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Jun S, Ou X, Shi L, Yu H, Deng T, Chen J, Nie X, Hao Y, Shi Y, Liu W, Tian Y, Wang S, Yuan F. Circuit-Specific Control of Blood Pressure by PNMT-Expressing Nucleus Tractus Solitarii Neurons. Neurosci Bull 2023; 39:1193-1209. [PMID: 36588135 PMCID: PMC10387028 DOI: 10.1007/s12264-022-01008-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2022] [Accepted: 10/18/2022] [Indexed: 01/03/2023] Open
Abstract
The nucleus tractus solitarii (NTS) is one of the morphologically and functionally defined centers that engage in the autonomic regulation of cardiovascular activity. Phenotypically-characterized NTS neurons have been implicated in the differential regulation of blood pressure (BP). Here, we investigated whether phenylethanolamine N-methyltransferase (PNMT)-expressing NTS (NTSPNMT) neurons contribute to the control of BP. We demonstrate that photostimulation of NTSPNMT neurons has variable effects on BP. A depressor response was produced during optogenetic stimulation of NTSPNMT neurons projecting to the paraventricular nucleus of the hypothalamus, lateral parabrachial nucleus, and caudal ventrolateral medulla. Conversely, photostimulation of NTSPNMT neurons projecting to the rostral ventrolateral medulla produced a robust pressor response and bradycardia. In addition, genetic ablation of both NTSPNMT neurons and those projecting to the rostral ventrolateral medulla impaired the arterial baroreflex. Overall, we revealed the neuronal phenotype- and circuit-specific mechanisms underlying the contribution of NTSPNMT neurons to the regulation of BP.
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Affiliation(s)
- Shirui Jun
- Department of Neurobiology, Hebei Medical University, Shijiazhuang, 050017, China
| | - Xianhong Ou
- Institute of Cardiovascular Research, Southwest Medical University, Luzhou, 646000, China
| | - Luo Shi
- Department of Neurobiology, Hebei Medical University, Shijiazhuang, 050017, China
| | - Hongxiao Yu
- Department of Neurobiology, Hebei Medical University, Shijiazhuang, 050017, China
| | - Tianjiao Deng
- Department of Neurobiology, Hebei Medical University, Shijiazhuang, 050017, China
| | - Jinting Chen
- Core Facilities and Centers, Institute of Medicine and Health, Hebei Medical University, Shijiazhuang, 050017, China
| | - Xiaojun Nie
- Department of Neurobiology, Hebei Medical University, Shijiazhuang, 050017, China
| | - Yinchao Hao
- Department of Neurobiology, Hebei Medical University, Shijiazhuang, 050017, China
| | - Yishuo Shi
- Department of Neurobiology, Hebei Medical University, Shijiazhuang, 050017, China
| | - Wei Liu
- Department of Neurobiology, Hebei Medical University, Shijiazhuang, 050017, China
| | - Yanming Tian
- Department of Neurobiology, Hebei Medical University, Shijiazhuang, 050017, China
| | - Sheng Wang
- Department of Neurobiology, Hebei Medical University, Shijiazhuang, 050017, China.
- Hebei Key Laboratory of Neurophysiology, Shijiazhuang, 050017, China.
| | - Fang Yuan
- Department of Neurobiology, Hebei Medical University, Shijiazhuang, 050017, China.
- Hebei Key Laboratory of Neurophysiology, Shijiazhuang, 050017, China.
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2
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Racine AS, Michon FX, Laplante I, Lacaille JC. Somatostatin contributes to long-term potentiation at excitatory synapses onto hippocampal somatostatinergic interneurons. Mol Brain 2021; 14:130. [PMID: 34429141 PMCID: PMC8385910 DOI: 10.1186/s13041-021-00830-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Accepted: 07/13/2021] [Indexed: 04/13/2023] Open
Abstract
Somatostatin-expressing interneurons (SOM-INs) are a major subpopulation of GABAergic cells in CA1 hippocampus that receive excitation from pyramidal cells (PCs), and, in turn, provide feedback inhibition onto PC dendrites. Excitatory synapses onto SOM-INs show a Hebbian long-term potentiation (LTP) mediated by type 1a metabotropic glutamate receptors (mGluR1a) that is implicated in hippocampus-dependent learning. The neuropeptide somatostatin (SST) is also critical for hippocampal long-term synaptic plasticity, as well as learning and memory. SST effects on hippocampal PCs are well documented, but its actions on inhibitory interneurons remain largely undetermined. In the present work, we investigate the involvement of SST in long-term potentiation of CA1 SOM-IN excitatory synapses using pharmacological approaches targeting the somatostatinergic system and whole cell recordings in slices from transgenic mice expressing eYFP in SOM-INs. We report that application of exogenous SST14 induces long-term potentiation of excitatory postsynaptic potentials in SOM-INs via somatostatin type 1–5 receptors (SST1-5Rs) but does not affect synapses of PC or parvalbumin-expressing interneurons. Hebbian LTP in SOM-INs was prevented by inhibition of SSTRs and by depletion of SST by cysteamine treatment, suggesting a critical role of endogenous SST in LTP. LTP of SOM-IN excitatory synapses induced by SST14 was independent of NMDAR and mGluR1a, activity-dependent, and prevented by blocking GABAA receptor function. Our results indicate that endogenous SST may contribute to Hebbian LTP at excitatory synapses of SOM-INs by controlling GABAA inhibition, uncovering a novel role for SST in regulating long-term synaptic plasticity in somatostatinergic cells that may be important for hippocampus-dependent memory processes.
