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Inami C, Haruta M, Ohta Y, Tanaka M, So M, Sobue K, Akay Y, Kume K, Ohta J, Akay M, Ohsawa M. Real-time monitoring of cortical brain activity in response to acute pain using wide-area Ca 2+ imaging. Biochem Biophys Res Commun 2024; 708:149800. [PMID: 38522402 DOI: 10.1016/j.bbrc.2024.149800] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2024] [Accepted: 03/16/2024] [Indexed: 03/26/2024]
Abstract
Previous human and rodent studies indicated that nociceptive stimuli activate many brain regions that is involved in the somatosensory and emotional sensation. Although these studies have identified several important brain regions involved in pain perception, it has been a challenge to observe neural activity directly and simultaneously in these multiple brain regions during pain perception. Using a transgenic mouse expressing G-CaMP7 in majority of astrocytes and a subpopulation of excitatory neurons, we recorded the brain activity in the mouse cerebral cortex during acute pain stimulation. Both of hind paw pinch and intraplantar administration of formalin caused strong transient increase of the fluorescence in several cortical regions, including primary somatosensory, motor and retrosplenial cortex. This increase of the fluorescence intensity was attenuated by the pretreatment with morphine. The present study provides important insight into the cortico-cortical network during pain perception.
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Affiliation(s)
- Chihiro Inami
- Department of Neuropharmacology, Graduate School of Pharmaceutical Sciences, Nagoya City University, 3-1 Tanabe-dori, Mizuho-ku, Nagoya, 467-8603, Japan
| | - Makito Haruta
- Division of Materials Science, Graduate School of Science and Technology, Nara Institute of Science and Technology, 8916-5, Takayama, Ikoma-shi, Nara, Japan
| | - Yasumi Ohta
- Division of Materials Science, Graduate School of Science and Technology, Nara Institute of Science and Technology, 8916-5, Takayama, Ikoma-shi, Nara, Japan
| | - Motoshi Tanaka
- Department of Anesthesiology and Intensive Care Medicine, Graduate School of Medicine. Nagoya City University, 1 Kawasumi, Mizuho-ku, Nagoya, 467-8601, Japan
| | - MinHye So
- Department of Anesthesiology and Intensive Care Medicine, Graduate School of Medicine. Nagoya City University, 1 Kawasumi, Mizuho-ku, Nagoya, 467-8601, Japan
| | - Kazuya Sobue
- Department of Anesthesiology and Intensive Care Medicine, Graduate School of Medicine. Nagoya City University, 1 Kawasumi, Mizuho-ku, Nagoya, 467-8601, Japan
| | - Yasemin Akay
- Biomedical Engineering Department, University of Houston, 3517 Cullen Blvd, Houston, TX, 77204, USA
| | - Kazuhiko Kume
- Department of Neuropharmacology, Graduate School of Pharmaceutical Sciences, Nagoya City University, 3-1 Tanabe-dori, Mizuho-ku, Nagoya, 467-8603, Japan
| | - Jun Ohta
- Division of Materials Science, Graduate School of Science and Technology, Nara Institute of Science and Technology, 8916-5, Takayama, Ikoma-shi, Nara, Japan
| | - Metin Akay
- Biomedical Engineering Department, University of Houston, 3517 Cullen Blvd, Houston, TX, 77204, USA
| | - Masahiro Ohsawa
- Department of Neuropharmacology, Graduate School of Pharmaceutical Sciences, Nagoya City University, 3-1 Tanabe-dori, Mizuho-ku, Nagoya, 467-8603, Japan; Department of Integrative Neuroscience, National Center for Geriatrics and Gerontology, Obu, Aichi, 474-8511, Japan; Laboratory of Systems Pharmacology, Faculty of Pharma-Sciences, Teikyo University, Itabashi, Tokyo, 173-8603, Japan.
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Takahashi N, Akaike N, Nagamatsu T, Uchino H, Kudo Y. Effects of TND1128 (a 5-deazaflavin derivative), with self-redox ability, as a mitochondria activator on the mouse brain slice and its comparison with β-NMN. J Pharmacol Sci 2023; 151:93-109. [PMID: 36707184 DOI: 10.1016/j.jphs.2022.11.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2022] [Revised: 11/22/2022] [Accepted: 11/29/2022] [Indexed: 12/23/2022] Open
Abstract
We have no definitive treatment for dementia characterized by prolonged neuronal death due to the enormous accumulation of foreign matter, such as β-amyloid. Since Alzheimer's type dementia develops slowly, we may be able to delay the onset and improve neuronal dysfunction by enhancing the energy metabolism of individual neurons. TND1128, a derivative of 5-deazaflavin, is a chemical known to have an efficient self-redox ability. We expected TND1128 as an activator for mitochondrial energy synthesis. We used brain slices prepared from mice 22 ± 2 h pretreated with TND1128 or β-NMN. We measured Ca2+ concentrations in the cytoplasm ([Ca2+]cyt) and mitochondria ([Ca2+]mit) by using fluorescence Ca2+ indicators, Fura-4F, and X-Rhod-1, respectively, and examined the protective effects of drugs on [Ca2+]cyt and [Ca2+]mit overloading by repeating 80K exposure. TND1128 (0.01, 0.1, and 1 mg/kg s.c.) mitigates the dynamics of both [Ca2+]cyt and [Ca2+]mit in a dose-dependent manner. β-NMN (10, 30, and 100 mg/kg s.c.) also showed significant dose-dependent mitigating effects on [Ca2+]cyt, but the effect on the [Ca2+]mit dynamics was insignificant. We confirmed the mitochondria-activating potential of TND1128 in the present study. We expect TND1128 as a drug that rescues deteriorating neurons with aging or disease.
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Affiliation(s)
- Nanae Takahashi
- Department of Anesthesiology, Tokyo Medical University Hachioji Medical Center 1163 Tatemachi,Hachioji, Tokyo 193-0998, Japan.
| | - Norio Akaike
- Research Division for Clinical Pharmacology, Medical Corporation, Juryou Group, Kumamoto Kinoh Hospital, 6-8-1 Yamamuro, Kita-ku, Kumamoto 860-8518, Japan.
| | - Tomohisa Nagamatsu
- Laboratory of Curative Creation Study for Geriatric-diseases Prevention, Faculty of Pharmacological Sciences, Sojo University, 4-22-1 Ikeda, Nishi-ku, Kumamoto, 860-0082, Japan.
| | - Hiroyuki Uchino
- Department of Anesthesiology, Tokyo Medical University, 6-7-1 Nishishinjuku, Sinjuku-ku, Tokyo 160-0023, Japan.
| | - Yoshihisa Kudo
- Department of Anesthesiology, Tokyo Medical University Hachioji Medical Center 1163 Tatemachi,Hachioji, Tokyo 193-0998, Japan.
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Mamedova E, Dmytriyeva O, Rekling JC. Thyrotropin-releasing hormone induces Ca 2+ increase in a subset of vagal nodose ganglion neurons. Neuropeptides 2022; 94:102261. [PMID: 35704969 DOI: 10.1016/j.npep.2022.102261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Revised: 05/30/2022] [Accepted: 05/30/2022] [Indexed: 11/23/2022]
Abstract
Thyrotropin-releasing hormone (TRH) plays a central role in metabolic homeostasis, and single-cell sequencing has recently demonstrated that vagal sensory neurons in the nodose ganglion express thyrotropin-releasing hormone receptor 1 (TRHR1). Here, in situ hybridization validated the presence of TRHR1 in nodose ganglion (NG) neurons and immunohistochemistry showed that the receptor is expressed at the protein level. However, it has yet to be demonstrated whether TRHR1 is functionally active in NG neurons. Using NG explants transduced with a genetically encoded Ca2+ indicator (GECI), we show that TRH increases Ca2+ in a subset of NG neurons. TRH-induced Ca2+ transients were briefer compared to those induced by CCK-8, 2-Me-5-HT and ATP. Blocking Na+ channels with TTX or Na+ substitution did not affect the TRH-induced Ca2+ increase, but blocking Gq signaling with YM-254890 abolished the TRH-induced response. Field potential recordings from the vagus nerve in vitro showed an increase in response to TRH, suggesting that TRH signaling produces action potentials in NG neurons. These observations indicate that TRH activates a small group of NG neurons, involving Gq pathways, and we hypothesize that these neurons may play a role in gut-brain signaling.
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Affiliation(s)
- Esmira Mamedova
- Department of Neuroscience, University of Copenhagen, Panum - 24.4, Blegdamsvej 3, DK-2200 Copenhagen, Denmark
| | - Oksana Dmytriyeva
- Faculty of Health and Medical Sciences, Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
| | - Jens C Rekling
- Department of Neuroscience, University of Copenhagen, Panum - 24.4, Blegdamsvej 3, DK-2200 Copenhagen, Denmark.
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Shindo Y, Fujita K, Tanaka M, Fujio H, Hotta K, Oka K. Mechanical stimulus-evoked signal transduction between keratinocytes and sensory neurons via extracellular ATP. Biochem Biophys Res Commun 2021; 582:131-136. [PMID: 34710828 DOI: 10.1016/j.bbrc.2021.10.046] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Accepted: 10/20/2021] [Indexed: 12/25/2022]
Abstract
The skin is exposed to various external stimuli. Keratinocytes, which are the main cell type in the epidermis, interact with peripheral sensory neurons and modulate neuronal activity. Recent studies have revealed that keratinocytes play crucial roles in nociception, and that ATP is one of the main mediators of signal transduction from keratinocytes to sensory neurons. However, no quantitative cellular level analyses of ATP-mediated information flow from keratinocytes to sensory dorsal root ganglion (DRG) neurons have been conducted. In this study, we performed simultaneous imaging of cell surface ATP and intracellular Ca2+ signals using both iATPSnFR, a genetically encoded ATP probe localized to the outside of the cell membrane, and the Ca2+ probe, Fura-red. Upon mechanical stimulation of the keratinocyte with a glass needle, an increase in Ca2+ and ATP release were observed around the stimulated area, and these phenomena were positively correlated. In cultured DRG neurons and keratinocytes neighboring the stimulated keratinocyte, increased intracellular Ca2+ concentration and levels of cell surface ATP on the side closer to the stimulated cell were detected. The ratio of Ca2+ response to input ATP signal was significantly larger in DRG neurons than in keratinocytes. We found that DRG neurons were more sensitive to ATP than keratinocytes, and therefore, only DRG neurons responded to ATP at 1 μM or lower concentrations when in co-culture with keratinocytes. Moreover, signals caused by moderate mechanical stimulation of keratinocytes were transmitted predominantly to DRG neurons. These findings would be important in the further determination of the detailed mechanism of nociception in the epidermis.
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Affiliation(s)
- Yutaka Shindo
- Department of Bioscience and Informatics, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama, Kanagawa, 223-8522, Japan
| | - Keigo Fujita
- Department of Bioscience and Informatics, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama, Kanagawa, 223-8522, Japan
| | - Mari Tanaka
- Department of Bioscience and Informatics, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama, Kanagawa, 223-8522, Japan
| | - Hiroki Fujio
- Department of Bioscience and Informatics, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama, Kanagawa, 223-8522, Japan
| | - Kohji Hotta
- Department of Bioscience and Informatics, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama, Kanagawa, 223-8522, Japan
| | - Kotaro Oka
- Department of Bioscience and Informatics, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama, Kanagawa, 223-8522, Japan; Waseda Research Institute for Science and Engineering, Waseda University, 2-2 Wakamatsucho, Shinjuku-ku, Tokyo, 162-8480, Japan; Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung City, 80708, Taiwan.
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Amini M, Chang Y, Wissenbach U, Flockerzi V, Schlenstedt G, Beck A. Activity of the yeast vacuolar TRP channel TRPY1 is inhibited by Ca 2+-calmodulin binding. J Biol Chem 2021; 297:101126. [PMID: 34461097 PMCID: PMC8449268 DOI: 10.1016/j.jbc.2021.101126] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Revised: 08/23/2021] [Accepted: 08/23/2021] [Indexed: 02/07/2023] Open
Abstract
Transient receptor potential (TRP) cation channels, which are conserved across mammals, flies, fish, sea squirts, worms, and fungi, essentially contribute to cellular Ca2+ signaling. The activity of the unique TRP channel in yeast, TRP yeast channel 1 (TRPY1), relies on the vacuolar and cytoplasmic Ca2+ concentration. However, the mechanism(s) of Ca2+-dependent regulation of TRPY1 and possible contribution(s) of Ca2+-binding proteins are yet not well understood. Our results demonstrate a Ca2+-dependent binding of yeast calmodulin (CaM) to TRPY1. TRPY1 activity was increased in the cmd1–6 yeast strain, carrying a non–Ca2+-binding CaM mutant, compared with the parent strain expressing wt CaM (Cmd1). Expression of Cmd1 in cmd1–6 yeast rescued the wt phenotype. In addition, in human embryonic kidney 293 cells, hypertonic shock-induced TRPY1-dependent Ca2+ influx and Ca2+ release were increased by the CaM antagonist ophiobolin A. We found that coexpression of mammalian CaM impeded the activity of TRPY1 by reinforcing effects of endogenous CaM. Finally, inhibition of TRPY1 by Ca2+–CaM required the cytoplasmic amino acid stretch E33–Y92. In summary, our results show that TRPY1 is under inhibitory control of Ca2+–CaM and that mammalian CaM can replace yeast CaM for this inhibition. These findings add TRPY1 to the innumerable cellular proteins, which include a variety of ion channels, that use CaM as a constitutive or dissociable Ca2+-sensing subunit, and contribute to a better understanding of the modulatory mechanisms of Ca2+–CaM.
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Affiliation(s)
- Mahnaz Amini
- Experimentelle und Klinische Pharmakologie und Toxikologie/PZMS, Universität des Saarlandes, Homburg, Deutschland; Department of Medical Biochemistry and Molecular Biology/PZMS, Medical School, Saarland University, Homburg, Germany
| | - Yiming Chang
- Experimentelle und Klinische Pharmakologie und Toxikologie/PZMS, Universität des Saarlandes, Homburg, Deutschland; Department of Medical Biochemistry and Molecular Biology/PZMS, Medical School, Saarland University, Homburg, Germany
| | - Ulrich Wissenbach
- Experimentelle und Klinische Pharmakologie und Toxikologie/PZMS, Universität des Saarlandes, Homburg, Deutschland
| | - Veit Flockerzi
- Experimentelle und Klinische Pharmakologie und Toxikologie/PZMS, Universität des Saarlandes, Homburg, Deutschland
| | - Gabriel Schlenstedt
- Department of Medical Biochemistry and Molecular Biology/PZMS, Medical School, Saarland University, Homburg, Germany
| | - Andreas Beck
- Experimentelle und Klinische Pharmakologie und Toxikologie/PZMS, Universität des Saarlandes, Homburg, Deutschland.
