, members of the ECS. Furthermore, IL1β has also been shown to control the sensitivity of cannabinoid CB1 receptors controlling GABA transmission (CB1Rs(GABA)) in the striatum. To better detail the synaptic action of IL1β, and to clarify its complex interaction with the ECS, here we investigated the possible interplay between IL1β and CB1Rs controlling glutamate transmission (CB1Rs(glu)), other critical elements of the ECS. Our results show that the sensitivity of CB1Rs(glu) is fully blocked in the presence of IL1β in corticostriatal brain slices, and that the protein kinase C/TRPV1 pathway is involved in this effect. IL1β failed to modulate the sensitivity of glutamate synapses to the stimulation of GABAB receptors. We also provided evidence that IL1β-CB1Rs(GABA) but not IL1β-CB1Rs(glu) interaction is under the control of the brain-derived neurotrophic factor (BDNF)/trkB signaling and of lipid raft composition, because BDNF gene partial deletion, pharmacological blockade of trkB and membrane cholesterol removal with methyl-β-cyclodextrin all blocked IL1β-mediated inhibition of CB1Rs(GABA) but left unaltered the sensitivity of CB1Rs(glu) to this cytokine. Our results provide further evidence that synaptic transmission and the ECS are regulated by IL1β in the striatum.
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Affiliation(s)
- V De Chiara
- Dipartimento di Medicina dei Sistemi, Università Tor Vergata, Via Montpellier 1, 00133 Rome, Italy; Fondazione Santa Lucia/Centro Europeo per la Ricerca sul Cervello (CERC), Via del Fosso di Fiorano 64, 00143 Rome, Italy
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243
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Synaptic connectivity between rat striatal spiny projection neurons in vivo: Unexpected multiple somatic innervation in the context of overall sparse proximal connectivity. ACTA ACUST UNITED AC 2013. [DOI: 10.1016/j.baga.2013.04.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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244
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Bronfeld M, Israelashvili M, Bar-Gad I. Pharmacological animal models of Tourette syndrome. Neurosci Biobehav Rev 2013; 37:1101-19. [DOI: 10.1016/j.neubiorev.2012.09.010] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2012] [Revised: 08/28/2012] [Accepted: 09/05/2012] [Indexed: 12/22/2022]
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245
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Combinational effects of ketamine and amphetamine on behaviors and neurotransmitter systems of mice. Neurotoxicology 2013; 37:136-43. [DOI: 10.1016/j.neuro.2013.04.014] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2012] [Revised: 04/16/2013] [Accepted: 04/25/2013] [Indexed: 11/19/2022]
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246
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Multiple sources of striatal inhibition are differentially affected in Huntington's disease mouse models. J Neurosci 2013; 33:7393-406. [PMID: 23616545 DOI: 10.1523/jneurosci.2137-12.2013] [Citation(s) in RCA: 90] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
In Huntington's disease (HD) mouse models, spontaneous inhibitory synaptic activity is enhanced in a subpopulation of medium-sized spiny neurons (MSNs), which could dampen striatal output. We examined the potential source(s) of increased inhibition using electrophysiological and optogenetic methods to assess feedback and feedforward inhibition in two transgenic mouse models of HD. Single whole-cell patch-clamp recordings demonstrated that increased GABA synaptic activity impinges principally on indirect pathway MSNs. Dual patch recordings between MSNs demonstrated reduced connectivity between MSNs in HD mice. However, while connectivity was strictly unidirectional in controls, in HD mice bidirectional connectivity occurred. Other sources of increased GABA activity in MSNs also were identified. Dual patch recordings from fast spiking (FS) interneuron-MSN pairs demonstrated greater but variable amplitude responses in MSNs. In agreement, selective optogenetic stimulation of parvalbumin-expressing, FS interneurons induced significantly larger amplitude MSN responses in HD compared with control mice. While there were no differences in responses of MSNs evoked by activating single persistent low-threshold spiking (PLTS) interneurons in recorded pairs, these interneurons fired more action potentials in both HD models, providing another source for increased frequency of spontaneous GABA synaptic activity in MSNs. Selective optogenetic stimulation of somatostatin-expressing, PLTS interneurons did not reveal any significant differences in responses of MSNs in HD mice. These findings provide strong evidence that both feedforward and to a lesser extent feedback inhibition to MSNs in HD can potentially be sources for the increased GABA synaptic activity of indirect pathway MSNs.
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247
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Ferré S, Orrú M, Guitart X. Paraxanthine: Connecting Caffeine to Nitric Oxide Neurotransmission. JOURNAL OF CAFFEINE RESEARCH 2013; 3:72-78. [PMID: 24761277 DOI: 10.1089/jcr.2013.0006] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Recent results obtained in our laboratory indicate that paraxanthine, the main metabolite of caffeine in humans, produces a significantly stronger locomotor activation in rats than caffeine. Furthermore, paraxanthine also produced a very significant increase in striatal extracellular concentrations of dopamine. Searching for an additional mechanism other than adenosine antagonism responsible for these psychostimulant-like effects, it was found that paraxanthine, but not caffeine, inhibited cGMP-preferring phosphodiesterases. Furthermore, interrupting nitric oxide neurotransmision (inhibiting nitric oxide synthase) significantly decreased both the locomotor-activating and the dopamine-releasing effects of paraxanthine. These results open up some obvious questions about the role of paraxanthine in the pharmacological effects of caffeine.