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Affiliation(s)
- Anne-Sophie Racine
- Centre for Interdisciplinary Research on Brain and Learning, Research Group on the Central Nervous System, Department of Neurosciences, Université de Montréal, P.O. Box 6128, Station Downtown, Montreal, QC, H3C 3J7, Canada
| | - François-Xavier Michon
- Centre for Interdisciplinary Research on Brain and Learning, Research Group on the Central Nervous System, Department of Neurosciences, Université de Montréal, P.O. Box 6128, Station Downtown, Montreal, QC, H3C 3J7, Canada
| | - Isabel Laplante
- Centre for Interdisciplinary Research on Brain and Learning, Research Group on the Central Nervous System, Department of Neurosciences, Université de Montréal, P.O. Box 6128, Station Downtown, Montreal, QC, H3C 3J7, Canada
| | - Jean-Claude Lacaille
- Centre for Interdisciplinary Research on Brain and Learning, Research Group on the Central Nervous System, Department of Neurosciences, Université de Montréal, P.O. Box 6128, Station Downtown, Montreal, QC, H3C 3J7, Canada.
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3
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Cinelli E, Mutolo D, Pantaleo T, Bongianni F. Neural mechanisms underlying respiratory regulation within the preBötzinger complex of the rabbit. Respir Physiol Neurobiol 2021; 293:103736. [PMID: 34224867 DOI: 10.1016/j.resp.2021.103736] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Revised: 07/01/2021] [Accepted: 07/01/2021] [Indexed: 11/29/2022]
Abstract
The preBötzinger complex (preBötC) is a medullary area essential for normal breathing and widely recognized as necessary and sufficient to generate the inspiratory phase of respiration. It has been studied mainly in rodents. Here we report the main results of our studies revealing the characteristics of the rabbit preBötC identified by means of neuronal recordings, D,L-homocysteic acid microinjections and histological controls. A crucial role in the respiratory rhythmogenesis within this neural substrate is played by excitatory amino acids, but also GABA and glycine display important contributions. Increases in respiratory frequency are induced by microinjections of neurokinins, somatostatin as well by serotonin (5-HT) through an action on 5-HT1A and 5-HT3 receptors or the disinhibition of a GABAergic circuit. Respiratory depression is observed in response to microinjections of the μ-opioid receptor agonist DAMGO. Our results show similarities and differences with the rodent preBötC and emphasize the importance of comparative studies on the mechanisms underlying respiratory rhythmogenesis in different animal species.
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Affiliation(s)
- Elenia Cinelli
- Dipartimento di Medicina Sperimentale e Clinica, Sezione Scienze Fisiologiche, Università Degli Studi di Firenze, Viale G.B. Morgagni 63, Firenze, 50134, Italy
| | - Donatella Mutolo
- Dipartimento di Medicina Sperimentale e Clinica, Sezione Scienze Fisiologiche, Università Degli Studi di Firenze, Viale G.B. Morgagni 63, Firenze, 50134, Italy
| | - Tito Pantaleo
- Dipartimento di Medicina Sperimentale e Clinica, Sezione Scienze Fisiologiche, Università Degli Studi di Firenze, Viale G.B. Morgagni 63, Firenze, 50134, Italy
| | - Fulvia Bongianni
- Dipartimento di Medicina Sperimentale e Clinica, Sezione Scienze Fisiologiche, Università Degli Studi di Firenze, Viale G.B. Morgagni 63, Firenze, 50134, Italy.
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4
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Stengel A, Taché Y. Central somatostatin signaling and regulation of food intake. Ann N Y Acad Sci 2019; 1455:98-104. [PMID: 31237362 DOI: 10.1111/nyas.14178] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Revised: 05/20/2019] [Accepted: 06/03/2019] [Indexed: 12/29/2022]
Abstract
The discovery of somatostatin (SST) in the hypothalamus implicated the peptide in the inhibition of growth hormone release. However, as observed for numerous neuropeptides, SST was neither restricted to this one brain site nor to this one function. Subsequent studies established a widespread but specific expression of SST in the central nervous system of rodents and humans along with the expression patterns of five receptors (sst1-5 ). Among biological actions, the activation of central SST signaling induced a robust stimulation of food and water intake, which is mediated by the sst2 as assessed using selective sst agonists. The past years have witnessed the identification of brain SST circuitries involved using chemogenetic and optogenetic approaches and further established a physiological orexigenic role of brain SST signaling. The present review will discuss these recent findings.
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Affiliation(s)
- Andreas Stengel
- Charité Center for Internal Medicine and Dermatology, Department for Psychosomatic Medicine, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Berlin, Germany.,Department of Psychosomatic Medicine and Psychotherapy, Medical University Hospital Tübingen, Tübingen, Germany
| | - Yvette Taché
- Department of Medicine, CURE: Digestive Diseases Research Center, Vatche and Tamar Manoukian Division of Digestive Diseases, David Geffen School of Medicine, UCLA, Los Angeles, California.,VA Greater Los Angeles Healthcare System, Los Angeles, California
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5
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Ligand design for somatostatin receptor isoforms 4 and 5. Eur J Med Chem 2019; 163:148-159. [DOI: 10.1016/j.ejmech.2018.11.030] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Revised: 11/08/2018] [Accepted: 11/09/2018] [Indexed: 12/14/2022]
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6
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Stengel A, Taché YF. Activation of Brain Somatostatin Signaling Suppresses CRF Receptor-Mediated Stress Response. Front Neurosci 2017; 11:231. [PMID: 28487631 PMCID: PMC5403923 DOI: 10.3389/fnins.2017.00231] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Accepted: 04/06/2017] [Indexed: 12/30/2022] Open
Abstract
Corticotropin-releasing factor (CRF) is the hallmark brain peptide triggering the response to stress and mediates—in addition to the stimulation of the hypothalamus-pituitary-adrenal (HPA) axis—other hormonal, behavioral, autonomic and visceral components. Earlier reports indicate that somatostatin-28 injected intracerebroventricularly counteracts the acute stress-induced ACTH and catecholamine release. Mounting evidence now supports that activation of brain somatostatin signaling exerts a broader anti-stress effect by blunting the endocrine, autonomic, behavioral (with a focus on food intake) and visceral gastrointestinal motor responses through the involvement of distinct somatostatin receptor subtypes.