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Shii F, Mang D, Kasubuchi M, Tsuneto K, Toyama T, Endo H, Sasaki K, Sato R. Ultrasensitive detection by maxillary palp neurons allows non-host recognition without consumption of harmful allelochemicals. J Insect Physiol 2021; 132:104263. [PMID: 34052304 DOI: 10.1016/j.jinsphys.2021.104263] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2021] [Revised: 05/25/2021] [Accepted: 05/25/2021] [Indexed: 06/12/2023]
Abstract
Most lepidopteran insect larvae exhibit stepwise feeding behaviors, such as palpation using the maxillary palps (MPs) followed by test biting and persistent biting. However, the purpose of palpation has been unclear. In particular, nothing is known about the neurons in the MP and their mode of recognition of undesired plants, although such neurons have been suggested to exist. In this study, we used larvae of the stenophagous insect Bombyx mori and compared the roles of palpation and test biting in the selection of feeding behavior. When the larvae were given non-host plant leaves, they did not initiate test biting, indicating that non-host plant leaves were recognized via palpation without biting, and that this behavior resulted in a lack of persistent biting, as the leaves were judged non-suitable for consumption. Surface extracts of inedible leaves significantly suppressed test biting of mulberry leaves, a host plant of B. mori, suggesting that secondary metabolites on the leaf surface of inedible leaves function as test biting suppressors, even when another conditions are suitable for test biting. The allelochemical coumarin, which is found in the inedible leaves of cherry, Cerasus speciosa, significantly suppressed test biting of mulberry leaves, suggesting that coumarin is a possible deterrent to the eating of cherry leaves. Using the electrophysiological method of tip recording and a leaf-surface extract as the test material, leaf-surface compound-responsive neurons were identified in the MP. In addition, several neurons that respond to coumarin in the attomolar range were identified, suggesting that the larvae use ultrasensitive neurons in the MP to recognize inedible leaves. In the HEK293T cell heterologous expression system, the B. mori gustatory receptors BmGr53 and BmGr19, which were previously found to be expressed in the MP and to respond to coumarin in the attomolar range, responded to a leaf-surface extract of C. speciosa, suggesting that these receptors may be present on the inedible-leaf-recognizing neurons of the MP. These findings suggest that ultrasensitive plant secondary metabolite-recognizing neurons in the MP allow for the recognition of non-host plants via palpation without risking damage caused by ingesting harmful allelochemicals.
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Affiliation(s)
- Fumika Shii
- Graduate School of Bio-Application and Systems Engineering, Tokyo University of Agriculture and Technology, Naka-cho 2-24-16, Koganei, Tokyo 184-8588, Japan
| | - Dingze Mang
- Graduate School of Bio-Application and Systems Engineering, Tokyo University of Agriculture and Technology, Naka-cho 2-24-16, Koganei, Tokyo 184-8588, Japan
| | - Mayu Kasubuchi
- Graduate School of Bio-Application and Systems Engineering, Tokyo University of Agriculture and Technology, Naka-cho 2-24-16, Koganei, Tokyo 184-8588, Japan
| | - Kana Tsuneto
- Graduate School of Bio-Application and Systems Engineering, Tokyo University of Agriculture and Technology, Naka-cho 2-24-16, Koganei, Tokyo 184-8588, Japan
| | - Tomoko Toyama
- Graduate School of Bio-Application and Systems Engineering, Tokyo University of Agriculture and Technology, Naka-cho 2-24-16, Koganei, Tokyo 184-8588, Japan
| | - Haruka Endo
- Graduate School of Bio-Application and Systems Engineering, Tokyo University of Agriculture and Technology, Naka-cho 2-24-16, Koganei, Tokyo 184-8588, Japan
| | - Ken Sasaki
- Graduate School of Agriculture, Tamagawa University, Tamagawagakuen 6-1-1, Machida, Tokyo 194-8610, Japan
| | - Ryoichi Sato
- Graduate School of Bio-Application and Systems Engineering, Tokyo University of Agriculture and Technology, Naka-cho 2-24-16, Koganei, Tokyo 184-8588, Japan.
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Sun B, Yao J, Chen AW, Estillore JP, Wang R, Back TG, Chen SRW. Genetically and pharmacologically limiting RyR2 open time prevents neuronal hyperactivity of hippocampal CA1 neurons in brain slices of 5xFAD mice. Neurosci Lett 2021; 758:136011. [PMID: 34090936 DOI: 10.1016/j.neulet.2021.136011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Revised: 03/19/2021] [Accepted: 05/28/2021] [Indexed: 12/11/2022]
Abstract
Neuronal hyperactivity is an early, common manifestation of Alzheimer's disease (AD), and is believed to drive AD progression. Neuronal hyperactivity in the form of baseline activity (or spontaneous Ca2+ transients) has consistently been demonstrated in mouse models of AD using two-photon in vivo Ca2+ imaging of cortical or hippocampal neurons in anesthetized animals. Notably, these AD-related spontaneous Ca2+ transients were hardly detected in acute hippocampal slices, probably due to neuronal damage during brain slicing. To better preserve neuronal activity, we employed the N-methyl-D-glucamine (NMDG) protective brain slicing protocol. We performed confocal in vitro Ca2+ imaging of hippocampal CA1 neurons in optimized hippocampal slices. Consistent with previous in vivo studies, our in vitro studies using optimized brain slices also showed that limiting the open duration of the ryanodine receptor 2 (RyR2) by the RyR2 mutation E4872Q or by the R-carvedilol enantiomer prevented and rescued neuronal hyperactivity of hippocampal CA1 neurons from 5xFAD mice. Thus, genetically and pharmacologically limiting RyR2 open time prevented and rescued AD-related neuronal hyperactivity in vitro in optimized brain slices in the absence of anesthetics' influence. Our data also suggest that the NMDG protective brain slicing preparation offers an alternative means to study neuronal hyperactivity of various cell types in different brain regions, especially in regions that are not readily accessible to two-photon in vivo Ca2+ imaging.
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Affiliation(s)
- Bo Sun
- Libin Cardiovascular Institute, Department of Physiology and Pharmacology, University of Calgary, Calgary, AB, Canada
| | - Jinjing Yao
- Libin Cardiovascular Institute, Department of Physiology and Pharmacology, University of Calgary, Calgary, AB, Canada
| | - Alexander W Chen
- Libin Cardiovascular Institute, Department of Physiology and Pharmacology, University of Calgary, Calgary, AB, Canada
| | - John Paul Estillore
- Libin Cardiovascular Institute, Department of Physiology and Pharmacology, University of Calgary, Calgary, AB, Canada
| | - Ruiwu Wang
- Libin Cardiovascular Institute, Department of Physiology and Pharmacology, University of Calgary, Calgary, AB, Canada
| | - Thomas G Back
- Department of Chemistry, University of Calgary, Calgary, AB, Canada
| | - S R Wayne Chen
- Libin Cardiovascular Institute, Department of Physiology and Pharmacology, University of Calgary, Calgary, AB, Canada; Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada.
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Izumisawa Y, Ito K, Sugita K, Arai T, Kokudo H, Kitamura N, Shibuya I. Mechanisms of GABA-mediated inhibition of the angiotensin II-induced cytosolic Ca 2+ increase in rat subfornical organ neurons. Brain Res 2021; 1763:147451. [PMID: 33773979 DOI: 10.1016/j.brainres.2021.147451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Revised: 03/18/2021] [Accepted: 03/22/2021] [Indexed: 10/21/2022]
Abstract
Neurons in the subfornical organ (SFO) sense both neurotransmitters and circulating humoral factors such as angiotensin II (AII) and atrial natriuretic peptide (ANP), and regulate multiple physiological functions including drinking behavior. We recently reported that AII at nanomolar concentrations induced a persistent [Ca2+]i increase in acutely dissociated SFO neurons and that this effect of AII was reversibly inhibited by GABA. In the present study, we studied the inhibitory mechanism of GABA using Ca2+ imaging and patch-clamp electrophysiology. The AII-induced persistent [Ca2+]i increase was inhibited by GABA in more than 90% of AII-responsive neurons and by other two SFO inhibitory ligands, ANP and galanin, in about 60 and 30% of neurons respectively. The inhibition by GABA was mimicked by the GABAA and GABAB receptor agonists muscimol and baclofen. The involvement of both GABA receptor subtypes was confirmed by reversal of the GABA-mediated inhibition only when the GABAA and GABAB receptors antagonists bicuculline methiodide and CGP55845 were both present. The GABAB agonist baclofen rapidly and reversibly inhibited voltage-gated Ca2+ channel (VGCC) currents recorded in response to depolarizing pulses in voltage-clamp electrophysiology using Ba2+ as a charge carrier (IBa). Baclofen inhibition of IBa was antagonized by CGP55845, confirming GABAB receptor involvement; was reduced by N-ethylmaleimide, suggesting downstream Gi-mediated actions; and was partially removed by a large prepulse, indicating voltage-dependency. The magnitude of IBa inhibition by baclofen was reduced by the application of selective blockers for N-, P/Q-, and L-type VGCCs (ω-conotoxin GVIA, ω-agatoxin IVA, and nifedipine respectively). Overall, our study indicates that GABA inhibition of the AII-induced [Ca2+]i increase is mediated by both GABAA and GABAB receptors, and that GABAB receptors associated with Gi proteins suppress Ca2+ entry through VGCCs in SFO neurons.
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Affiliation(s)
- Yu Izumisawa
- Department of Veterinary Physiology, Faculty of Agriculture, Tottori University, Japan
| | - Kenji Ito
- Department of Veterinary Physiology, Faculty of Agriculture, Tottori University, Japan
| | - Keisuke Sugita
- Department of Veterinary Physiology, Faculty of Agriculture, Tottori University, Japan
| | - Tazuyo Arai
- Department of Veterinary Physiology, Faculty of Agriculture, Tottori University, Japan
| | - Hina Kokudo
- Department of Veterinary Physiology, Faculty of Agriculture, Tottori University, Japan
| | - Naoki Kitamura
- Department of Veterinary Physiology, Faculty of Agriculture, Tottori University, Japan
| | - Izumi Shibuya
- Department of Veterinary Physiology, Faculty of Agriculture, Tottori University, Japan.
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Bornschein G, Eilers J, Schmidt H. Neocortical High Probability Release Sites Are Formed by Distinct Ca 2+ Channel-to-Release Sensor Topographies during Development. Cell Rep 2020; 28:1410-1418.e4. [PMID: 31390556 DOI: 10.1016/j.celrep.2019.07.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Revised: 05/29/2019] [Accepted: 06/28/2019] [Indexed: 01/10/2023] Open
Abstract
Coupling distances between Ca2+ channels and release sensors regulate vesicular release probability (pv). Tight coupling is thought to provide a framework for high pv and loose coupling for high plasticity at low pv. At synapses investigated during development, coupling distances decrease, thereby increasing pv and transmission fidelity. We find that neocortical high-fidelity synapses deviate from these rules. Paired recordings from pyramidal neurons with "slow" and "fast" Ca2+ chelators combined with experimentally constrained simulations suggest that coupling tightens significantly during development. However, fluctuation analysis revealed that neither pv (∼0.63) nor the number of release sites (∼8) changes concomitantly. Moreover, the amplitude and time course of presynaptic Ca2+ transients are not different between age groups. These results are explained by high-pv release sites with Ca2+ microdomains in young synapses and nanodomains in mature synapses. Thus, at neocortical synapses, a developmental reorganization of the active zone leaves pv unaffected, emphasizing developmental and functional synaptic diversity.
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Affiliation(s)
- Grit Bornschein
- Carl-Ludwig-Institute for Physiology, Medical Faculty, University of Leipzig, Liebigstrasse 27a, 04103 Leipzig, Germany.
| | - Jens Eilers
- Carl-Ludwig-Institute for Physiology, Medical Faculty, University of Leipzig, Liebigstrasse 27a, 04103 Leipzig, Germany
| | - Hartmut Schmidt
- Carl-Ludwig-Institute for Physiology, Medical Faculty, University of Leipzig, Liebigstrasse 27a, 04103 Leipzig, Germany.
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Otomo K, Goto A, Yamanaka Y, Hori T, Nakayama H, Nemoto T. High-peak-power 918-nm laser light source based two-photon spinning-disk microscopy for green fluorophores. Biochem Biophys Res Commun 2020; 529:238-242. [PMID: 32703417 DOI: 10.1016/j.bbrc.2020.05.213] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Accepted: 05/29/2020] [Indexed: 11/26/2022]
Abstract
High-speed imaging of living specimen was performed using two-photon microscopy equipped with a spinning-disk scanning unit. Typically, a high-peak-power laser light source is needed to simultaneously induce two-photon excitation processes at several hundred focal points, generating the limitations of excitable fluorophores. Therefore, a high-peak-power neodymium-based 918-nm laser light source was used for intravital imaging of the most popular fluorophores, green fluorescent proteins. As a result, the proposed system obtained approximately 30 times brighter fluorescent signal than that obtained using a conventional mode-locked titanium:sapphire laser light source. Furthermore, the system visualized four-dimensional (xyz-t) calcium responses of pancreatic acinar cells agonist stimulations in the living G-CaMP7-expressing mouse with 60 million μm3 volume.