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Affiliation(s)
- Sergi Ferré
- Intramural Research Program, Integrative Neurobiology Section, Department of Health and Human Services, National Institute on Drug Abuse , Baltimore, Maryland
| | - Marco Orrú
- Intramural Research Program, Integrative Neurobiology Section, Department of Health and Human Services, National Institute on Drug Abuse , Baltimore, Maryland
| | - Xavier Guitart
- Intramural Research Program, Integrative Neurobiology Section, Department of Health and Human Services, National Institute on Drug Abuse , Baltimore, Maryland
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248
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Song CH, Bernhard D, Bolarinwa C, Hess EJ, Smith Y, Jinnah HA. Subtle microstructural changes of the striatum in a DYT1 knock-in mouse model of dystonia. Neurobiol Dis 2013; 54:362-71. [PMID: 23336980 PMCID: PMC3628999 DOI: 10.1016/j.nbd.2013.01.008] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2012] [Revised: 01/04/2013] [Accepted: 01/10/2013] [Indexed: 11/21/2022] Open
Abstract
The dystonias are comprised of a group of disorders that share common neurological abnormalities of involuntary twisting or repetitive movements and postures. The most common inherited primary dystonia is DYT1 dystonia, which is due to loss of a GAG codon in the TOR1A gene that encodes torsinA. Autopsy studies of brains from patients with DYT1 dystonia have revealed few abnormalities, although recent neuroimaging studies have implied the existence of microstructural defects that might not be detectable with traditional histopathological methods. The current studies took advantage of a knock-in mouse model for DYT1 dystonia to search for subtle anatomical abnormalities in the striatum, a region often implicated in studies of dystonia. Multiple abnormalities were identified using a combination of quantitative stereological measures of immunohistochemical stains for specific neuronal populations, morphometric studies of Golgi-stained neurons, and immuno-electron microscopy of synaptic connectivity. In keeping with other studies, there was no obvious loss of striatal neurons in the DYT1 mutant mice. However, interneurons immunoreactive for choline acetyltransferase or parvalbumin were larger in the mutants than in control mice. In contrast, interneurons immunoreactive for neuronal nitric oxide synthase were smaller in the mutants than in controls. Golgi histochemical studies of medium spiny projection neurons in the mutant mice revealed slightly fewer and thinner dendrites, and a corresponding loss of dendritic spines. Electron microscopic studies showed a reduction in the ratio of axo-spinous to axo-dendritic synaptic inputs from glutamatergic and dopaminergic sources in mutant mice compared with controls. These results suggest specific anatomical substrates for altered signaling in the striatum and potential correlates of the abnormalities implied by human imaging studies of DYT1 dystonia.
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Affiliation(s)
- Chang-Hyun Song
- Department of Neurology, Emory University, Atlanta GA, 30322
| | | | - Caroline Bolarinwa
- Yerkes National Primate Research Center and Department of Neurology, Emory University, Atlanta GA, 30329
| | - Ellen J. Hess
- Department of Neurology, Emory University, Atlanta GA, 30322
- Department of Pharmacology, Emory University, Atlanta GA, 30322
| | - Yoland Smith
- Yerkes National Primate Research Center and Department of Neurology, Emory University, Atlanta GA, 30329
| | - H. A. Jinnah
- Departments of Neurology, Human Genetics and Pediatrics, Emory University, Atlanta GA 30322
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249
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Separate populations of neurons in ventral striatum encode value and motivation. PLoS One 2013; 8:e64673. [PMID: 23724077 PMCID: PMC3665540 DOI: 10.1371/journal.pone.0064673] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2013] [Accepted: 04/16/2013] [Indexed: 11/19/2022] Open
Abstract
Neurons in the ventral striatum (VS) fire to cues that predict differently valued rewards. It is unclear whether this activity represents the value associated with the expected reward or the level of motivation induced by reward anticipation. To distinguish between the two, we trained rats on a task in which we varied value independently from motivation by manipulating the size of the reward expected on correct trials and the threat of punishment expected upon errors. We found that separate populations of neurons in VS encode expected value and motivation.
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250
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Multiple controls exerted by 5-HT2C receptors upon basal ganglia function: from physiology to pathophysiology. Exp Brain Res 2013; 230:477-511. [PMID: 23615975 DOI: 10.1007/s00221-013-3508-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2013] [Accepted: 03/28/2013] [Indexed: 10/26/2022]
Abstract
Serotonin2C (5-HT2C) receptors are expressed in the basal ganglia, a group of subcortical structures involved in the control of motor behaviour, mood and cognition. These receptors are mediating the effects of 5-HT throughout different brain areas via projections originating from midbrain raphe nuclei. A growing interest has been focusing on the function of 5-HT2C receptors in the basal ganglia because they may be involved in various diseases of basal ganglia function notably those associated with chronic impairment of dopaminergic transmission. 5-HT2C receptors act on numerous types of neurons in the basal ganglia, including dopaminergic, GABAergic, glutamatergic or cholinergic cells. Perhaps inherent to their peculiar molecular properties, the modality of controls exerted by 5-HT2C receptors over these cell populations can be phasic, tonic (dependent on the 5-HT tone) or constitutive (a spontaneous activity without the presence of the ligand). These controls are functionally organized in the basal ganglia: they are mainly localized in the input structures and preferentially distributed in the limbic/associative territories of the basal ganglia. The nature of these controls is modified in neuropsychiatric conditions such as Parkinson's disease, tardive dyskinesia or addiction. Most of the available data indicate that the function of 5-HT2C receptor is enhanced in cases of chronic alterations of dopamine neurotransmission. The review illustrates that 5-HT2C receptors play a role in maintaining continuous controls over the basal ganglia via multiple diverse actions. We will discuss their interest for treatments aimed at ameliorating current pharmacotherapies in schizophrenia, Parkinson's disease or drugs abuse.
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