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Affiliation(s)
- Andreas Stengel
- Division of Psychosomatic Medicine, Charité Center for Internal Medicine and Dermatology, Charité-Universitätsmedizin BerlinBerlin, Germany
| | - Yvette F Taché
- Vatche and Tamar Manoukian Digestive Diseases Division, CURE Digestive Diseases Research Center, G Oppenheimer Center for Neurobiology of Stress and Resilience, Department of Medicine, University of California, Los AngelesLos Angeles, CA, USA.,VA Greater Los Angeles Health Care SystemLos Angeles, CA, USA
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7
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Le S, Turner AJ, Parker LM, Burke PG, Kumar NN, Goodchild AK, McMullan S. Somatostatin 2a receptors are not expressed on functionally identified respiratory neurons in the ventral respiratory column of the rat. J Comp Neurol 2015; 524:1384-98. [PMID: 26470751 DOI: 10.1002/cne.23912] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2015] [Revised: 10/09/2015] [Accepted: 10/12/2015] [Indexed: 01/09/2023]
Abstract
Microinjection of somatostatin (SST) causes site-specific effects on respiratory phase transition, frequency, and amplitude when microinjected into the ventrolateral medulla (VLM) of the anesthetized rat, suggesting selective expression of SST receptors on different functional classes of respiratory neurons. Of the six subtypes of SST receptor, somatostatin 2a (sst2a ) is the most prevalent in the VLM, and other investigators have suggested that glutamatergic neurons in the preBötzinger Complex (preBötC) that coexpress neurokinin-1 receptor (NK1R), SST, and sst2a are critical for the generation of respiratory rhythm. However, quantitative data describing the distribution of sst2a in respiratory compartments other than preBötC, or on functionally identified respiratory neurons, is absent. Here we examine the medullary expression of sst2a with particular reference to glycinergic/expiratory neurons in the Bötzinger Complex (BötC) and NK1R-immunoreactive/inspiratory neurons in the preBötC. We found robust sst2a expression at all rostrocaudal levels of the VLM, including a large proportion of catecholaminergic neurons, but no colocalization of sst2a and glycine transporter 2 mRNA in the BötC. In the preBötC 54% of sst2a -immunoreactive neurons were also positive for NK1R. sst2a was not observed in any of 52 dye-labeled respiratory interneurons, including seven BötC expiratory-decrementing and 11 preBötC preinspiratory neurons. We conclude that sst2a is not expressed on BötC respiratory neurons and that phasic respiratory activity is a poor predictor of sst2a expression in the preBötC. Therefore, sst2a is unlikely to underlie responses to BötC SST injection, and is sparse or absent on respiratory neurons identified by classical functional criteria. J. Comp. Neurol. 524:1384-1398, 2016. © 2015 Wiley Periodicals, Inc.
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Affiliation(s)
- Sheng Le
- Faculty of Medicine & Health Sciences, Macquarie University, NSW, Australia
| | - Anita J Turner
- Faculty of Medicine & Health Sciences, Macquarie University, NSW, Australia
| | - Lindsay M Parker
- ARC Center of Excellence for Nanoscale BioPhotonics, Macquarie University, NSW, Australia
| | - Peter G Burke
- Neuroscience Research Australia, Randwick, NSW, Australia
| | - Natasha N Kumar
- Department of Pharmacology, University of Virginia, Charlottesville, Virginia, USA
| | - Ann K Goodchild
- Faculty of Medicine & Health Sciences, Macquarie University, NSW, Australia
| | - Simon McMullan
- Faculty of Medicine & Health Sciences, Macquarie University, NSW, Australia
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8
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Sánchez ML, Vecino E, Coveñas R. Distribution of Neurotensin and Somatostatin-28 (1-12) in the Minipig Brainstem. Anat Histol Embryol 2015; 45:260-76. [PMID: 26250798 DOI: 10.1111/ahe.12194] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2014] [Accepted: 07/05/2015] [Indexed: 11/29/2022]
Abstract
Using an indirect immunoperoxidase technique, an in depth study has been carried out for the first time on the distribution of fibres and cell bodies containing neurotensin and somatostatin-28 (1-12) (SOM) in the minipig brainstem. The animals used were not treated with colchicine. The distribution of neurotensin- and SOM-immunoreactive fibres was seen to be quite similar and was moderate in the minipig brainstem: a close anatomical relationship between both neuropeptides was observed. The distribution of cell bodies containing neurotensin or SOM was quite different and restricted. Cell bodies containing neurotensin were found in four brainstem nuclei: nucleus centralis raphae, nucleus dorsalis raphae, in the pars centralis of the nucleus tractus spinalis nervi trigemini and in the nucleus ventralis raphae. Cell bodies containing SOM were found in six nuclei/regions of the brainstem: nucleus ambiguus, nucleus dorsalis motorius nervi vagus, formatio reticularis, nucleus parabrachialis medialis, nucleus reticularis lateralis and nucleus ventralis raphae. According to the observed anatomical distribution of the immunoreactive structures containing neurotensin or SOM, the peptides could be involved in sleep-waking, nociceptive, gustatory, motor, respiratory and autonomic mechanisms.