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Affiliation(s)
- Kohei Otomo
- Exploratory Research Center on Life and Living Systems, National Institutes of Natural Sciences, 5-1, Higashiyama, Myodaiji, Okazaki, 444-8787, Japan; National Institute for Physiological Sciences, 5-1, Higashiyama, Myodaiji, Okazaki, 444-8787, Japan; Graduate School of Advanced Studies Sciences (SOKENDAI), 5-1, Higashiyama, Myodaiji, Okazaki, 444-8787, Japan; Research Institute for Electronic Science, Hokkaido University, Kita 20 Nishi 10, Kita, Sapporo, 001-0020, Japan; Graduate School of Information Science and Technology, Hokkaido University, Kita 14 Nishi 9, Kita, Sapporo, 001-0014, Japan.
| | - Ai Goto
- Research Institute for Electronic Science, Hokkaido University, Kita 20 Nishi 10, Kita, Sapporo, 001-0020, Japan; Graduate School of Information Science and Technology, Hokkaido University, Kita 14 Nishi 9, Kita, Sapporo, 001-0014, Japan
| | - Yumi Yamanaka
- Research Institute for Electronic Science, Hokkaido University, Kita 20 Nishi 10, Kita, Sapporo, 001-0020, Japan; Graduate School of Information Science and Technology, Hokkaido University, Kita 14 Nishi 9, Kita, Sapporo, 001-0014, Japan
| | - Takashi Hori
- IMRA America, Inc., 1044 Woodridge Avenue, Ann Arbor, MI, 48105, USA
| | - Hiroshi Nakayama
- Yokogawa Electric Corporation, 2-3 Hokuyoudai, Kanazawa, 920-0177, Japan
| | - Tomomi Nemoto
- Exploratory Research Center on Life and Living Systems, National Institutes of Natural Sciences, 5-1, Higashiyama, Myodaiji, Okazaki, 444-8787, Japan; National Institute for Physiological Sciences, 5-1, Higashiyama, Myodaiji, Okazaki, 444-8787, Japan; Graduate School of Advanced Studies Sciences (SOKENDAI), 5-1, Higashiyama, Myodaiji, Okazaki, 444-8787, Japan; Research Institute for Electronic Science, Hokkaido University, Kita 20 Nishi 10, Kita, Sapporo, 001-0020, Japan; Graduate School of Information Science and Technology, Hokkaido University, Kita 14 Nishi 9, Kita, Sapporo, 001-0014, Japan
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11
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Bachmann SB, Gsponer D, Montoya-Zegarra JA, Schneider M, Scholkmann F, Tacconi C, Noerrelykke SF, Proulx ST, Detmar M. A Distinct Role of the Autonomic Nervous System in Modulating the Function of Lymphatic Vessels under Physiological and Tumor-Draining Conditions. Cell Rep 2020; 27:3305-3314.e13. [PMID: 31189113 PMCID: PMC6581737 DOI: 10.1016/j.celrep.2019.05.050] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Revised: 02/22/2019] [Accepted: 05/15/2019] [Indexed: 11/19/2022] Open
Abstract
Lymphatic vessels (LVs) are important in the regulation of tissue fluid homeostasis and the pathogenesis of tumor progression. We investigated the innervation of LVs and the response to agonists and antagonists of the autonomic nervous system in vivo. While skin-draining collecting LVs express muscarinic, α1- and β2-adrenergic receptors on lymphatic endothelial cells and smooth muscle cells, intestinal lacteals express only β-adrenergic receptors and muscarinic receptors on their smooth muscle cells. Quantitative in vivo near-infrared imaging of the exposed flank-collecting LV revealed that muscarinic and α1-adrenergic agonists increased LV contractility, whereas activation of β2-adrenergic receptors inhibited contractility and initiated nitric oxide (NO)-dependent vasodilation. Tumor-draining LVs were expanded and showed a higher innervation density and contractility that was reduced by treatment with atropine, phentolamine, and, most potently, isoproterenol. These findings likely have clinical implications given the impact of lymphatic fluid drainage on intratumoral fluid pressure and thus drug delivery. Murine lymphatic vessels are innervated in an organ-specific manner α1-adrenergic and muscarinic agents enhance lymphatic contractility in vivo β2-adrenergic agents reduce lymphatic contractility Tumor-draining lymphatic vessels have increased innervation and contractility
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Affiliation(s)
- Samia B Bachmann
- Institute of Pharmaceutical Sciences, Swiss Federal Institute of Technology, ETH Zurich, 8093 Zurich, Switzerland
| | - Denise Gsponer
- Institute of Pharmaceutical Sciences, Swiss Federal Institute of Technology, ETH Zurich, 8093 Zurich, Switzerland
| | | | - Martin Schneider
- Institute for Biomedical Engineering, ETH Zurich and University of Zurich, 8093 Zurich, Switzerland
| | - Felix Scholkmann
- Biomedical Optics Research Laboratory, Department of Neonatology, University Hospital Zurich, University of Zurich, 8091 Zurich, Switzerland
| | - Carlotta Tacconi
- Institute of Pharmaceutical Sciences, Swiss Federal Institute of Technology, ETH Zurich, 8093 Zurich, Switzerland
| | - Simon F Noerrelykke
- ScopeM, Swiss Federal Institute of Technology, ETH Zurich, 8093 Zurich, Switzerland
| | - Steven T Proulx
- Institute of Pharmaceutical Sciences, Swiss Federal Institute of Technology, ETH Zurich, 8093 Zurich, Switzerland
| | - Michael Detmar
- Institute of Pharmaceutical Sciences, Swiss Federal Institute of Technology, ETH Zurich, 8093 Zurich, Switzerland.
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12
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Kawano H, Mitchell SB, Koh JY, Goodman KM, Harata NC. Calcium-induced calcium release in noradrenergic neurons of the locus coeruleus. Brain Res 2020; 1729:146627. [PMID: 31883849 DOI: 10.1016/j.brainres.2019.146627] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Revised: 12/19/2019] [Accepted: 12/24/2019] [Indexed: 12/11/2022]
Abstract
The locus coeruleus (LC) is a nucleus within the brainstem that consists of norepinephrine-releasing neurons. It is involved in broad processes including cognitive and emotional functions. Understanding the mechanisms that control the excitability of LC neurons is important because they innervate widespread brain regions. One of the key regulators is cytosolic calcium concentration ([Ca2+]c), the increases in which can be amplified by calcium-induced calcium release (CICR) from intracellular calcium stores. Although the electrical activities of LC neurons are regulated by changes in [Ca2+]c, the extent of CICR involvement in this regulation has remained unclear. Here we show that CICR hyperpolarizes acutely dissociated LC neurons of the rat and demonstrate the underlying pathway. When CICR was activated by extracellular application of 10 mM caffeine, LC neurons were hyperpolarized in the current-clamp mode of patch-clamp recording, and the majority of neurons showed an outward current in the voltage-clamp mode. This outward current was accompanied by increased membrane conductance, and its reversal potential was close to the K+ equilibrium potential, indicating that it is mediated by opening of K+ channels. The outward current was generated in the absence of extracellular calcium and was blocked when the calcium stores were inhibited by applying ryanodine. Pharmacological blockers indicated that it was mediated by Ca2+-activated K+ channels of the non-small conductance type. The application of caffeine increased [Ca2+]c, as visualized by fluorescence microscopy. These findings show CICR suppresses LC neuronal activity, and indicate its dynamic role in modulating the LC-mediated noradrenergic tone in the brain.
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Affiliation(s)
- Hiroyuki Kawano
- Department of Molecular Physiology and Biophysics, University of Iowa Carver College of Medicine, Iowa City, IA, USA
| | - Sara B Mitchell
- Department of Molecular Physiology and Biophysics, University of Iowa Carver College of Medicine, Iowa City, IA, USA
| | - Jin-Young Koh
- Department of Molecular Physiology and Biophysics, University of Iowa Carver College of Medicine, Iowa City, IA, USA; Molecular Otolaryngology and Renal Research Laboratories, Department of Otolaryngology-Head and Neck Surgery, University of Iowa Carver College of Medicine, Iowa City, IA, USA; Department of Biomedical Engineering, University of Iowa College of Engineering, Iowa City, IA, USA
| | - Kirsty M Goodman
- Department of Molecular Physiology and Biophysics, University of Iowa Carver College of Medicine, Iowa City, IA, USA; Department of Biology & Biochemistry, University of Bath, Bath, UK
| | - N Charles Harata
- Department of Molecular Physiology and Biophysics, University of Iowa Carver College of Medicine, Iowa City, IA, USA.
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13
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Swaminathan D, Dickinson GD, Demuro A, Parker I. Noise analysis of cytosolic calcium image data. Cell Calcium 2019; 86:102152. [PMID: 31918030 DOI: 10.1016/j.ceca.2019.102152] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Revised: 12/15/2019] [Accepted: 12/16/2019] [Indexed: 11/28/2022]
Abstract
Cellular Ca2+ signals are often constrained to cytosolic micro- or nano-domains where stochastic openings of Ca2+ channels cause large fluctuations in local Ca2+ concentration (Ca2+ 'noise'). With the advent of TIRF microscopy to image the fluorescence of Ca2+-sensitive probes from attoliter volumes it has become possible to directly monitor these signals, which closely track the gating of plasmalemmal and ER Ca2+-permeable channels. Nevertheless, it is likely that many physiologically important Ca2+ signals are too small to resolve as discrete events in fluorescence recordings. By analogy with noise analysis of electrophysiological data, we explore here the use of statistical approaches to detect and analyze such Ca2+ noise in images obtained using Ca2+-sensitive indicator dyes. We describe two techniques - power spectrum analysis and spatio-temporal correlation - and demonstrate that both effectively identify discrete, spatially localized calcium release events (Ca2+ puffs). Moreover, we show they are able to detect localized noise fluctuations in a case where discrete events cannot directly be resolved.
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Affiliation(s)
- Divya Swaminathan
- Department of Neurobiology & Behavior, University of California, Irvine, CA92697, USA.
| | - George D Dickinson
- Department of Neurobiology & Behavior, University of California, Irvine, CA92697, USA
| | - Angelo Demuro
- Department of Neurobiology & Behavior, University of California, Irvine, CA92697, USA
| | - Ian Parker
- Department of Neurobiology & Behavior, University of California, Irvine, CA92697, USA; Department of Physiology & Biophysics, University of California, Irvine, CA92697, USA
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14
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Grund T, Tang Y, Benusiglio D, Althammer F, Probst S, Oppenländer L, Neumann ID, Grinevich V. Chemogenetic activation of oxytocin neurons: Temporal dynamics, hormonal release, and behavioral consequences. Psychoneuroendocrinology 2019; 106:77-84. [PMID: 30954921 DOI: 10.1016/j.psyneuen.2019.03.019] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Revised: 02/15/2019] [Accepted: 03/20/2019] [Indexed: 01/17/2023]
Abstract
Chemogenetics provides cell type-specific remote control of neuronal activity. Here, we describe the application of chemogenetics used to specifically activate oxytocin (OT) neurons as representatives of a unique class of neuroendocrine cells. We injected recombinant adeno-associated vectors, driving the stimulatory subunit hM3Dq of a modified human muscarinic receptor into the rat hypothalamus to achieve cell type-specific expression in OT neurons. As chemogenetic activation of OT neurons has not been reported, we provide systematic analysis of the temporal dynamics of OT neuronal responses in vivo by monitoring calcium fluctuations in OT neurons, and intracerebral as well as peripheral release of OT. We further provide evidence for the efficiency of chemogenetic manipulation at behavioral levels, demonstrating that evoked activation of OT neurons leads to social motivation and anxiolysis. Altogether, our results will be profitable for researchers working on the physiology of neuroendocrine systems, peptidergic modulation of behaviors and translational psychiatry.
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Affiliation(s)
- Thomas Grund
- Department of Behavioral and Molecular Neurobiology, Regensburg Center of Neuroscience, University of Regensburg, 93040 Regensburg, Germany
| | - Yan Tang
- Division of Neuropeptides (V078), German Cancer Research Center and Central Institute of Mental Health, University of Heidelberg, 69120 Heidelberg, Germany
| | - Diego Benusiglio
- Division of Neuropeptides (V078), German Cancer Research Center and Central Institute of Mental Health, University of Heidelberg, 69120 Heidelberg, Germany
| | - Ferdinand Althammer
- Division of Neuropeptides (V078), German Cancer Research Center and Central Institute of Mental Health, University of Heidelberg, 69120 Heidelberg, Germany
| | - Sophia Probst
- Department of Behavioral and Molecular Neurobiology, Regensburg Center of Neuroscience, University of Regensburg, 93040 Regensburg, Germany
| | - Lena Oppenländer
- Department of Behavioral and Molecular Neurobiology, Regensburg Center of Neuroscience, University of Regensburg, 93040 Regensburg, Germany
| | - Inga D Neumann
- Department of Behavioral and Molecular Neurobiology, Regensburg Center of Neuroscience, University of Regensburg, 93040 Regensburg, Germany.
| | - Valery Grinevich
- Division of Neuropeptides (V078), German Cancer Research Center and Central Institute of Mental Health, University of Heidelberg, 69120 Heidelberg, Germany.
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15
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Izumisawa Y, Tanaka-Yamamoto K, Ciriello J, Kitamura N, Shibuya I. Persistent cytosolic Ca 2+ increase induced by angiotensin II at nanomolar concentrations in acutely dissociated subfornical organ (SFO) neurons of rats. Brain Res 2019; 1718:137-147. [PMID: 31085158 DOI: 10.1016/j.brainres.2019.05.014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Revised: 04/23/2019] [Accepted: 05/11/2019] [Indexed: 10/26/2022]
Abstract
It is known that angiotensin II (AII) is sensed by subfornical organ (SFO) to induce drinking behaviors and autonomic changes. AII at picomolar concentrations have been shown to induce Ca2+ oscillations and increase in the amplitude and frequency of spontaneous Ca2+ oscillations in SFO neurons. The present study was conducted to examine effects of nanomolar concentrations of AII using the Fura-2 Ca2+-imaging technique in acutely dissociated SFO neurons. AII at nanomolar concentrations induced an initial [Ca2+]i peak followed by a persistent [Ca2+]i increase lasting for longer than 1 hour. By contrast, [Ca2+]i responses to 50 mM K+, maximally effective concentrations of glutamate, carbachol, and vasopressin, and AII given at picomolar concentrations returned to the basal level within 20 min. The AII-induced [Ca2+]i increase was blocked by the AT1 antagonist losartan. However, losartan had no effect when added during the persistent phase. The persistent phase was suppressed by extracellular Ca2+ removal, significantly inhibited by blockers of L and P/Q type Ca2+ channels , but unaffected by inhibition of Ca2+ store Ca2+ ATPase. The persistent phase was reversibly suppressed by GABA and inhibited by CaMK and PKC inhibitors. These results suggest that the persistent [Ca2+]i increase evoked by nanomolar concentrations of AII is initiated by AT1 receptor activation and maintained by Ca2+ entry mechanisms in part through L and P/Q type Ca2+ channels, and that CaMK and PKC are involved in this process. The persistent [Ca2+]i increase induced by AII at high pathophysiological levels may have a significant role in altering SFO neuronal functions.
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Affiliation(s)
- Yu Izumisawa
- Department of Veterinary Physiology, Faculty of Agriculture, Tottori University, Tottori 680-0945, Japan
| | - Keiko Tanaka-Yamamoto
- Center for Functional Connectomics, Korea Institute of Science and Technology, Seoul 136-791, Republic of Korea
| | - John Ciriello
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario N6A 5C1, Canada
| | - Naoki Kitamura
- Department of Veterinary Physiology, Faculty of Agriculture, Tottori University, Tottori 680-0945, Japan
| | - Izumi Shibuya
- Department of Veterinary Physiology, Faculty of Agriculture, Tottori University, Tottori 680-0945, Japan.
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16
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Weisenburger S, Tejera F, Demas J, Chen B, Manley J, Sparks FT, Martínez Traub F, Daigle T, Zeng H, Losonczy A, Vaziri A. Volumetric Ca 2+ Imaging in the Mouse Brain Using Hybrid Multiplexed Sculpted Light Microscopy. Cell 2019; 177:1050-1066.e14. [PMID: 30982596 DOI: 10.1016/j.cell.2019.03.011] [Citation(s) in RCA: 94] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Revised: 12/19/2018] [Accepted: 03/04/2019] [Indexed: 01/07/2023]
Abstract
Calcium imaging using two-photon scanning microscopy has become an essential tool in neuroscience. However, in its typical implementation, the tradeoffs between fields of view, acquisition speeds, and depth restrictions in scattering brain tissue pose severe limitations. Here, using an integrated systems-wide optimization approach combined with multiple technical innovations, we introduce a new design paradigm for optical microscopy based on maximizing biological information while maintaining the fidelity of obtained neuron signals. Our modular design utilizes hybrid multi-photon acquisition and allows volumetric recording of neuroactivity at single-cell resolution within up to 1 × 1 × 1.22 mm volumes at up to 17 Hz in awake behaving mice. We establish the capabilities and potential of the different configurations of our imaging system at depth and across brain regions by applying it to in vivo recording of up to 12,000 neurons in mouse auditory cortex, posterior parietal cortex, and hippocampus.