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Affiliation(s)
- M L Sánchez
- Laboratory of Neuroanatomy of the Peptidergic Systems, Institute of Neurosciences of Castilla y León (INCYL), University of Salamanca, c/Pintor Fernando Gallego, 1, 37007, Salamanca, Spain
| | - E Vecino
- Department of Cell Biology and Histology, University of the Basque Country, UPV/EHU, 48940, Leioa, Spain
| | - R Coveñas
- Laboratory of Neuroanatomy of the Peptidergic Systems, Institute of Neurosciences of Castilla y León (INCYL), University of Salamanca, c/Pintor Fernando Gallego, 1, 37007, Salamanca, Spain
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9
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Bou Farah L, Bowman BR, Bokiniec P, Karim S, Le S, Goodchild AK, McMullan S. Somatostatin in the rat rostral ventrolateral medulla: Origins and mechanism of action. J Comp Neurol 2015; 524:323-42. [PMID: 26131686 DOI: 10.1002/cne.23846] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2015] [Revised: 06/22/2015] [Accepted: 06/23/2015] [Indexed: 01/24/2023]
Abstract
Somatostatin (SST) or agonists of the SST-2 receptor (sst2 ) in the rostral ventrolateral medulla (RVLM) lower sympathetic nerve activity, arterial pressure, and heart rate, or when administered within the Bötzinger region, evoke apneusis. Our aims were to describe the mechanisms responsible for the sympathoinhibitory effects of SST on bulbospinal neurons and to identify likely sources of RVLM SST release. Patch clamp recordings were made from bulbospinal RVLM neurons (n = 31) in brainstem slices prepared from juvenile rat pups. Overall, 58% of neurons responded to SST, displaying an increase in conductance that reversed at -93 mV, indicative of an inwardly rectifying potassium channel (GIRK) mechanism. Blockade of sst2 abolished this effect, but application of tetrodotoxin did not, indicating that the SST effect is independent of presynaptic activity. Fourteen bulbospinal RVLM neurons were recovered for immunohistochemistry; nine were SST-insensitive and did not express sst2a . Three out of five responsive neurons were sst2a -immunoreactive. Neurons that contained preprosomatostatin mRNA and cholera-toxin-B retrogradely transported from the RVLM were detected in: paratrigeminal nucleus, lateral parabrachial nucleus, Kölliker-Fuse nucleus, ventrolateral periaqueductal gray area, central nucleus of the amygdala, sublenticular extended amygdala, interstitial nucleus of the posterior limb of the anterior commissure nucleus, and bed nucleus of the stria terminalis. Thus, those brain regions are putative sources of endogenous SST release that, when activated, may evoke sympathoinhibitory effects via interactions with subsets of sympathetic premotor neurons that express sst2 .
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Affiliation(s)
- Lama Bou Farah
- Australian School of Advanced Medicine, Macquarie University, 2109, NSW, Australia
| | - Belinda R Bowman
- Australian School of Advanced Medicine, Macquarie University, 2109, NSW, Australia
| | - Phil Bokiniec
- Australian School of Advanced Medicine, Macquarie University, 2109, NSW, Australia
| | - Shafinaz Karim
- Australian School of Advanced Medicine, Macquarie University, 2109, NSW, Australia
| | - Sheng Le
- Australian School of Advanced Medicine, Macquarie University, 2109, NSW, Australia
| | - Ann K Goodchild
- Australian School of Advanced Medicine, Macquarie University, 2109, NSW, Australia
| | - Simon McMullan
- Australian School of Advanced Medicine, Macquarie University, 2109, NSW, Australia
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10
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Stengel A, Karasawa H, Taché Y. The role of brain somatostatin receptor 2 in the regulation of feeding and drinking behavior. Horm Behav 2015; 73:15-22. [PMID: 26026616 PMCID: PMC4546908 DOI: 10.1016/j.yhbeh.2015.05.009] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2015] [Revised: 05/13/2015] [Accepted: 05/18/2015] [Indexed: 12/13/2022]
Abstract
Somatostatin was discovered four decades ago as hypothalamic factor inhibiting growth hormone release. Subsequently, somatostatin was found to be widely distributed throughout the brain and to exert pleiotropic actions via interaction with five somatostatin receptors (sst1-5) that are also widely expressed throughout the brain. Interestingly, in contrast to the predominantly inhibitory actions of peripheral somatostatin, the activation of brain sst2 signaling by intracerebroventricular injection of stable somatostatin agonists potently stimulates food intake and independently, drinking behavior in rodents. The orexigenic response involves downstream orexin-1, neuropeptide Y1 and μ receptor signaling while the dipsogenic effect is mediated through the activation of the brain angiotensin 1 receptor. Brain sst2 activation is part of mechanisms underlying the stimulation of feeding and more prominently water intake in the dark phase and is able to counteract the anorexic response to visceral stressors.
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Affiliation(s)
- Andreas Stengel
- Charité Center for Internal Medicine and Dermatology, Division of General Internal and Psychosomatic Medicine, Charité-Universitätsmedizin Berlin, Campus Benjamin Franklin, Berlin, Germany
| | - Hiroshi Karasawa
- CURE: Digestive Diseases Research Center, Center for Neurobiology of Stress and Women's Health, Department of Medicine, Digestive Diseases Division at the University of California Los Angeles, and VA Greater Los Angeles Health Care System, CA 90073, USA
| | - Yvette Taché
- CURE: Digestive Diseases Research Center, Center for Neurobiology of Stress and Women's Health, Department of Medicine, Digestive Diseases Division at the University of California Los Angeles, and VA Greater Los Angeles Health Care System, CA 90073, USA.
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11
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Stengel A, Rivier J, Taché Y. Central actions of somatostatin-28 and oligosomatostatin agonists to prevent components of the endocrine, autonomic and visceral responses to stress through interaction with different somatostatin receptor subtypes. Curr Pharm Des 2013; 19:98-105. [PMID: 22950508 DOI: 10.2174/13816128130114] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2012] [Accepted: 07/30/2012] [Indexed: 01/23/2023]
Abstract
Somatostatin was discovered four decades ago and since then its physiological role has been extensively investigated, first in relation with its inhibitory effect on growth hormone secretion but soon it expanded to extrapituitary actions influencing various stressresponsive systems. Somatostatin is expressed in distinct brain nuclei and binds to five somatostatin receptor subtypes which are also widely expressed in the brain with a distinct distribution pattern. The last few years witnessed the discovery of highly selective peptide somatostatin receptor agonists and antagonists representing valuable tools to delineate the respective pathways of somatostatin signaling. Here we review the centrally mediated actions of somatostatin and related selective somatostatin receptor subtype agonists to influence the endocrine, autonomic, and visceral components of the stress response and basal behavior as well as thermogenesis.
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Affiliation(s)
- Andreas Stengel
- CURE: Digestive Diseases Research Center and Center for Neurovisceral Sciences & Women's Health, Digestive Diseases Division, David Geffen School of Medicine at UCLA and VA Greater Los Angeles Healthcare System, Los Angeles, California, USA
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12
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Stengel A, Rivier J, Taché Y. Modulation of the adaptive response to stress by brain activation of selective somatostatin receptor subtypes. Peptides 2013; 42:70-7. [PMID: 23287111 PMCID: PMC3633742 DOI: 10.1016/j.peptides.2012.12.022] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/16/2012] [Revised: 12/21/2012] [Accepted: 12/21/2012] [Indexed: 01/06/2023]
Abstract
Somatostatin-14 was discovered in 1973 in the hypothalamus as a peptide inhibiting growth hormone release. Somatostatin interacts with five receptor subtypes (sst(1-5)) which are widely distributed in the brain with a distinct, but overlapping, expression pattern. During the last few years, the development of highly selective peptide agonists and antagonists provided new insight to characterize the role of somatostatin receptor subtypes in the pleiotropic actions of somatostatin. Recent evidence in rodents indicates that the activation of selective somatostatin receptor subtypes in the brain blunts stress-corticotropin-releasing factor (CRF) related ACTH release (sst2/5), sympathetic-adrenal activaton (sst5), stimulation of colonic motility (sst1), delayed gastric emptying (sst5), suppression of food intake (sst2) and the anxiogenic-like (sst2) response. These findings suggest that brain somatostatin signaling pathways may play an important role in dampening CRF-mediated endocrine, sympathetic, behavioral and visceral responses to stress.
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Affiliation(s)
- Andreas Stengel
- CURE: Digestive Diseases Research Center and Center for Neurovisceral Sciences & Women's Health, Digestive Diseases Division, David Geffen School of Medicine at UCLA and VA Greater Los Angeles Healthcare System, Los Angeles, California, USA
- Division of Psychosomatic Medicine & Obesity Center Berlin, Department of Medicine, Charité Medical Center and University, Berlin, Germany
| | - Jean Rivier
- Peptide Biology Laboratories, Salk Institute, La Jolla, California, USA
| | - Yvette Taché
- CURE: Digestive Diseases Research Center and Center for Neurovisceral Sciences & Women's Health, Digestive Diseases Division, David Geffen School of Medicine at UCLA and VA Greater Los Angeles Healthcare System, Los Angeles, California, USA
- Address: CURE: Digestive Diseases Research Center, Building 115, Room 117, VA Greater Los Angeles Healthcare System, 11301 Wilshire Boulevard, Los Angeles, CA 90073, Phone: 310-312-9275, Fax: 1-310-268-4963,
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13
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Chen CY, Chern RS, Liao MH, Chang YH, Hsu JYC, Chien CH. The Possible Neuronal Mechanism of Acupuncture: Morphological Evidence of the Neuronal Connection between Groin A-Shi Point and Uterus. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE : ECAM 2013; 2013:429186. [PMID: 23533481 PMCID: PMC3603327 DOI: 10.1155/2013/429186] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/08/2012] [Accepted: 01/25/2013] [Indexed: 11/17/2022]
Abstract
Somatovisceral reflex suggested that the somatic stimulation could affect visceral function like acupuncture which treats diseases by stimulating acupoints. The neuronal connection between somatic point and visceral organ was not clear. Uterine pain referred to the groin region has long been recognized clinically. Wesselmann, using neurogenic plasma extravasation method, showed that uterine pain was referred to the groin region through a neuronal mechanism (Wesselmann and Lai 1997). This connection could be considered through the somatovisceral reflex pathway. However, the relay center of this pathway is still not clearly identified. In the present study, bee venom was injected in the groin region to induce central Fos expression to map the sensory innervation of groin region. Pseudorabies virus (PrV), a transneuronal tracer, was injected in the uterus to identify the higher motor control of the uterus. Immunohistochemistry staining revealed the Fos expression and PrV-infected double-labeled neurons in the nucleus of solitary tract (NTS), the dorsal motor nucleus of vagus (DMX), and the paraventricular hypothalamic nucleus (PVN). These results suggest a somatoparasympathetic neuronal connection (groin-spinal dorsal horn-NTS/DMX-uterus) and a somatosympathetic neuronal connection (groin-spinal dorsal horn-NTS-PVN-uterus). These two neuronal connections could be the prerequisites to the neuronal basis of the somatovisceral reflex and also the neuronal mechanism of acupuncture.