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Affiliation(s)
- Siegfried Weisenburger
- Laboratory of Neurotechnology and Biophysics, The Rockefeller University, New York, NY, USA
| | - Frank Tejera
- Laboratory of Neurotechnology and Biophysics, The Rockefeller University, New York, NY, USA
| | - Jeffrey Demas
- Laboratory of Neurotechnology and Biophysics, The Rockefeller University, New York, NY, USA
| | - Brandon Chen
- Laboratory of Neurotechnology and Biophysics, The Rockefeller University, New York, NY, USA
| | - Jason Manley
- Laboratory of Neurotechnology and Biophysics, The Rockefeller University, New York, NY, USA
| | - Fraser T Sparks
- Department of Neuroscience, Columbia University, New York, NY, USA; Mortimer B. Zuckerman Mind Brain Behavior Institute, Columbia University, New York, NY, USA
| | | | - Tanya Daigle
- Allen Institute for Brain Science, Seattle, WA, USA
| | - Hongkui Zeng
- Allen Institute for Brain Science, Seattle, WA, USA
| | - Attila Losonczy
- Department of Neuroscience, Columbia University, New York, NY, USA; The Kavli Institute for Brain Science, Columbia University, New York, NY, USA; Mortimer B. Zuckerman Mind Brain Behavior Institute, Columbia University, New York, NY, USA
| | - Alipasha Vaziri
- Laboratory of Neurotechnology and Biophysics, The Rockefeller University, New York, NY, USA; Research Institute of Molecular Pathology, Vienna, Austria; The Kavli Neural Systems Institute, The Rockefeller University, New York, NY, USA.
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17
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Taylor BK, Sinha GP, Donahue RR, Grachen CM, Morón JA, Doolen S. Opioid receptors inhibit the spinal AMPA receptor Ca 2+ permeability that mediates latent pain sensitization. Exp Neurol 2019; 314:58-66. [PMID: 30660616 DOI: 10.1016/j.expneurol.2019.01.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Revised: 12/24/2018] [Accepted: 01/05/2019] [Indexed: 01/02/2023]
Abstract
Acute inflammation induces sensitization of nociceptive neurons and triggers the accumulation of calcium permeable (CP) α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptors (AMPARs) in the dorsal horn of the spinal cord. This coincides with behavioral signs of acute inflammatory pain, but whether CP-AMPARs contribute to chronic pain remains unclear. To evaluate this question, we first constructed current-voltage (IV) curves of C-fiber stimulus-evoked, AMPAR-mediated EPSCs in lamina II to test for inward rectification, a key characteristic of CP-AMPARs. We found that the intraplantar injection of complete Freund's adjuvant (CFA) induced an inward rectification at 3 d that persisted to 21 d after injury. Furthermore, the CP- AMPAR antagonist IEM-1460 (50 μM) inhibited AMPAR-evoked Ca2+ transients 21d after injury but had no effect in uninflamed mice. We then used a model of long-lasting vulnerability for chronic pain that is determined by the balance between latent central sensitization (LCS) and mu opioid receptor constitutive activity (MORCA). When administered 21 d after the intraplantar injection of CFA, intrathecal administration of the MORCA inverse agonist naltrexone (NTX, 1 μg, i.t.) reinstated mechanical hypersensitivity, and superfusion of spinal cord slices with NTX (10 μM) increased the peak amplitude of AMPAR-evoked Ca2+ transients in lamina II neurons. The CP-AMPAR antagonist naspm (0-10 nmol, i.t.) inhibited these NTX-induced increases in mechanical hypersensitivity. NTX had no effect in uninflamed mice. Subsequent western blot analysis of the postsynaptic density membrane fraction from lumbar dorsal horn revealed that CFA increased GluA1 expression at 2 d and GluA4 expression at both 2 and 21 d post-injury, indicating that not just the GluA1 subunit, but also the GluA4 subunit, contributes to the expression of CP-AMPARs and synaptic strength during hyperalgesia. GluA2 expression increased at 21 d, an unexpected result that requires further study. We conclude that after tissue injury, dorsal horn AMPARs retain a Ca2+ permeability that underlies LCS. Because of their effectiveness in reducing naltrexone-induced reinstatement of hyperalgesia and potentiation of AMPAR-evoked Ca2+ signals, CP-AMPAR inhibitors are a promising class of agents for the treatment of chronic inflammatory pain.
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Affiliation(s)
- Bradley K Taylor
- Department of Anesthesiology, Pittsburgh Center for Pain Research, University of Pittsburgh School of Medicine, 200 Lothrop St. Pittsburgh, PA 15213, USA; Department of Physiology, University of Kentucky School of Medicine, 800 Rose, St. Lexington, KY 40536-0298, USA.
| | - Ghanshyam P Sinha
- Department of Anesthesiology, Pittsburgh Center for Pain Research, University of Pittsburgh School of Medicine, 200 Lothrop St. Pittsburgh, PA 15213, USA; Department of Physiology, University of Kentucky School of Medicine, 800 Rose, St. Lexington, KY 40536-0298, USA.
| | - Renee R Donahue
- Department of Physiology, University of Kentucky School of Medicine, 800 Rose, St. Lexington, KY 40536-0298, USA.
| | - Carolyn M Grachen
- Department of Anesthesiology, Pittsburgh Center for Pain Research, University of Pittsburgh School of Medicine, 200 Lothrop St. Pittsburgh, PA 15213, USA; Department of Physiology, University of Kentucky School of Medicine, 800 Rose, St. Lexington, KY 40536-0298, USA.
| | - Jose A Morón
- Department of Anesthesiology, Washington University Pain Center, Washington University School of Medicine, 600 South Euclid, St Louis, MO 63110, USA.
| | - Suzanne Doolen
- Department of Anesthesiology, Pittsburgh Center for Pain Research, University of Pittsburgh School of Medicine, 200 Lothrop St. Pittsburgh, PA 15213, USA; Department of Physiology, University of Kentucky School of Medicine, 800 Rose, St. Lexington, KY 40536-0298, USA.
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18
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Berekméri E, Deák O, Téglás T, Sághy É, Horváth T, Aller M, Fekete Á, Köles L, Zelles T. Targeted single-cell electroporation loading of Ca 2+ indicators in the mature hemicochlea preparation. Hear Res 2018; 371:75-86. [PMID: 30504093 DOI: 10.1016/j.heares.2018.11.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Revised: 10/30/2018] [Accepted: 11/07/2018] [Indexed: 10/27/2022]
Abstract
Ca2+ is an important intracellular messenger and regulator in both physiological and pathophysiological mechanisms in the hearing organ. Investigation of cellular Ca2+ homeostasis in the mature cochlea is hampered by the special anatomy and high vulnerability of the organ. A quick, straightforward and reliable Ca2+ imaging method with high spatial and temporal resolution in the mature organ of Corti is missing. Cell cultures or isolated cells do not preserve the special microenvironment and intercellular communication, while cochlear explants are excised from only a restricted portion of the organ of Corti and usually from neonatal pre-hearing murines. The hemicochlea, prepared from hearing mice allows tonotopic experimental approach on the radial perspective in the basal, middle and apical turns of the organ. We used the preparation recently for functional imaging in supporting cells of the organ of Corti after bulk loading of the Ca2+ indicator. However, bulk loading takes long time, is variable and non-selective, and causes the accumulation of the indicator in the extracellular space. In this study we show the improved labeling of supporting cells of the organ of Corti by targeted single-cell electroporation in mature mouse hemicochlea. Single-cell electroporation proved to be a reliable way of reducing the duration and variability of loading and allowed subcellular Ca2+ imaging by increasing the signal-to-noise ratio, while cell viability was retained during the experiments. We demonstrated the applicability of the method by measuring the effect of purinergic, TRPA1, TRPV1 and ACh receptor stimulation on intracellular Ca2+ concentration at the cellular and subcellular level. In agreement with previous results, ATP evoked reversible and repeatable Ca2+ transients in Deiters', Hensen's and Claudius' cells. TRPA1 and TRPV1 stimulation by AITC and capsaicin, respectively, failed to induce any Ca2+ response in the supporting cells, except in a single Hensen's cell in which AITC evoked transients with smaller amplitude. AITC also caused the displacement of the tissue. Carbachol, agonist of ACh receptors induced Ca2+ transients in about a third of Deiters' and fifth of Hensen's cells. Here we have presented a fast and cell-specific indicator loading method allowing subcellular functional Ca2+ imaging in supporting cells of the organ of Corti in the mature hemicochlea preparation, thus providing a straightforward tool for deciphering the poorly understood regulation of Ca2+ homeostasis in these cells.
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Affiliation(s)
- Eszter Berekméri
- Department of Pharmacology and Pharmacotherapy, Semmelweis University, Budapest, Hungary
| | - Orsolya Deák
- Department of Pharmacology and Pharmacotherapy, Semmelweis University, Budapest, Hungary
| | - Tímea Téglás
- Department of Pharmacology and Pharmacotherapy, Semmelweis University, Budapest, Hungary
| | - Éva Sághy
- Department of Pharmacology and Pharmacotherapy, Semmelweis University, Budapest, Hungary
| | - Tamás Horváth
- Department of Pharmacology and Pharmacotherapy, Semmelweis University, Budapest, Hungary
| | - Máté Aller
- Department of Pharmacology and Pharmacotherapy, Semmelweis University, Budapest, Hungary
| | - Ádám Fekete
- Program in Neurosciences and Mental Health, The Hospital for Sick Children, Toronto, ON, Canada
| | - László Köles
- Department of Pharmacology and Pharmacotherapy, Semmelweis University, Budapest, Hungary
| | - Tibor Zelles
- Department of Pharmacology and Pharmacotherapy, Semmelweis University, Budapest, Hungary.
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19
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Leisengang S, Ott D, Murgott J, Gerstberger R, Rummel C, Roth J. Primary Cultures from Rat Dorsal Root Ganglia: Responses of Neurons and Glial Cells to Somatosensory or Inflammatory Stimulation. Neuroscience 2018; 394:1-13. [PMID: 30342197 DOI: 10.1016/j.neuroscience.2018.10.018] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Revised: 09/11/2018] [Accepted: 10/09/2018] [Indexed: 12/22/2022]
Abstract
Primary cultures of rat dorsal root ganglia (DRG) consist of neurons, satellite glial cells and a moderate number of macrophages. Measurements of increased intracellular calcium [Ca2+]i induced by stimuli, have revealed that about 70% of DRG neurons are capsaicin-responsive nociceptors, while 10% responded to cooling and or menthol (putative cold sensors). Cultivation of DRG in the presence of a moderate dose of lipopolysaccharide (LPS, 1 µg/ml) enhanced capsaicin-induced Ca2+ signals. We therefore investigated further properties of DRG primary cultures stimulated with 10 µg/ml LPS for a short period. Exposure to LPS for 2 h resulted in pronounced release of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) into the supernatants of DRG cultures, increased expression of both cytokines in the DRG cells and increased TNF immunoreactivity predominantly in macrophages. We further observed an accumulation of the inflammatory transcription factors NF-IL6 and STAT3 in the nuclei of LPS-exposed DRG neurons and macrophages. In the presence of the cytotoxic agent cisplatin (5 or 10 µg/ml), the number of macrophages was decreased significantly, the growth of satellite glial cells was markedly suppressed, but the vitality and stimulus-induced Ca2+ signals of DRG neurons were not impaired. Under these conditions the LPS-induced production and expression of TNF-α and IL-6 were blunted. Our data suggest a potential role for macrophages and satellite glial cells in the initiation of inflammatory processes that develop in sensory ganglia upon injury or exposure to pathogens.
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Affiliation(s)
- Stephan Leisengang
- Department of Veterinary-Physiology and -Biochemistry, Justus-Liebig University Giessen, Frankfurter Strasse 100, D-35392 Giessen, Germany
| | - Daniela Ott
- Department of Veterinary-Physiology and -Biochemistry, Justus-Liebig University Giessen, Frankfurter Strasse 100, D-35392 Giessen, Germany
| | - Jolanta Murgott
- Department of Veterinary-Physiology and -Biochemistry, Justus-Liebig University Giessen, Frankfurter Strasse 100, D-35392 Giessen, Germany
| | - Rüdiger Gerstberger
- Department of Veterinary-Physiology and -Biochemistry, Justus-Liebig University Giessen, Frankfurter Strasse 100, D-35392 Giessen, Germany
| | - Christoph Rummel
- Department of Veterinary-Physiology and -Biochemistry, Justus-Liebig University Giessen, Frankfurter Strasse 100, D-35392 Giessen, Germany; Center for Mind, Brain and Behavior CMBB, Philipps-Universität of Marburg & Justus-Liebig-University of Giessen, Germany
| | - Joachim Roth
- Department of Veterinary-Physiology and -Biochemistry, Justus-Liebig University Giessen, Frankfurter Strasse 100, D-35392 Giessen, Germany; Center for Mind, Brain and Behavior CMBB, Philipps-Universität of Marburg & Justus-Liebig-University of Giessen, Germany.
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20
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Fodor J, Hull JJ, Köblös G, Jacquin-Joly E, Szlanka T, Fónagy A. Identification and functional characterization of the pheromone biosynthesis activating neuropeptide receptor isoforms from Mamestra brassicae. Gen Comp Endocrinol 2018; 258:60-69. [PMID: 28579335 DOI: 10.1016/j.ygcen.2017.05.024] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Revised: 05/26/2017] [Accepted: 05/31/2017] [Indexed: 11/19/2022]
Abstract
In most moth species, including Mamestra brassicae, pheromone biosynthesis activating neuropeptide (PBAN) regulates pheromone production. Generally, PBAN acts directly on the pheromone gland (PG) cells via its specific G protein-coupled receptor (i.e. PBANR) with Ca2+ as a second messenger. In this study, we identified cDNAs encoding three variants (A, B and C) of the M. brassicae PBANR (Mambr-PBANR). The full-length coding sequences were transiently expressed in cultured Trichoplusia ni cells and Sf9 cells for functional characterization. All three isoforms dose-dependently mobilized extracellular Ca2+ in response to PBAN analogs with Mambr-PBANR-C exhibiting the greatest sensitivity. Fluorescent confocal microscopy imaging studies demonstrated binding of a rhodamine red-labeled ligand (RR10CPBAN) to all three Mambr-PBANR isoforms. RR10CPBAN binding did not trigger ligand-induced internalization in cells expressing PBANR-A, but did in cells expressing the PBANR-B and -C isoforms. Furthermore, activation of the PBANR-B and -C isoforms with the 18 amino acid Mambr-pheromonotropin resulted in co-localization with a Drosophila melanogaster arrestin homolog (Kurtz), whereas stimulation with an unrelated peptide had no effect. PCR-based profiling of the three transcripts revealed a basal level of expression throughout development with a dramatic increase in PG transcripts from the day of adult emergence with PBANR-C being the most abundant.