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Affiliation(s)
- Chun-Yen Chen
- Department of Cell Biology and Anatomy, College of Medicine, National Cheng-Kung University, Tainan, Taiwan
| | - Rey-Shyong Chern
- Graduate Institute and Department of Veterinary Medicine, College of Veterinary Medicine, National Pingtung University of Science and Technology, 1, Shuefu Road, Neipu, Pingtung 912, Taiwan
| | - Ming-Huei Liao
- Graduate Institute and Department of Veterinary Medicine, College of Veterinary Medicine, National Pingtung University of Science and Technology, 1, Shuefu Road, Neipu, Pingtung 912, Taiwan
| | - Yung-Hsien Chang
- Graduate Institute of Chinese Medical Science, China Medical University, Taichung, Taiwan
| | - Jung-Yu C. Hsu
- Department of Cell Biology and Anatomy, College of Medicine, National Cheng-Kung University, Tainan, Taiwan
| | - Chi-Hsien Chien
- Graduate Institute and Department of Veterinary Medicine, College of Veterinary Medicine, National Pingtung University of Science and Technology, 1, Shuefu Road, Neipu, Pingtung 912, Taiwan
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14
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Wei XY, Zhao Y, Wong-Riley MTT, Ju G, Liu YY. Synaptic relationship between somatostatin- and neurokinin-1 receptor-immunoreactive neurons in the pre-Bötzinger complex of rats. J Neurochem 2012; 122:923-33. [DOI: 10.1111/j.1471-4159.2012.07862.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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15
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Parker LM, Tallapragada VJ, Kumar NN, Goodchild AK. Distribution and localisation of Gα proteins in the rostral ventrolateral medulla of normotensive and hypertensive rats: focus on catecholaminergic neurons. Neuroscience 2012; 218:20-34. [PMID: 22626648 DOI: 10.1016/j.neuroscience.2012.05.037] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2012] [Revised: 05/11/2012] [Accepted: 05/12/2012] [Indexed: 02/07/2023]
Abstract
About 860 G-protein-coupled receptors (GPCRs) mediate their actions via heterotrimeric G-proteins. Their activation releases Gα from Gβλ subunits. The type of Gα subunit dictates the major signalling proteins involved: adenylyl cyclase, PLC and rhoGEF. The rostral ventrolateral medulla (RVLM), containing the rostral C1 (rC1) cell group, sets and maintains the tonic and reflex control of blood pressure and a plethora of inputs converge onto these neurons. We determined the relative abundance of 10 Gα subunit mRNAs, representing the four major families, within the RVLM, using quantitative RT-PCR. In situ hybridisation (ISH) combined with immunohistochemistry (IHC) was used to quantify and compare this expression in rC1 with that in the A1 and A5 cell groups. The relative abundance of Gα subunit mRNAs and a comparison of gene expression levels were quantitatively determined in normotensive and hypertensive rat strains. All 10 Gα mRNAs were detected in the RVLM of Sprague-Dawley (SD) rats with relative abundance such that Gαs>Gαi2>Gαo>Gαq>GαL>Gα11>Gαi3>Gαi1>Gα12>Gα13. The high abundance of Gα mRNAs signalling via adenylyl cyclase indicates the importance of associated GPCRs. Within the rC1 and A1 groups similar differential Gα mRNA expression profiles were seen with Gαs being found in all rC1 cells, Gα11 absent and Gαi3 rarely expressed. Thus functionally distinct subgroups exist within the rC1 and A1 cell groups as differing distributions of Gα subunits must reflect the array of GPCRs that influence their activity. In contrast, all A5 cells expressed all Gα mRNAs suggesting a functionally homogeneous group. When the 10 Gα mRNAs of the RVLM in spontaneously hypertensive rats (SHR) were compared quantitatively to Wistar-Kyoto (WKY), only Gαs and Gα12 were significantly elevated. However when the expression in normotensive SD and WKY was compared with SHR no significant differences were evident. These findings demonstrate a range of GPCR signalling capabilities in brainstem neurons important for homeostasis and suggest a prominent role for signalling via adenylyl cyclase.
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Affiliation(s)
- L M Parker
- The Australian School of Advanced Medicine, 2 Technology Place, Macquarie University, 2109 NSW, Australia
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16
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Ramírez-Jarquín JO, Lara-Hernández S, López-Guerrero JJ, Aguileta MA, Rivera-Angulo AJ, Sampieri A, Vaca L, Ordaz B, Peña-Ortega F. Somatostatin modulates generation of inspiratory rhythms and determines asphyxia survival. Peptides 2012; 34:360-72. [PMID: 22386651 DOI: 10.1016/j.peptides.2012.02.011] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/09/2011] [Revised: 02/15/2012] [Accepted: 02/15/2012] [Indexed: 10/28/2022]
Abstract
Breathing and the activity of its generator (the pre-Bötzinger complex; pre-BötC) are highly regulated functions. Among neuromodulators of breathing, somatostatin (SST) is unique: it is synthesized by a subset of glutamatergic pre-BötC neurons, but acts as an inhibitory neuromodulator. Moreover, SST regulates breathing both in normoxic and in hypoxic conditions. Although it has been implicated in the neuromodulation of breathing, neither the locus of SST modulation, nor the receptor subtypes involved have been identified. In this study, we aimed to fill in these blanks by characterizing the SST-induced regulation of inspiratory rhythm generation in vitro and in vivo. We found that both endogenous and exogenous SST depress all preBötC-generated rhythms. While SST abolishes sighs, it also decreases the frequency and increases the regularity of eupnea and gasping. Pharmacological experiments showed that SST modulates inspiratory rhythm generation by activating SST receptor type-2, whose mRNA is abundantly expressed in the pre-Bötzinger complex. In vivo, blockade of SST receptor type-2 reduces gasping amplitude and consequently, it precludes auto-resuscitation after asphyxia. Based on our findings, we suggest that SST functions as an inhibitory neuromodulator released by excitatory respiratory neurons when they become overactivated in order to stabilize breathing rhythmicity in normoxic and hypoxic conditions.