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Affiliation(s)
- József Fodor
- Plant Protection Institute, Centre for Agricultural Research, Hungarian Academy of Sciences, H-1022 Budapest, Hungary
| | - J Joe Hull
- Agricultural Research Service, United States Department of Agriculture, Arid Land Agricultural Research Center, Maricopa, AZ, USA
| | - Gabriella Köblös
- Plant Protection Institute, Centre for Agricultural Research, Hungarian Academy of Sciences, H-1022 Budapest, Hungary.
| | - Emmanuelle Jacquin-Joly
- INRA iEES-Paris, Institute of Ecology and Environmental Sciences, Route de Saint-Cyr, Cedex 78026 Versailles, France
| | - Tamás Szlanka
- Institute of Biochemistry, Biological Research Centre, Hungarian Academy of Sciences, H-6726 Szeged, Hungary
| | - Adrien Fónagy
- Plant Protection Institute, Centre for Agricultural Research, Hungarian Academy of Sciences, H-1022 Budapest, Hungary
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21
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Ellefsen KL, Parker I. Dynamic Ca 2+ imaging with a simplified lattice light-sheet microscope: A sideways view of subcellular Ca 2+ puffs. Cell Calcium 2018; 71:34-44. [PMID: 29604962 DOI: 10.1016/j.ceca.2017.11.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Revised: 11/29/2017] [Accepted: 11/30/2017] [Indexed: 11/24/2022]
Abstract
We describe the construction of a simplified, inexpensive lattice light-sheet microscope, and illustrate its use for imaging subcellular Ca2+ puffs evoked by photoreleased i-IP3 in cultured SH-SY5Y neuroblastoma cells loaded with the Ca2+ probe Cal520. The microscope provides sub-micron spatial resolution and enables recording of local Ca2+ transients in single-slice mode with a signal-to-noise ratio and temporal resolution (2ms) at least as good as confocal or total internal reflection microscopy. Signals arising from openings of individual IP3R channels are clearly resolved, as are stepwise changes in fluorescence reflecting openings and closings of individual channels during puffs. Moreover, by stepping the specimen through the light-sheet, the entire volume of a cell can be scanned within a few hundred ms. The ability to directly visualize a sideways (axial) section through cells directly reveals that IP3-evoked Ca2+ puffs originate at sites in very close (≤a few hundred nm) to the plasma membrane, suggesting they play a specific role in signaling to the membrane.
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22
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Li Y, Mathis A, Grewe BF, Osterhout JA, Ahanonu B, Schnitzer MJ, Murthy VN, Dulac C. Neuronal Representation of Social Information in the Medial Amygdala of Awake Behaving Mice. Cell 2017; 171:1176-1190.e17. [PMID: 29107332 PMCID: PMC5731476 DOI: 10.1016/j.cell.2017.10.015] [Citation(s) in RCA: 140] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Revised: 07/27/2017] [Accepted: 10/11/2017] [Indexed: 12/16/2022]
Abstract
The medial amygdala (MeA) plays a critical role in processing species- and sex-specific signals that trigger social and defensive behaviors. However, the principles by which this deep brain structure encodes social information is poorly understood. We used a miniature microscope to image the Ca2+ dynamics of large neural ensembles in awake behaving mice and tracked the responses of MeA neurons over several months. These recordings revealed spatially intermingled subsets of MeA neurons with distinct temporal dynamics. The encoding of social information in the MeA differed between males and females and relied on information from both individual cells and neuronal populations. By performing long-term Ca2+ imaging across different social contexts, we found that sexual experience triggers lasting and sex-specific changes in MeA activity, which, in males, involve signaling by oxytocin. These findings reveal basic principles underlying the brain's representation of social information and its modulation by intrinsic and extrinsic factors.
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Affiliation(s)
- Ying Li
- Howard Hughes Medical Institute, Harvard University, Cambridge, MA, USA; Department of Molecular and Cellular Biology and Center for Brain Science, Harvard University, Cambridge, MA, USA
| | - Alexander Mathis
- Department of Molecular and Cellular Biology and Center for Brain Science, Harvard University, Cambridge, MA, USA
| | - Benjamin F Grewe
- Howard Hughes Medical Institute, CNC Program, James H. Clark Center Biomedical Engineering & Sciences, Stanford University, Stanford, CA, USA
| | - Jessica A Osterhout
- Howard Hughes Medical Institute, Harvard University, Cambridge, MA, USA; Department of Molecular and Cellular Biology and Center for Brain Science, Harvard University, Cambridge, MA, USA
| | - Biafra Ahanonu
- Howard Hughes Medical Institute, CNC Program, James H. Clark Center Biomedical Engineering & Sciences, Stanford University, Stanford, CA, USA
| | - Mark J Schnitzer
- Howard Hughes Medical Institute, CNC Program, James H. Clark Center Biomedical Engineering & Sciences, Stanford University, Stanford, CA, USA
| | - Venkatesh N Murthy
- Department of Molecular and Cellular Biology and Center for Brain Science, Harvard University, Cambridge, MA, USA
| | - Catherine Dulac
- Howard Hughes Medical Institute, Harvard University, Cambridge, MA, USA; Department of Molecular and Cellular Biology and Center for Brain Science, Harvard University, Cambridge, MA, USA.
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23
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Gengyo-Ando K, Kagawa-Nagamura Y, Ohkura M, Fei X, Chen M, Hashimoto K, Nakai J. A new platform for long-term tracking and recording of neural activity and simultaneous optogenetic control in freely behaving Caenorhabditis elegans. J Neurosci Methods 2017; 286:56-68. [PMID: 28506879 DOI: 10.1016/j.jneumeth.2017.05.017] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Revised: 05/10/2017] [Accepted: 05/11/2017] [Indexed: 10/19/2022]
Abstract
BACKGROUND Real-time recording and manipulation of neural activity in freely behaving animals can greatly advance our understanding of how neural circuits regulate behavior. Ca2+ imaging and optogenetic manipulation with optical probes are key technologies for this purpose. However, integrating the two optical approaches with behavioral analysis has been technically challenging. NEW METHOD Here, we developed a new imaging system, ICaST (Integrated platform for Ca2+ imaging, Stimulation, and Tracking), which combines an automatic worm tracking system and a fast-scanning laser confocal microscope, to image neurons of interest in freely behaving C. elegans. We optimized different excitation wavelengths for the concurrent use of channelrhodopsin-2 and G-CaMP, a green fluorescent protein (GFP)-based, genetically encoded Ca2+ indicator. RESULTS Using ICaST in conjunction with an improved G-CaMP7, we successfully achieved long-term tracking and Ca2+ imaging of the AVA backward command interneurons while tracking the head of a moving animal. We also performed all-optical manipulation and simultaneous recording of Ca2+ dynamics from GABAergic motor neurons in conjunction with behavior monitoring. COMPARISON WITH EXISTING METHOD(S) Our system differs from conventional systems in that it does not require fluorescent markers for tracking and can track any part of the worm's body via bright-field imaging at high magnification. Consequently, this approach enables the long-term imaging of activity from neurons or nerve processes of interest with high spatiotemporal resolution. CONCLUSION Our imaging system is a powerful tool for studying the neural circuit mechanisms of C. elegans behavior and has potential for use in other small animals.
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24
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de Juan-Sanz J, Holt GT, Schreiter ER, de Juan F, Kim DS, Ryan TA. Axonal Endoplasmic Reticulum Ca 2+ Content Controls Release Probability in CNS Nerve Terminals. Neuron 2017; 93:867-881.e6. [PMID: 28162809 DOI: 10.1016/j.neuron.2017.01.010] [Citation(s) in RCA: 170] [Impact Index Per Article: 24.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2016] [Revised: 11/23/2016] [Accepted: 01/13/2017] [Indexed: 12/14/2022]
Abstract
Although the endoplasmic reticulum (ER) extends throughout axons and axonal ER dysfunction is implicated in numerous neurological diseases, its role at nerve terminals is poorly understood. We developed novel genetically encoded ER-targeted low-affinity Ca2+ indicators optimized for examining axonal ER Ca2+. Our experiments revealed that presynaptic function is tightly controlled by ER Ca2+ content. We found that neuronal activity drives net Ca2+ uptake into presynaptic ER although this activity does not contribute significantly to shaping cytosolic Ca2+ except during prolonged repetitive firing. In contrast, we found that axonal ER acts as an actuator of plasma membrane (PM) function: [Ca2+]ER controls STIM1 activation in presynaptic terminals, which results in the local modulation of presynaptic function, impacting activity-driven Ca2+ entry and release probability. These experiments reveal a critical role of presynaptic ER in the control of neurotransmitter release and will help frame future investigations into the molecular basis of ER-driven neuronal disease states.
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Affiliation(s)
- Jaime de Juan-Sanz
- Department of Biochemistry, Weill Cornell Medicine, New York, NY 10065, USA
| | - Graham T Holt
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Eric R Schreiter
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Fernando de Juan
- Department of Physics, University of Oxford, Oxford, OX1 3NP, UK
| | - Douglas S Kim
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Timothy A Ryan
- Department of Biochemistry, Weill Cornell Medicine, New York, NY 10065, USA.
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25
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Turovsky EA, Turovskaya MV, Gaidin SG, Zinchenko VP. Cytokine IL-10, activators of PI3-kinase, agonists of α-2 adrenoreceptor and antioxidants prevent ischemia-induced cell death in rat hippocampal cultures. Arch Biochem Biophys 2017; 615:35-43. [PMID: 28063948 DOI: 10.1016/j.abb.2017.01.001] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Revised: 12/21/2016] [Accepted: 01/03/2017] [Indexed: 12/27/2022]
Abstract
In the present work we compared the protective effect of anti-inflammatory cytokine IL-10 with the action of a PI3-kinase selective activator 740 Y-P, selective agonists of alpha-2 adrenoreceptor, guanfacine and UK-14,304, and compounds having antioxidant effect: recombinant human peroxiredoxin 6 and B27, in hippocampal cell culture during OGD (ischemia-like conditions). It has been shown that the response of cells to OGD in the control includes two phases. The first phase was accompanied by an increase in the frequency of spontaneous synchronous Ca2+-oscillations (SSCO) in neurons and Ca2+-pulse in astrocytes. Spontaneous Ca2+ events in astrocytes during ischemia in control experiments disappeared. The second phase started after a few minutes of OGD and looked like a sharp/avalanche, global synchronic (within 20 s) increase in [Ca2+]i in many cells. Within 1 h after OGD, a mass death of cells, primarily astrocytes, was observed. To study the protective action of the compounds, cells were incubated in the presence of the neuroprotective agents for 10-40 min or 24 h before ischemia. All the neuroprotective agents delayed a global [Ca2+]i increase during OGD or completely inhibited this process and increased cell survival.
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26
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Caseley EA, Muench SP, Fishwick CW, Jiang LH. Structure-based identification and characterisation of structurally novel human P2X7 receptor antagonists. Biochem Pharmacol 2016; 116:130-9. [PMID: 27481062 PMCID: PMC5012888 DOI: 10.1016/j.bcp.2016.07.020] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Accepted: 07/28/2016] [Indexed: 12/13/2022]
Abstract
The P2X7 receptor (P2X7R) plays an important role in diverse conditions associated with tissue damage and inflammation, meaning that the human P2X7R (hP2X7R) is an attractive therapeutic target. The crystal structures of the zebrafish P2X4R in the closed and ATP-bound open states provide an unprecedented opportunity for structure-guided identification of new ligands. The present study performed virtual screening of ∼100,000 structurally diverse compounds against the ATP-binding pocket in the hP2X7R. This identified three compounds (C23, C40 and C60) out of 73 top-ranked compounds by testing against hP2X7R-mediated Ca(2+) responses. These compounds were further characterised using Ca(2+) imaging, patch-clamp current recording, YO-PRO-1 uptake and propidium iodide cell death assays. All three compounds inhibited BzATP-induced Ca(2+) responses concentration-dependently with IC50s of 5.1±0.3μM, 4.8±0.8μM and 3.2±0.2μM, respectively. C23 and C40 inhibited BzATP-induced currents in a reversible and concentration-dependent manner, with IC50s of 0.35±0.3μM and 1.2±0.1μM, respectively, but surprisingly C60 did not affect BzATP-induced currents up to 100μM. They suppressed BzATP-induced YO-PRO-1 uptake with IC50s of 1.8±0.9μM, 1.0±0.1μM and 0.8±0.2μM, respectively. Furthermore, these three compounds strongly protected against ATP-induced cell death. Among them, C40 and C60 exhibited strong specificity towards the hP2X7R over the hP2X4R and rP2X3R. In conclusion, our study reports the identification of three novel hP2X7R antagonists with micromolar potency for the first time using a structure-based approach, including the first P2X7R antagonist with preferential inhibition of large pore formation.
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MESH Headings
- Adenosine Triphosphate/analogs & derivatives
- Adenosine Triphosphate/chemistry
- Adenosine Triphosphate/metabolism
- Adenosine Triphosphate/pharmacology
- Amides/chemistry
- Amides/metabolism
- Amides/pharmacology
- Animals
- Anti-Inflammatory Agents, Non-Steroidal/chemistry
- Anti-Inflammatory Agents, Non-Steroidal/metabolism
- Anti-Inflammatory Agents, Non-Steroidal/pharmacology
- Binding Sites
- Calcium Signaling/drug effects
- HEK293 Cells
- Hepatocytes/cytology
- Hepatocytes/drug effects
- Hepatocytes/metabolism
- Humans
- Image Processing, Computer-Assisted
- Indoles/chemistry
- Indoles/metabolism
- Indoles/pharmacology
- Ligands
- Microscopy, Fluorescence
- Models, Molecular
- Patch-Clamp Techniques
- Purinergic P2X Receptor Antagonists/chemistry
- Purinergic P2X Receptor Antagonists/metabolism
- Purinergic P2X Receptor Antagonists/pharmacology
- Rats
- Receptors, Purinergic P2X3/chemistry
- Receptors, Purinergic P2X3/genetics
- Receptors, Purinergic P2X3/metabolism
- Receptors, Purinergic P2X4/chemistry
- Receptors, Purinergic P2X4/genetics
- Receptors, Purinergic P2X4/metabolism
- Receptors, Purinergic P2X7/chemistry
- Receptors, Purinergic P2X7/genetics
- Receptors, Purinergic P2X7/metabolism
- Recombinant Proteins/chemistry
- Recombinant Proteins/metabolism
- Single-Cell Analysis
- Small Molecule Libraries
- Structure-Activity Relationship
- Thiophenes/chemistry
- Thiophenes/metabolism
- Thiophenes/pharmacology
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Affiliation(s)
- Emily A Caseley
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, UK
| | - Stephen P Muench
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, UK
| | | | - Lin-Hua Jiang
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, UK.