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Affiliation(s)
- Josué O Ramírez-Jarquín
- Departamento de Neurobiología del Desarrollo y Neurofisiología, Instituto de Neurobiología, UNAM-Campus Juriquilla, Mexico.
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17
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Stengel A, Taché Y. Activation of somatostatin 2 receptors in the brain and the periphery induces opposite changes in circulating ghrelin levels: functional implications. Front Endocrinol (Lausanne) 2012; 3:178. [PMID: 23335913 PMCID: PMC3542632 DOI: 10.3389/fendo.2012.00178] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/11/2012] [Accepted: 12/17/2012] [Indexed: 12/26/2022] Open
Abstract
Somatostatin is an important modulator of neurotransmission in the central nervous system and acts as a potent inhibitor of hormone and exocrine secretion and regulator of cell proliferation in the periphery. These pleiotropic actions occur through interaction with five G protein-coupled somatostatin receptor subtypes (sst(1) (-) (5)) that are widely expressed in the brain and peripheral organs. The characterization of somatostatin's effects can be investigated by pharmacological or genetic approaches using newly developed selective sst agonists and antagonists and mice lacking specific sst subtypes. Recent evidence points toward a divergent action of somatostatin in the brain and in the periphery to regulate circulating levels of ghrelin, an orexigenic hormone produced by the endocrine X/A-like cells in the rat gastric mucosa. Somatostatin interacts with the sst(2) in the brain to induce an increase in basal ghrelin plasma levels and counteracts the visceral stress-related decrease in circulating ghrelin. By contrast, stimulation of peripheral somatostatin-sst(2) signaling results in the inhibition of basal ghrelin release and mediates the postoperative decrease in circulating ghrelin. The peripheral sst(2)-mediated reduction of plasma ghrelin is likely to involve a paracrine action of D cell-derived somatostatin acting on sst(2) bearing X/A-like ghrelin cells in the gastric mucosa. The other member of the somatostatin family, named cortistatin, in addition to binding to sst(1) (-) (5) also directly interacts with the ghrelin receptor and therefore may simultaneously modulate ghrelin release and actions at target sites bearing ghrelin receptors representing a link between the ghrelin and somatostatin systems.
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Affiliation(s)
- Andreas Stengel
- Division Psychosomatic Medicine and Psychotherapy, Department of Medicine, Obesity Center Berlin, Charité, Universitätsmedizin BerlinBerlin, Germany
- *Correspondence: Andreas Stengel, Division Psychosomatic Medicine and Psychotherapy, Department of Medicine, Obesity Center Berlin, Charité, Universitätsmedizin Berlin, Luisenstr. 13a, 10117 Berlin, Germany. e-mail: ; Yvette Taché, Digestive Diseases Division, CURE: Digestive Diseases Research Center, Center for Neurobiology of Stress and Women’s Health, Department of Medicine, VA Greater Los Angeles Health Care System, University of California at Los Angeles, CURE Building 115, Room 117, 11301 Wilshire Boulevard, Los Angeles, CA 90073, USA. e-mail:
| | - Yvette Taché
- Digestive Diseases Division, CURE: Digestive Diseases Research Center, Center for Neurobiology of Stress and Women’s Health, Department of Medicine, VA Greater Los Angeles Health Care System, University of California at Los AngelesLos Angeles, CA, USA
- *Correspondence: Andreas Stengel, Division Psychosomatic Medicine and Psychotherapy, Department of Medicine, Obesity Center Berlin, Charité, Universitätsmedizin Berlin, Luisenstr. 13a, 10117 Berlin, Germany. e-mail: ; Yvette Taché, Digestive Diseases Division, CURE: Digestive Diseases Research Center, Center for Neurobiology of Stress and Women’s Health, Department of Medicine, VA Greater Los Angeles Health Care System, University of California at Los Angeles, CURE Building 115, Room 117, 11301 Wilshire Boulevard, Los Angeles, CA 90073, USA. e-mail:
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Martel G, Dutar P, Epelbaum J, Viollet C. Somatostatinergic systems: an update on brain functions in normal and pathological aging. Front Endocrinol (Lausanne) 2012; 3:154. [PMID: 23230430 PMCID: PMC3515867 DOI: 10.3389/fendo.2012.00154] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/11/2012] [Accepted: 11/20/2012] [Indexed: 11/29/2022] Open
Abstract
Somatostatin is highly expressed in mammalian brain and is involved in many brain functions such as motor activity, sleep, sensory, and cognitive processes. Five somatostatin receptors have been described: sst(1), sst(2) (A and B), sst(3), sst(4), and sst(5), all belonging to the G-protein-coupled receptor family. During the recent years, numerous studies contributed to clarify the role of somatostatin systems, especially long-range somatostatinergic interneurons, in several functions they have been previously involved in. New advances have also been made on the alterations of somatostatinergic systems in several brain diseases and on the potential therapeutic target they represent in these pathologies.