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27
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Kikuta S, Endo H, Tomita N, Takada T, Morita C, Asaoka K, Sato R. Characterization of a ligand-gated cation channel based on an inositol receptor in the silkworm, Bombyx mori. Insect Biochemistry and Molecular Biology 2016; 74:12-20. [PMID: 27132146 DOI: 10.1016/j.ibmb.2016.04.010] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2015] [Revised: 04/25/2016] [Accepted: 04/26/2016] [Indexed: 06/05/2023]
Abstract
Insect herbivores recognize non-volatile compounds in plants to direct their feeding behavior. Gustatory receptors (Gr) appear to be required for nutrient recognition by gustatory organs in the mouthparts of insects. Gr10 is expressed in Bombyx mori (BmGr10) mouthparts such as maxillary galea, maxillary palp, and labrum. BmGr10 is predicted to function in sugar recognition; however, the precise biochemical function remains obscure. Larvae of B. mori are monophagous feeders able to find and feed on mulberry leaves. Soluble mulberry leaf extract contains sucrose, glucose, fructose, and myo-inositol. In this study, we identified BmGr10 as an inositol receptor using electrophysiological analysis with the Xenopus oocyte expression system and Ca(2+) imaging techniques using mammalian cells. These results demonstrated that Xenopus oocytes or HEK293T cells expressing BmGr10 specifically respond to myo-inositol and epi-inositol but do not respond to any mono-, di-, or tri-saccharides or to some sugar alcohols. These inositols caused Ca(2+) and Na(+) influxes into the cytoplasm independently of a G protein-mediated signaling cascade, indicating that BmGr10 is a ligand-gated cation channel. Overall, BmGr10 plays an important role in the myo-inositol recognition required for B. mori larval feeding behavior.
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Affiliation(s)
- Shingo Kikuta
- Graduate School of Bio-Applications and Systems Engineering, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan
| | - Haruka Endo
- Graduate School of Bio-Applications and Systems Engineering, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan
| | - Natsuo Tomita
- Graduate School of Bio-Applications and Systems Engineering, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan
| | - Tomoyuki Takada
- Graduate School of Bio-Applications and Systems Engineering, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan
| | - Chiharu Morita
- Graduate School of Bio-Applications and Systems Engineering, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan
| | - Kiyoshi Asaoka
- National Institute of Agrobiological Sciences, Tsukuba, Ibaraki 305-8602, Japan
| | - Ryoichi Sato
- Graduate School of Bio-Applications and Systems Engineering, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan.
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28
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Tsukamoto Y, Nagata S. Newly identified allatostatin Bs and their receptor in the two-spotted cricket, Gryllus bimaculatus. Peptides 2016; 80:25-31. [PMID: 27018343 DOI: 10.1016/j.peptides.2016.03.015] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Revised: 03/22/2016] [Accepted: 03/23/2016] [Indexed: 01/11/2023]
Abstract
A cDNA encoding allatostatin Bs (ASTBs) containing the W(X)6W motif was identified using a database generated by a next generation sequencer (NGS) in the two-spotted cricket, Gryllus bimaculatus. The contig sequence revealed the presence of five novel putative ASTBs (GbASTBs) in addition to GbASTBs previously identified in G. bimaculatus. MALDI-TOF MS analyses revealed the presence of these novel and previously identified GbASTBs with three missing GbASTBs. We also identified a cDNA encoding G. bimaculatus GbASTB receptor (GbASTBR) in the NGS data. Phylogenetic analysis demonstrated that this receptor was highly conserved with other insect ASTBRs, including the sex peptide receptor of Drosophila melanogaster. Calcium imaging analyses indicated that the GbASTBR heterologously expressed in HEK293 cells exhibited responses to all identified GbASTBs at a concentration range of 10(-10)-10(-5)M.
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Affiliation(s)
- Yusuke Tsukamoto
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Chiba 277-8567, Japan; Research Fellow of Japan Society for the Promotion of Science (JSPS), Japan
| | - Shinji Nagata
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Chiba 277-8567, Japan.
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29
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Kortus S, Srinivasan C, Forostyak O, Zapotocky M, Ueta Y, Sykova E, Chvatal A, Verkhratsky A, Dayanithi G. Sodium-calcium exchanger and R-type Ca(2+) channels mediate spontaneous [Ca(2+)]i oscillations in magnocellular neurones of the rat supraoptic nucleus. Cell Calcium 2016; 59:289-98. [PMID: 27052156 DOI: 10.1016/j.ceca.2016.03.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Revised: 03/30/2016] [Accepted: 03/30/2016] [Indexed: 10/22/2022]
Abstract
Isolated supraoptic neurones generate spontaneous [Ca(2+)]i oscillations in isolated conditions. Here we report in depth analysis of the contribution of plasmalemmal ion channels (Ca(2+), Na(+)), Na(+)/Ca(2+) exchanger (NCX), intracellular Ca(2+) release channels (InsP3Rs and RyRs), Ca(2+) storage organelles, plasma membrane Ca(2+) pump and intracellular signal transduction cascades into spontaneous Ca(2+) activity. While removal of extracellular Ca(2+) or incubation with non-specific voltage-gated Ca(2+) channel (VGCC) blocker Cd(2+) suppressed the oscillations, neither Ni(2+) nor TTA-P2, the T-type VGCC blockers, had an effect. Inhibitors of VGCC nicardipine, ω-conotoxin GVIA, ω-conotoxin MVIIC, ω-agatoxin IVA (for L-, N-, P and P/Q-type channels, respectively) did not affect [Ca(2+)]i oscillations. In contrast, a specific R-type VGCC blocker SNX-482 attenuated [Ca(2+)]i oscillations. Incubation with TTX had no effect, whereas removal of the extracellular Na(+) or application of an inhibitor of the reverse operation mode of Na(+)/Ca(2+) exchanger KB-R7943 blocked the oscillations. The mitochondrial uncoupler CCCP irreversibly blocked spontaneous [Ca(2+)]i activity. Exposure of neurones to Ca(2+) mobilisers (thapsigargin, cyclopiazonic acid, caffeine and ryanodine); 4-aminopyridine (A-type K(+) current blocker); phospholipase C and adenylyl cyclase pathways blockers U-73122, Rp-cAMP, SQ-22536 and H-89 had no effect. Oscillations were blocked by GABA, but not by glutamate, apamin or dynorphin. In conclusion, spontaneous oscillations in magnocellular neurones are mediated by a concerted action of R-type Ca(2+) channels and the NCX fluctuating between forward and reverse modes.
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Affiliation(s)
- Stepan Kortus
- Department of Molecular Neurophysiology, Institute of Experimental Medicine, Czech Academy of Sciences, Videnska 1083, 14220 Prague, Czech Republic; Institute of Physiology, Czech Academy of Sciences, Videnska 1083, 14220 Prague, Czech Republic; Institute of Biophysics and Informatics, First Medical Faculty, Charles University in Prague, Salmovska 1, 12000 Prague, Czech Republic
| | - Chinnapaiyan Srinivasan
- Department of Molecular Neurophysiology, Institute of Experimental Medicine, Czech Academy of Sciences, Videnska 1083, 14220 Prague, Czech Republic
| | - Oksana Forostyak
- Department of Molecular Neurophysiology, Institute of Experimental Medicine, Czech Academy of Sciences, Videnska 1083, 14220 Prague, Czech Republic; Department of Neuroscience, Charles University, Second Medical Faculty, V Uvalu 84, 15006 Prague, Czech Republic
| | - Martin Zapotocky
- Institute of Physiology, Czech Academy of Sciences, Videnska 1083, 14220 Prague, Czech Republic; Institute of Biophysics and Informatics, First Medical Faculty, Charles University in Prague, Salmovska 1, 12000 Prague, Czech Republic
| | - Yoichi Ueta
- Department of Physiology, School of Medicine, University of Occupational and Environmental Health, Kitakyushu 807-8555, Japan
| | - Eva Sykova
- Department of Neuroscience, Charles University, Second Medical Faculty, V Uvalu 84, 15006 Prague, Czech Republic; Department of Neuroscience, Institute of Experimental Medicine, Czech Academy of Sciences, Videnska 1083, 14220 Prague, Czech Republic
| | - Alexandr Chvatal
- Department of Neuroscience, Charles University, Second Medical Faculty, V Uvalu 84, 15006 Prague, Czech Republic; Department of Cellular Neurophysiology, Institute of Experimental Medicine, Czech Academy of Sciences, Videnska 1083, 14220 Prague, Czech Republic
| | - Alexei Verkhratsky
- University of Manchester, School of Biological Sciences, D.4417 Michael Smith Building, Oxford Road, M13 9PT Manchester, United Kingdom; Achucarro Center for Neuroscience, IKERBASQUE, Basque Foundation for Science, 48011 Bilbao, Spain; Department of Neurosciences, University of the Basque Country UPV/EHU and CIBERNED, Leioa, Spain; University of Nizhny Novgorod, Nizhny Novgorod 603022, Russia.
| | - Govindan Dayanithi
- Department of Molecular Neurophysiology, Institute of Experimental Medicine, Czech Academy of Sciences, Videnska 1083, 14220 Prague, Czech Republic; Institut National de la Santé et de la Recherche Médicale, Unité de recherche U1198, Université Montpellier, 34095 Montpellier, France; Ecole Practique des Hautes Etudes, Sorbonne, 75014 Paris, France.
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Gourévitch B, Cai J, Mellen N. Cellular and network-level adaptations to in utero methadone exposure along the ventral respiratory column in the neonate rat. Exp Neurol 2016; 287:S0014-4886(16)30063-2. [PMID: 27009496 DOI: 10.1016/j.expneurol.2016.03.020] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Revised: 03/17/2016] [Accepted: 03/18/2016] [Indexed: 11/15/2022]
Abstract
Neonatal abstinence syndrome (NAS) occurs in babies chronically exposed to opioids during pregnancy. NAS shares features with opioid withdrawal symptoms seen in adults, including autonomic dysregulation. Here, the effect of low-dose in utero methadone (MTD) exposure on respiration-modulated networks along the ventral respiratory column (VRC) in ventrolateral medulla was investigated in the neonate Sprague-Dawley rat. MTD was administered via drinking water (3mg/kg/day in drinking water of the mother E7-E21). Lower expression levels of myelin-associated proteins phosphorylated axonal neurofilament subunit H (pNFH), 2',3'-Cyclicnucleotide 3'-phosphodiesterase (CNPase) and myelin basic protein (MBP), in MTD-exposed pups compared to controls at P3, P6 and P10 indicated MTD transport across the placenta. We investigated whether in utero MTD exposure led to network-level excitability changes consistent with tolerance, and also probed for changes in endogenous opioid modulation of respiratory networks. To this end, high-speed (45.5Hz) optical recordings of respiratory network activity in control and MTD-exposed neonate (P0-P2) pups before and during administration of the μ-opioid receptor antagonist naloxone (NAL; 10μM) were carried out. Spike rate was estimated from optical traces via deconvolution, and coupling between all neuron pairs in recorded networks was quantified using the normalized transfer entropy (NTE). Recordings of local networks along the VRC, together with recordings of respiratory output from ventral root C1 did not reveal changes in respiratory activity at the system level, but cellular and network changes in MTD-exposed pups were consistent with the development of opioid tolerance. MTD-exposed pups were found to have i. higher neuronal firing rates; ii. higher covariance between neuronal activity and motor output; iii. more bidirectionally and unidirectionally coupled neurons, and fewer uncoupled neurons; iv. stronger coupling and shorter integration times between network constituents. The μ-opioid receptor antagonist NAL did not alter system-level function. The correlation between the activity of neurons caudal to -400μm and motor output was significantly reduced in control animals following NAL. In both control and MTD-exposed pups, the relative number of neurons whose correlation with motor output increased following NAL followed a rostrocaudal gradient along the VRC, with fewer neurons caudally, and more neurons rostrally. The up-regulation of coupling strength, firing rate and coefficient of variation between neurons and motor output following in utero opioid exposure suggests that these networks may contribute to NAS in infants born to opioid-dependent mothers.
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Affiliation(s)
- Boris Gourévitch
- NeuroPSI, UMR CNRS 8195, Bâtiment 446, 91405 Orsay cedex, France; Université Paris-Sud, Bâtiment 446, 91405 Orsay cedex, France
| | - Jun Cai
- Kosair Children's Hospital Research Institute, University of Louisville, Louisville, KY 40206, USA
| | - Nicholas Mellen
- Kosair Children's Hospital Research Institute, University of Louisville, Louisville, KY 40206, USA.
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31
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Tanamoto R, Shindo Y, Niwano M, Matsumoto Y, Miki N, Hotta K, Oka K. Qualitative and quantitative estimation of comprehensive synaptic connectivity in short- and long-term cultured rat hippocampal neurons with new analytical methods inspired by Scatchard and Hill plots. Biochem Biophys Res Commun 2016; 471:486-91. [PMID: 26896767 DOI: 10.1016/j.bbrc.2016.02.048] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Accepted: 02/14/2016] [Indexed: 02/04/2023]
Abstract
To investigate comprehensive synaptic connectivity, we examined Ca(2+) responses with quantitative electric current stimulation by indium-tin-oxide (ITO) glass electrode with transparent and high electro-conductivity. The number of neurons with Ca(2+) responses was low during the application of stepwise increase of electric current in short-term cultured neurons (less than 17 days in-vitro (DIV)). The neurons cultured over 17 DIV showed two-type responses: S-shaped (sigmoid) and monotonous saturated responses, and Scatchard plots well illustrated the difference of these two responses. Furthermore, sigmoid like neural network responses over 17 DIV were altered to the monotonous saturated ones by the application of the mixture of AP5 and CNQX, specific blockers of NMDA and AMPA receptors, respectively. This alternation was also characterized by the change of Hill coefficients. These findings indicate that the neural network with sigmoid-like responses has strong synergetic or cooperative synaptic connectivity via excitatory glutamate synapses.
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Affiliation(s)
- Ryo Tanamoto
- Department of Biosciences and Informatics, Faculty of Science and Technology, Keio University, Japan
| | - Yutaka Shindo
- Department of Biosciences and Informatics, Faculty of Science and Technology, Keio University, Japan
| | - Mariko Niwano
- Department of Biosciences and Informatics, Faculty of Science and Technology, Keio University, Japan
| | - Yoshinori Matsumoto
- Department of Applied Physics and Physico-Informatics, Faculty of Science and Technology, Keio University, Japan
| | - Norihisa Miki
- Department of Mechanical Engineering, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama, Kanagawa, 223-8522, Japan
| | - Kohji Hotta
- Department of Biosciences and Informatics, Faculty of Science and Technology, Keio University, Japan
| | - Kotaro Oka
- Department of Biosciences and Informatics, Faculty of Science and Technology, Keio University, Japan.
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Ibrahim LA, Mesik L, Ji XY, Fang Q, Li HF, Li YT, Zingg B, Zhang LI, Tao HW. Cross-Modality Sharpening of Visual Cortical Processing through Layer-1-Mediated Inhibition and Disinhibition. Neuron 2016; 89:1031-45. [PMID: 26898778 DOI: 10.1016/j.neuron.2016.01.027] [Citation(s) in RCA: 178] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Revised: 12/08/2015] [Accepted: 01/12/2016] [Indexed: 11/18/2022]
Abstract
Cross-modality interaction in sensory perception is advantageous for animals' survival. How cortical sensory processing is cross-modally modulated and what are the underlying neural circuits remain poorly understood. In mouse primary visual cortex (V1), we discovered that orientation selectivity of layer (L)2/3, but not L4, excitatory neurons was sharpened in the presence of sound or optogenetic activation of projections from primary auditory cortex (A1) to V1. The effect was manifested by decreased average visual responses yet increased responses at the preferred orientation. It was more pronounced at lower visual contrast and was diminished by suppressing L1 activity. L1 neurons were strongly innervated by A1-V1 axons and excited by sound, while visual responses of L2/L3 vasoactive intestinal peptide (VIP) neurons were suppressed by sound, both preferentially at the cell's preferred orientation. These results suggest that the cross-modality modulation is achieved primarily through L1 neuron- and L2/L3 VIP-cell-mediated inhibitory and disinhibitory circuits.
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Affiliation(s)
- Leena A Ibrahim
- Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA; Neuroscience Graduate Program, University of Southern California, Los Angeles, CA 90033, USA
| | - Lukas Mesik
- Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA; Neuroscience Graduate Program, University of Southern California, Los Angeles, CA 90033, USA
| | - Xu-Ying Ji
- Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Qi Fang
- Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA; Neuroscience Graduate Program, University of Southern California, Los Angeles, CA 90033, USA
| | - Hai-Fu Li
- Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Ya-Tang Li
- Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Brian Zingg
- Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA; Neuroscience Graduate Program, University of Southern California, Los Angeles, CA 90033, USA
| | - Li I Zhang
- Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA; Department of Physiology and Biophysics, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA.
| | - Huizhong Whit Tao
- Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA; Department of Cell and Neurobiology, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA.
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Miyamoto D, Murayama M. The fiber-optic imaging and manipulation of neural activity during animal behavior. Neurosci Res 2015; 103:1-9. [PMID: 26427958 DOI: 10.1016/j.neures.2015.09.004] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2015] [Revised: 08/31/2015] [Accepted: 09/01/2015] [Indexed: 12/12/2022]
Abstract
Recent progress with optogenetic probes for imaging and manipulating neural activity has further increased the relevance of fiber-optic systems for neural circuitry research. Optical fibers, which bi-directionally transmit light between separate sites (even at a distance of several meters), can be used for either optical imaging or manipulating neural activity relevant to behavioral circuitry mechanisms. The method's flexibility and the specifications of the light structure are well suited for following the behavior of freely moving animals. Furthermore, thin optical fibers allow researchers to monitor neural activity from not only the cortical surface but also deep brain regions, including the hippocampus and amygdala. Such regions are difficult to target with two-photon microscopes. Optogenetic manipulation of neural activity with an optical fiber has the advantage of being selective for both cell-types and projections as compared to conventional electrophysiological brain tissue stimulation. It is difficult to extract any data regarding changes in neural activity solely from a fiber-optic manipulation device; however, the readout of data is made possible by combining manipulation with electrophysiological recording, or the simultaneous application of optical imaging and manipulation using a bundle-fiber. The present review introduces recent progress in fiber-optic imaging and manipulation methods, while also discussing fiber-optic system designs that are suitable for a given experimental protocol.
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Affiliation(s)
- Daisuke Miyamoto
- Behavioral Neurophysiology Laboratory, Brain Science Institute, Riken, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Masanori Murayama
- Behavioral Neurophysiology Laboratory, Brain Science Institute, Riken, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
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Lukewich MK, Lomax AE. Mouse models of sepsis elicit spontaneous action potential discharge and enhance intracellular Ca2+ signaling in postganglionic sympathetic neurons. Neuroscience 2015; 284:668-677. [PMID: 25450963 DOI: 10.1016/j.neuroscience.2014.10.039] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2014] [Revised: 10/10/2014] [Accepted: 10/22/2014] [Indexed: 11/30/2022]
Abstract
Sepsis is a severe systemic inflammatory disorder that rapidly activates the sympathetic nervous system to enhance catecholamine secretion from postganglionic sympathetic neurons and adrenal chromaffin cells. Although an increase in preganglionic drive to postganglionic sympathetic tissues has been known to contribute to this response for quite some time, only recently was it determined that sepsis also has direct effects on adrenal chromaffin cell Ca2+ signaling and epinephrine release. In the present study, we characterized the direct effects of sepsis on postganglionic sympathetic neuron function. Using the endotoxemia model of sepsis in mice, we found that almost a quarter of postganglionic neurons acquired the ability to fire spontaneous action potentials, which was absent in cells from control mice. Spontaneously firing neurons possessed significantly lower rheobases and fired a greater number of action potentials at twice the rheobase compared to neurons from control mice. Sepsis did not significantly affect voltage-gated Ca2+ currents. However, global Ca2+ signaling was enhanced in postganglionic neurons isolated from 1 to 24 h endotoxemic mice. A similar increase in the amplitude of high-K+-stimulated Ca2+ transients was observed during the cecal ligation and puncture model of sepsis. The enhanced excitability and Ca2+ signaling produced during sepsis likely amplify the effect of increased preganglionic drive on norepinephrine release from postganglionic neurons. This is important, as sympathetic neurons are integral to the anti-inflammatory autonomic reflex that is activated during sepsis.
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Affiliation(s)
- M K Lukewich
- Department of Biomedical and Molecular Sciences, Gastrointestinal Diseases Research Unit and Centre for Neuroscience Studies, Queen's University, Kingston, Ontario, Canada; Department of Biological Sciences, Brock University, St. Catharines, Ontario, Canada
| | - A E Lomax
- Department of Biomedical and Molecular Sciences, Gastrointestinal Diseases Research Unit and Centre for Neuroscience Studies, Queen's University, Kingston, Ontario, Canada; Department of Medicine, Gastrointestinal Diseases Research Unit and Centre for Neuroscience Studies, Queen's University, Kingston, Ontario, Canada.
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35
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McMahon SM, Jackson MB. In situ Ca2+ titration in the fluorometric study of intracellular Ca2+ binding. Cell Calcium 2014; 56:504-12. [PMID: 25465896 DOI: 10.1016/j.ceca.2014.10.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2014] [Revised: 10/15/2014] [Accepted: 10/20/2014] [Indexed: 12/15/2022]
Abstract
Imaging with Ca(2+)-sensitive fluorescent dye has provided a wealth of insight into the dynamics of cellular Ca(2+) signaling. The spatiotemporal evolution of intracellular free Ca(2+) observed in imaging experiments is shaped by binding and unbinding to cytoplasmic Ca(2+) buffers, as well as the fluorescent indicator used for imaging. These factors must be taken into account in the interpretation of Ca(2+) imaging data, and can be exploited to investigate endogenous Ca(2+) buffer properties. Here we extended the use of Ca(2+) fluorometry in the characterization of Ca(2+) binding molecules within cells, building on a method of titration of intracellular Ca(2+) binding sites in situ with measured amounts of Ca(2+) entering through voltage-gated Ca(2+) channels. We developed a systematic procedure for fitting fluorescence data acquired during a series of voltage steps to models with multiple Ca(2+) binding sites. The method was tested on simulated data, and then applied to 2-photon fluorescence imaging data from rat posterior pituitary nerve terminals patch clamp-loaded with the Ca(2+) indicator fluo-8. Focusing on data sets well described by a single endogenous Ca(2+) buffer and dye, this method yielded estimates of the endogenous buffer concentration and Kd, the dye Kd, and the fraction of Ca(2+) inaccessible cellular volume. The in situ Kd of fluo-8 thus obtained was indistinguishable from that measured in vitro. This method of calibrating Ca(2+)-sensitive fluorescent dyes in situ has significant advantages over previous methods. Our analysis of Ca(2+) titration fluorometric data makes more effective use of the experimental data, and provides a rigorous treatment of multivariate errors and multiple Ca(2+) binding species. This method offers a versatile approach to the study of endogenous Ca(2+) binding molecules in their physiological milieu.
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Yamakawa H, Murata M, Suzuki T, Yada H, Ishida H, Aizawa Y, Adachi T, Kamiya K, Fukuda K. Suppression of Rad leads to arrhythmogenesis via PKA-mediated phosphorylation of ryanodine receptor activity in the heart. Biochem Biophys Res Commun 2014; 452:701-7. [PMID: 25193703 DOI: 10.1016/j.bbrc.2014.08.126] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2014] [Accepted: 08/25/2014] [Indexed: 11/22/2022]
Abstract
Ras-related small G-protein Rad plays a critical role in generating arrhythmias via regulation of the L-type Ca(2+) channel (LTCC). The aim was to demonstrate the role of Rad in intracellular calcium homeostasis by cardiac-Specific dominant-negative suppression of Rad. Transgenic (TG) mice overexpressing dominant-negative mutant Rad (S105N Rad TG) were generated. To measure intracellular Ca(2+) concentration ([Ca(2+)]i), we recorded [Ca(2+)]i transients and Ca(2+) sparks from isolated cardiomyocytes using confocal microscopy. The mean [Ca(2+)]i transient amplitude was significantly increased in S105N Rad TG cardiomyocytes, compared with control littermate mouse cells. The frequency of Ca(2+) sparks was also significantly higher in TG cells than in control cells, although there were no significant differences in amplitude. The sarcoplasmic reticulum Ca(2+) content was not altered in the S105N Rad TG cells, as assessed by measuring caffeine-induced [Ca(2+)]i transient. In contrast, phosphorylation of Ser(2809) on the cardiac ryanodine receptor (RyR2) was significantly enhanced in TG mouse hearts compared with controls. Additionally, the Rad-mediated RyR2 phosphorylation was regulated via a direct interaction of Rad with protein kinase A (PKA).
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Parajuli SP, Provence A, Petkov GV. Prostaglandin E2 excitatory effects on guinea pig urinary bladder smooth muscle: a novel regulatory mechanism mediated by large-conductance voltage- and Ca2+-activated K+ channels. Eur J Pharmacol 2014; 738:179-85. [PMID: 24886877 DOI: 10.1016/j.ejphar.2014.05.042] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Revised: 05/21/2014] [Accepted: 05/23/2014] [Indexed: 02/08/2023]
Abstract
Prostaglandin E2 (PGE2) is an essential signaling molecule involved in the regulation of detrusor smooth muscle (DSM) function. However, the underlying regulatory mechanism by which PGE2 augments DSM cell excitability and contractility is not well understood. Here, we investigated whether PGE2 inhibits the large conductance voltage- and Ca(2+)-activated K(+) (BK) channels in guinea pig DSM, thereby increasing DSM excitability and contractility. We used a multidisciplinary experimental approach including amphotericin-B perforated patch-clamp electrophysiology and live-cell Ca(2+) imaging in native freshly-isolated DSM cells, isometric tension recordings of intact DSM strips, and pharmacological tools to investigate BK channel regulation by PGE2 in guinea pig DSM. PGE2 increased the spontaneous phasic contractions of isolated DSM strips in a concentration-dependent manner (10 nM-10 µM). BK channel inhibition with paxilline (1 µM) attenuated the PGE2-induced DSM phasic contractions, suggesting that BK channels are involved in the mechanism of PGE2-induced DSM contractions. PGE2 (10 µM) increased the intracellular Ca(2+) levels in freshly-isolated DSM cells. PGE2 (10 µM) also caused an inhibition of the amplitude and frequency of spontaneous transient BK currents in DSM cells. Moreover, PGE2 (10 µM) did not affect the amplitude of whole cell steady-state BK currents in DSM cells. Our findings provide strong experimental evidence that PGE2 leads to an inhibition of the spontaneous transient BK currents, elevation of intracellular Ca(2+) levels in freshly-isolated DSM cells, and augmentation of DSM phasic contractions. Thus, we have revealed a novel mechanism that BK channels mediate PGE2-induced contractions in guinea pig DSM.
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Affiliation(s)
- Shankar P Parajuli
- Department of Drug Discovery and Biomedical Sciences, South Carolina College of Pharmacy, University of South Carolina, Coker Life Sciences Building, Room 609D, 715 Sumter St, Columbia, SC 29208, United States
| | - Aaron Provence
- Department of Drug Discovery and Biomedical Sciences, South Carolina College of Pharmacy, University of South Carolina, Coker Life Sciences Building, Room 609D, 715 Sumter St, Columbia, SC 29208, United States
| | - Georgi V Petkov
- Department of Drug Discovery and Biomedical Sciences, South Carolina College of Pharmacy, University of South Carolina, Coker Life Sciences Building, Room 609D, 715 Sumter St, Columbia, SC 29208, United States.
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38
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Zhang Y, Shi ZG, Wang ZH, Li JG, Chen JY, Zhang C. Effects of amyloid β-peptide fragment 31-35 on the BK channel-mediated K⁺ current and intracellular free Ca²⁺ concentration of hippocampal CA1 neurons. Neurosci Lett 2014; 568:72-6. [PMID: 24680749 DOI: 10.1016/j.neulet.2014.03.028] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2013] [Revised: 03/12/2014] [Accepted: 03/19/2014] [Indexed: 12/23/2022]
Abstract
The present study characterizes the effects of Aβ31-35, a short active fragment of amyloid β-peptide (Aβ), upon the BK channel-mediated K⁺ current and intracellular free Ca²⁺ concentration ([Ca²⁺]i) of freshly dissociated pyramidal cells from rat CA1 hippocampus by using whole-cell patch-clamp recording and single cell Ca²⁺ imaging techniques. The results show that: (1) in the presence of voltage- and ATP-gated K⁺ channel blockers application of 5.0 μM Aβ31-35 significantly diminished transient outward K⁺ current amplitudes at clamped voltages between 0 and 45mV; (2) under the same conditions [Ca²⁺]i was minimally affected by 5.0 μM but significantly increased by 12.5 μM and 25 μM Aβ31-35; and (3) when 25 μM of a larger fragment of the amyloid β-peptide, Aβ25-35, was applied, the results were similar to those obtained with the same concentration of Aβ31-35. These results indicate that Aβ31-35 is likely to be the shortest active fragment of the full Aβ sequence, and can be as effectively as the full-length Aβ peptide in suppressing BK-channel mediated K⁺ currents and significantly elevating [Ca²⁺]i in hippocampal CA1 neurons.