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Affiliation(s)
| | | | | | - Cécile Viollet
- *Correspondence: Cécile Viollet, Inserm UMR894 - Center for Psychiatry and Neuroscience, Université Paris Descartes, Sorbonne Paris Cité, 2 ter rue d’Alésia, 75014 Paris, France. e-mail:
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19
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Respiratory responses to somatostatin microinjections into the Bötzinger complex and the pre-Bötzinger complex of the rabbit. Neurosci Lett 2011; 498:26-30. [DOI: 10.1016/j.neulet.2011.04.054] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2011] [Revised: 04/20/2011] [Accepted: 04/21/2011] [Indexed: 11/19/2022]
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20
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Burke P, Abbott S, McMullan S, Goodchild A, Pilowsky P. Somatostatin selectively ablates post-inspiratory activity after injection into the Bötzinger complex. Neuroscience 2010; 167:528-39. [DOI: 10.1016/j.neuroscience.2010.01.065] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2009] [Revised: 01/15/2010] [Accepted: 01/30/2010] [Indexed: 11/26/2022]
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21
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Kaczyńska K, Szereda-Przestaszewska M. Depressive cardio-respiratory effects of somatostatin in anaesthetized rats. Respir Physiol Neurobiol 2010; 170:273-8. [DOI: 10.1016/j.resp.2010.01.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2009] [Revised: 01/13/2010] [Accepted: 01/14/2010] [Indexed: 11/16/2022]
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22
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Cammalleri M, Martini D, Timperio AM, Bagnoli P. Functional effects of somatostatin receptor 1 activation on synaptic transmission in the mouse hippocampus. J Neurochem 2009; 111:1466-77. [PMID: 19811607 DOI: 10.1111/j.1471-4159.2009.06423.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Somatostatin-14 (SRIF) co-localizes with GABA in the hippocampus and regulates neuronal excitability. A role of SRIF in the control of hippocampal activity has been proposed, although the exact contribution of each SRIF receptor (sst(1)-sst(5)) in mediating SRIF action requires some clarification. We used hippocampal slices of wild-type and sst(1) knockout (KO) mice and selective pharmacological tools to provide conclusive evidence for a role of sst(1) in mediating SRIF inhibition of synaptic transmission. With single- and double-label immunohistochemistry, we determined the distribution of sst(1) in hippocampal slices and we quantified sst(1) colocalization with SRIF. With electrophysiology, we found that sst(1) activation with CH-275 inhibited both the NMDA- and the alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA)-mediated responses. Results from sst(1) KO slices confirmed the specificity of CH-275 effects; sst(1) activation did not affect the inhibitory transmission which was in contrast increased by sst(4) activation with L-803,087 in both wild-type and sst(1) KO slices. The AMPA-mediated responses were increased by L-803,087. Functional interaction between sst(1) and sst(4) is suggested by the finding that their combined activation prevented the CH-275-induced inhibition of AMPA transmission. The involvement of pre-synaptic mechanisms in mediating inhibitory effects of sst(1) on excitatory transmission was demonstrated by the finding that CH-275 (i) increased the paired-pulse facilitation ratio, (ii) did not influence the AMPA depolarization in the presence of tetrodotoxin, and (iii) inhibited glutamate release induced by epileptiform treatment. We conclude that SRIF control of excitatory transmission through an action at sst(1) may represent an important contribution to the regulation of hippocampal activity.
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Affiliation(s)
- Maurizio Cammalleri
- Department of Biology, Unit of General Physiology, University of Pisa, Pisa, Italy
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23
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Burke PG, Li Q, Costin ML, McMullan S, Pilowsky PM, Goodchild AK. Somatostatin 2A Receptor-Expressing Presympathetic Neurons in the Rostral Ventrolateral Medulla Maintain Blood Pressure. Hypertension 2008; 52:1127-33. [DOI: 10.1161/hypertensionaha.108.118224] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Peter G.R. Burke
- From the Australian School of Advanced Medicine, Macquarie University, New South Wales, Australia
| | - Qun Li
- From the Australian School of Advanced Medicine, Macquarie University, New South Wales, Australia
| | - Monique L. Costin
- From the Australian School of Advanced Medicine, Macquarie University, New South Wales, Australia
| | - Simon McMullan
- From the Australian School of Advanced Medicine, Macquarie University, New South Wales, Australia
| | - Paul M. Pilowsky
- From the Australian School of Advanced Medicine, Macquarie University, New South Wales, Australia
| | - Ann K. Goodchild
- From the Australian School of Advanced Medicine, Macquarie University, New South Wales, Australia
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Kwak SE, Kim JE, Choi HC, Song HK, Kim YI, Jo SM, Kang TC. The expression of somatostatin receptors in the hippocampus of pilocarpine-induced rat epilepsy model. Neuropeptides 2008; 42:569-83. [PMID: 18951627 DOI: 10.1016/j.npep.2008.09.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2008] [Revised: 09/02/2008] [Accepted: 09/03/2008] [Indexed: 11/30/2022]
Abstract
During the course of this study, we sought examine whether the expression of somatostatin receptors (SSTRs) is altered in the hippocampus following pilocarpine-induced status epilepticus (SE) in order to understand the role/function of SSTRs in the hippocampus after epileptogenic insults. SSTR1 and SSTR4 immunoreactivities were increased in the hippocampus at 1 week after SE. At 4 weeks after SE, SRIF1-family (SSTR 2A, SSTR2B, and SSTR5) immunoreactivity was increased only in neuropil. Both SSTR2A and 2B immunoreactivities were increased in CA2-3 pyramidal cells. However, SSTR3 and SSTR4 immunoreactivities were reduced in the CA1 pyramidal cells of epileptic rat due to neuronal loss. In addition, SSTR5 immunoreactivity was reduced in CA2 pyramidal cells and various interneurons. Both SSTR2B and SSTR4 immunoreactivities were increased within microglia following SE. Our findings suggest that increases in neuron-glial SSTR expressions may be closely related to the enhanced inhibition of the dentate gyrus and regulation of reactive microgliosis in the hippocampus of a pilocarpine model of temporal lobe epilepsy.
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Affiliation(s)
- Sung-Eun Kwak
- Department of Anatomy and Neurobiology, College of Medicine, Hallym University, Chunchon 200-702, South Korea
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