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Affiliation(s)
- Yu Zhang
- Department of Neurobiology, Shanxi Key Laboratory of Cell Physiology, Shanxi Medical University, Taiyuan, Shanxi 030001, PR China.
| | - Zhi-Gang Shi
- Department of Neurobiology, Shanxi Key Laboratory of Cell Physiology, Shanxi Medical University, Taiyuan, Shanxi 030001, PR China
| | - Zhi-Hua Wang
- Department of Pathology, Shanxi Medical University, Taiyuan, Shanxi 030001, PR China
| | - Jian-Guo Li
- Department of Neurobiology, Shanxi Key Laboratory of Cell Physiology, Shanxi Medical University, Taiyuan, Shanxi 030001, PR China
| | - Jin-Yuan Chen
- Functional Laboratory, Shanxi Medical University, Taiyuan, Shanxi 030001, PR China
| | - Ce Zhang
- Department of Neurobiology, Shanxi Key Laboratory of Cell Physiology, Shanxi Medical University, Taiyuan, Shanxi 030001, PR China.
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Pfeiffer T, Draguhn A, Reichinnek S, Both M. Optimized temporally deconvolved Ca²⁺ imaging allows identification of spatiotemporal activity patterns of CA1 hippocampal ensembles. Neuroimage 2014; 94:239-49. [PMID: 24650598 DOI: 10.1016/j.neuroimage.2014.03.030] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Revised: 02/07/2014] [Accepted: 03/10/2014] [Indexed: 01/30/2023] Open
Abstract
Hippocampal activity is characterized by the coordinated firing of a subset of neurons. Such neuronal ensembles can either be driven by external stimuli to form new memory traces or be reactivated by intrinsic mechanisms to reactivate and consolidate old memories. Hippocampal network oscillations orchestrate this coherent activity. One key question is how the topology, i.e. the functional connectivity of neuronal networks supports their desired function. Recently, this has been addressed by characterizing the intrinsic properties for the highly recurrently connected CA3 region using organotypic slice cultures and Ca(2+) imaging. In the present study, we aimed to determine the properties of CA1 hippocampal ensembles at high temporal and multiple single cell resolution. Thus, we performed Ca(2+) imaging using the chemical fluorescent Ca(2+) indicator Oregon Green BAPTA 1-AM. To achieve most physiological conditions, we used acute hippocampal slices that were recorded in a so-called interface chamber. To faithfully reconstruct firing patterns of multiple neurons in the field of view, we optimized deconvolution-based detection of action potential associated Ca(2+) events. Our approach outperformed currently available detection algorithms by its sensitivity and robustness. In combination with advanced network analysis, we found that acute hippocampal slices contain a median of 11 CA1 neuronal ensembles with a median size of 4 neurons. This apparently low number of neurons is likely due to the confocal imaging acquisition and therefore yields a lower limit. The distribution of ensemble sizes was compatible with a scale-free topology, as far as can be judged from data with small cell numbers. Interestingly, cells were more tightly clustered in large ensembles than in smaller groups. Together, our data show that spatiotemporal activity patterns of hippocampal neuronal ensembles can be reliably detected with deconvolution-based imaging techniques in mouse hippocampal slices. The here presented techniques are fully applicable to similar studies of distributed optical measurements of neuronal activity (in vivo), where signal-to-noise ratio is critical.
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Kusama-Eguchi K, Miyano T, Yamamoto M, Suda A, Ito Y, Ishige K, Ishii M, Ogawa Y, Watanabe K, Ikegami F, Kusama T. New insights into the mechanism of neurolathyrism: L-β-ODAP triggers [Ca2+]i accumulation and cell death in primary motor neurons through transient receptor potential channels and metabotropic glutamate receptors. Food Chem Toxicol 2014; 67:113-22. [PMID: 24582715 DOI: 10.1016/j.fct.2014.02.021] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2013] [Revised: 01/07/2014] [Accepted: 02/17/2014] [Indexed: 10/25/2022]
Abstract
Neurolathyrism is a motor neuron (MN) disease caused by β-N-oxalyl-L-α,β-diaminopropionic acid (L-β-ODAP), an AMPA receptor agonist. L-β-ODAP caused a prolonged rise of intracellular Ca(2+) ([Ca(2+)]i) in rat spinal cord MNs, and the [Ca(2+)]i accumulation was inversely proportional to the MN's life span. The [Ca(2+)]i rise induced by L-β-ODAP or (S)-AMPA was antagonized completely by NBQX, an AMPA-receptor blocker. However, blocking the L-type Ca(2+) channel with nifedipine significantly lowered [Ca(2+)]i induced by (S)-AMPA, but not that by L-β-ODAP. Tetrodotoxin completely extinguished the [Ca(2+)]i rise induced by (S)-AMPA or kainic acid, whereas that induced by L-β-ODAP was only attenuated by 65.6±6% indicating the prominent involvement of voltage-independent Ca(2+) entry. The tetrodotoxin-resistant [Ca(2+)]i induced by L-β-ODAP was blocked by 2-APB, Gd(3+), La(3+), 1-(β-[3-(4-methoxy-phenyl)propoxy]-4-methoxyphenethyl)-1H-imidazole hydrochloride (SKF-96365) and flufenamic acid, which all are blockers of the transient receptor potential (TRP) channels. Blockers of group I metabotropic glutamate receptors (mGluR I), 7-(hydroxyiminocyclopropan[b]chromen-1α-carboxylate ethyl ester (CPCCPEt) and 2-methyl-6-(phenylethynyl)-pyridine (MPEP) also lowered the [Ca(2+)]i rise by L-β-ODAP. MN cell death induced by L-β-ODAP was prolonged significantly with SKF-96365 as well as NBQX. The results show the involvement of TRPs and mGluR I in L-β-ODAP-induced MN toxicity through prolonged [Ca(2+)]i mobilization, a unique characteristic of this neurotoxin.
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Affiliation(s)
- Kuniko Kusama-Eguchi
- Laboratory of Biochemistry, School of Pharmacy, Nihon University, Narashinodai 7-7-1, Funabashi 274-8555, Japan; Laboratory of Molecular Cell Biology, School of Pharmacy, Nihon University, Narashinodai 7-7-1, Funabashi 274-8555, Japan
| | - Takaaki Miyano
- Laboratory of Molecular Cell Biology, School of Pharmacy, Nihon University, Narashinodai 7-7-1, Funabashi 274-8555, Japan
| | - Makoto Yamamoto
- Laboratory of Molecular Cell Biology, School of Pharmacy, Nihon University, Narashinodai 7-7-1, Funabashi 274-8555, Japan; Laboratory of Pharmacology, School of Pharmacy, Nihon University, Narashinodai 7-7-1, Funabashi 274-8555, Japan
| | - Atsuhiro Suda
- Laboratory of Molecular Cell Biology, School of Pharmacy, Nihon University, Narashinodai 7-7-1, Funabashi 274-8555, Japan
| | - Yoshihisa Ito
- Laboratory of Pharmacology, School of Pharmacy, Nihon University, Narashinodai 7-7-1, Funabashi 274-8555, Japan
| | - Kumiko Ishige
- Laboratory of Pharmacology, School of Pharmacy, Nihon University, Narashinodai 7-7-1, Funabashi 274-8555, Japan
| | - Mayuko Ishii
- Laboratory of Biochemistry, School of Pharmacy, Nihon University, Narashinodai 7-7-1, Funabashi 274-8555, Japan
| | - Yoshio Ogawa
- Laboratory of Molecular Cell Biology, School of Pharmacy, Nihon University, Narashinodai 7-7-1, Funabashi 274-8555, Japan
| | - Kazuko Watanabe
- Laboratory of Molecular Cell Biology, School of Pharmacy, Nihon University, Narashinodai 7-7-1, Funabashi 274-8555, Japan
| | - Fumio Ikegami
- Center for Environment, Health and Field Sciences, Chiba University, Kashiwanoha 6-2-1, Kashiwa 277-0822, Japan
| | - Tadashi Kusama
- Laboratory of Physiology and Anatomy, School of Pharmacy, Nihon University, Narashinodai 7-7-1, Funabashi 274-8555, Japan
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Visser D, Langeslag M, Kedziora KM, Klarenbeek J, Kamermans A, Horgen FD, Fleig A, van Leeuwen FN, Jalink K. TRPM7 triggers Ca2+ sparks and invadosome formation in neuroblastoma cells. Cell Calcium 2013; 54:404-15. [PMID: 24176224 DOI: 10.1016/j.ceca.2013.09.003] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2013] [Revised: 09/27/2013] [Accepted: 09/28/2013] [Indexed: 11/28/2022]
Abstract
Cell migration depends on the dynamic formation and turnover of cell adhesions and is tightly controlled by actomyosin contractility and local Ca2+ signals. The divalent cation channel TRPM7 (Transient Receptor Potential cation channel, subfamily Melastatin, member 7) has recently received much attention as a regulator of cell adhesion, migration and (localized) Ca2+ signaling. Overexpression and knockdown of TRPM7 affects actomyosin contractility and the formation of cell adhesions such as invadosomes and focal adhesions, but the role of TRPM7-mediated Ca2+ signals herein is currently not understood. Using Total Internal Reflection Fluorescence (TIRF) Ca2+ fluorometry and a novel automated analysis routine we have addressed the role of Ca2+ in the control of invadosome dynamics in N1E-115 mouse neuroblastoma cells. We find that TRPM7 promotes the formation of highly repetitive and localized Ca2+ microdomains or "Ca2+ sparking hotspots" at the ventral plasma membrane. Ca2+ sparking appears strictly dependent on extracellular Ca2+ and is abolished by TRPM7 channel inhibitors such as waixenicin-A. TRPM7 inhibition also induces invadosome dissolution. However, invadosome formation is (functionally and spatially) dissociated from TRPM7-mediated Ca2+ sparks. Rather, our data indicate that TRPM7 affects actomyosin contractility and invadosome formation independent of Ca2+ influx.
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Affiliation(s)
- Daan Visser
- Division of Cell Biology I, The Netherlands Cancer Institute, 1066 CX Amsterdam, The Netherlands
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42
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Turovsky EA, Turovskaya MV, Kononov AV, Zinchenko VP. Short-term episodes of hypoxia induce posthypoxic hyperexcitability and selective death of GABAergic hippocampal neurons. Exp Neurol 2013; 250:1-7. [PMID: 24041985 DOI: 10.1016/j.expneurol.2013.09.006] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2013] [Revised: 08/07/2013] [Accepted: 09/09/2013] [Indexed: 10/26/2022]
Abstract
We have previously developed a rat hippocampal neuronal cell model for the registration of the preconditioning effect and posthypoxic hyperexcitability (Turovskaya et al., 2011). Repeated episodes of short-term hypoxia are reported to suppress the amplitude of Ca(2+) response to NMDA in majority of neurons, reflecting the effect of preconditioning in the culture. In addition, exposure to hypoxia causes posthypoxic hyperexcitability: this is characterized by the onset of spontaneous synchronous Ca(2+) transients in a population of neurons in a neural network during the period of reoxygenation after each hypoxic episode. The nature of this phenomenon is unknown, although it has been observed that there always exists a minority of neurons in which there is no effect of hypoxic preconditioning. In this small population of neurons, the amplitude of Ca(2+) response to NMDA is not suppressed, but rather increases after each episode of hypoxia. Here we report the type of these neurons and their role in the generation of posthypoxic hyperexcitability. We compared the effect of short-term hypoxia on the amplitude of the Ca(2+) response to NMDA and the Ca(2+) transient generation in two populations of neurons - inhibitory GABAergic and excitatory glutamatergic. We have demonstrated that the neurons in which the preconditioning effect was not observed are GABAergic. Moreover at the instant moment of the posthypoxic synchronous Ca(2+)-transient generation (during reoxygenation) there is a global increase of [Ca(2+)]i and subsequent apoptosis in some GABAergic neurons. Anti-inflammatory cytokine interleukin-10 prevents the development of posthypoxic hyperexcitability, inhibiting the spontaneous synchronous Ca(2+) transients. At the same time, interleukin-10 protects GABAergic neurons from death, by restoring the effect of hypoxic preconditioning in them. Activation of one of the signaling pathways initiated by interleukin-10 appears to be necessary for the development of hypoxic preconditioning in GABAergic neurons. Overall our results indicate that short-term episodes of hypoxia can damage GABAergic neurons and weaken the inhibitory action of GABAergic neurons in a neural network. Activation of PI3K-dependent survival signaling pathways in neurons of this type is a possible strategy to protect these cells against hypoxia.
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Affiliation(s)
- Egor A Turovsky
- Institute of Cell Biophysics, Russian Academy of Sciences, Pushchino, Russia
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Kim MH, Seo JB, Burnett LA, Hille B, Koh DS. Characterization of store-operated Ca2+ channels in pancreatic duct epithelia. Cell Calcium 2013; 54:266-75. [PMID: 23968882 DOI: 10.1016/j.ceca.2013.07.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2013] [Revised: 07/18/2013] [Accepted: 07/20/2013] [Indexed: 11/30/2022]
Abstract
Store-operated Ca2+ channels (SOCs) are activated by depletion of intracellular Ca2+ stores following agonist-mediated Ca2+ release. Previously we demonstrated that Ca2+ influx through SOCs elicits exocytosis efficiently in pancreatic duct epithelial cells (PDEC). Here we describe the biophysical, pharmacological, and molecular properties of the duct epithelial SOCs using Ca2+ imaging, whole-cell patch-clamp, and molecular biology. In PDEC, agonists of purinergic, muscarinic, and adrenergic receptors coupled to phospholipase C activated SOC-mediated Ca2+ influx as Ca2+ was released from intracellular stores. Direct measurement of [Ca2+] in the ER showed that SOCs greatly slowed depletion of the ER. Using IP3 or thapsigargin in the patch pipette elicited inwardly rectifying SOC currents. The currents increased ∼8-fold after removal of extracellular divalent cations, suggesting competitive permeation between mono- and divalent cations. The current was completely blocked by high doses of La3+ and 2-aminoethoxydiphenyl borate (2-APB) but only partially depressed by SKF-96365. In polarized PDEC, SOCs were localized specifically to the basolateral membrane. RT-PCR screening revealed the expression of both STIM and Orai proteins for the formation of SOCs in PDEC. By expression of fluorescent STIM1 and Orai1 proteins in PDEC, we confirmed that colocalization of the two proteins increases after store depletion. In conclusion, basolateral Ca2+ entry through SOCs fills internal Ca2+ stores depleted by external stimuli and will facilitate cellular processes dependent on cytoplasmic Ca2+ such as salt and mucin secretion from the exocrine pancreatic ducts.
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Affiliation(s)
- Mean-Hwan Kim
- Department of Physics, Pohang University of Science and Technology, Pohang, Republic of Korea
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