Physiological and Pharmacological Characteristics of Quisqualic Acid-Induced K؉-Current Response in the Ganglion Cells of Aplysia

Total Page:16

File Type:pdf, Size:1020Kb

Physiological and Pharmacological Characteristics of Quisqualic Acid-Induced K؉-Current Response in the Ganglion Cells of Aplysia Japanese Journal of Physiology, 51, 511–521, 2001 Physiological and Pharmacological Characteristics of Quisqualic Acid-Induced K1-Current Response in the Ganglion Cells of Aplysia Shingo KIMURA, Satoshi KAWASAKI, Koichiro TAKASHIMA, and Kazuhiko SASAKI Department of Physiology and Advanced Medical Science Research Center, School of Medicine, Iwate Medical University, Morioka, 020–8505 Japan Abstract: The extracellular application of ei- the application of either kainate or AMPA, ago- ther quisqualic acid (QA) or Phe-Met-Arg-Phe- nists for non-NMDA receptors, produced no type NH2 (FMRFamide) induces an outward current in of response in the same neurons. The QA-in- identified neurons of Aplysia ganglion under volt- duced K1-current response was not depressed age clamp. The time course of the QA-induced at all by an intracellular injection of either gua- response is significantly slower than that induced nosine 59-O-(2-thiodiphosphate) (GDP-bS) or by FMRFamide. The reversal potential for both guanosine 59-O-(3-thiotriphosphate) (GTP-gS), responses was 292 mV and was shifted 17 mV but the FMRFamide-induced response was in a positive direction for a twofold increase in markedly blocked by both GDP-bS and GTP-gS the extracellular K1 concentration. The QA-in- in the same cell. Furthermore, the QA- and FMR- duced response was markedly depressed in the Famide-induced K1-current responses were both presence of Ba21, a blocker of inward rectifier decreased markedly when the temperature was K1-channel, whereas TEA, a Ca21-activated K1- lowered to 15°C, from 23°C. These results sug- 1 1 channel (BKCa) blocker, or 4-AP, a transient K gested that the QA-induced K -current response (A)-channel blocker, had no effect on the re- is produced by an activation of a novel type of sponse. The QA-induced K1-current was signifi- QA-receptor and that this response is not pro- cantly suppressed by CNQX and GYKI52466, duced by an activation of the G protein. [Japa- antagonists of non-NMDA receptors. However, nese Journal of Physiology, 51, 511–521, 2001] Key words: quisqualic acid, glutamate receptor, molluscan neuron, potassium channel. Glutamate is a major neurotransmitter for excitatory tic potentials are produced by the activation of synaptic transmission in the central nervous system ionotropic glutamate receptors (iGluRs), which con- (CNS) of the vertebrate and the invertebrate. Besides sist of receptor–cation channel complexes as revealed producing the fast excitatory synaptic potentials in the by cDNA cloning. The iGluRs have been subdivided CNS, the glutamatergic synapse plays an important into the NMDA-, AMPA-, and kainate-receptor sub- role in the formation of synaptic plasticity, such as types by their pharmacological profiles [1]. Glutamate learning and memory. An excessive release of gluta- can also activate metabotropic glutamate receptors mate from the synaptic terminal is thought to be one (mGluRs), which are coupled to G proteins and a sub- cause for apoptosis, neuronal death. Glutamatergic sequent intracellular messenger system, such as phos- synaptic transmission is also important for the under- phatidyl inositol (PI) turnover. Usually an activation standing of various neuronal diseases. of the mGluRs produces slow synaptic potentials and In glutamatergic synapse, fast excitatory postsynap- primarily mediates the modulatory function of the cell Received on February 21, 2001; accepted on June 11, 2001 Correspondence should be addressed to: Shingo Kimura, Department of Physiology and Advanced Medical Science Research Center, School. of Medicine, Iwate Medical University, Uchimaru 19–1, Morioka, 020–8505 Japan. Tel: 181–19–651–5111 ext 3344, Fax: 181–19– 625–3447, E-mail: [email protected] Japanese Journal of Physiology Vol. 51, No. 4, 2001 511 S. KIMURA et al. response. At least eight subtypes of mGluRs in mam- (QA)-receptor that is quite different from those of malian CNS, termed as mGluR1–mGluR8, have been mammalian neurons. Furthermore, this response is identified by cDNA cloning [2]. produced by an increase in K1 permeability without In invertebrate neurons, the application of gluta- activation of the G protein, but it is possibly regulated mate induces an excitatory response similar to the ver- by a certain enzymatic process. tebrate neurons [3, 4]. Furthermore, inhibitory re- sponses are also induced by the stimulation of another METHODS type of glutamate receptor in molluscan neurons (see review by Cleland [5]). For instance, in the neurons of Preparation and perfusion media. The buc- Planorbarius corneus and Aplysia californica, an ap- cal ganglion or abdominal ganglion was isolated from plication of glutamate produces a hyperpolarizing re- Aplysia kurodai and fixed in a perfusing chamber. The sponse because of the opening of the Cl2-channel [6, connective tissues covering the caudal surface of the 7]. Furthermore, Bolshakov et al. [8], Katz and Levi- buccal ganglion or the dorsal surface of the abdominal tan [9], Kehoe [10], and Watanabe et al. [11] have re- ganglion were carefully removed under a dissecting ported other types of hyperpolarizing responses pro- microscope to expose the cells to the perfusing duced by an increase in K1 conductance after receptor medium. Neurons of the buccal ganglia responded to stimulation in the neurons of Planorbarius corneus, either QA or FMRFamide, but not to GABA, whereas Aplysia californica, and Euhadra peliomphala. neurons of the abdominal ganglia responded to GABA We previously hypothesized that most of the recep- and FMRFamide, but not to QA. We therefore used tor-induced K1-current responses are produced by an the buccal ganglia in most experiments, except the activation of the common G protein, Gi or Go, regard- temperature dependence of the GABA-induced re- less of their receptor types, based on experimental evi- sponse. The artificial Aplysia serum solution con- dence [12]. Actually, recent studies on invertebrates tained (in mM) NaCl, 587; MgCl2, 52; KCl, 11.5; 1 neurons have demonstrated that a slow K -current re- CaCl2, 14; and Tris, 50.1 (pH 7.4) [15]. The cells were sponse induced by glutamate is mediated by pertussis continuously perfused at a constant flow rate of toxin (PTX)-sensitive G protein activation [8]. Studies 5 ml/min and at a temperature of 2362°C. The effec- of some vertebrate neurons have also shown that glu- tive perfusing volume of the chamber was 0.2 ml. tamate evokes a hyperpolarizing response as a result Electrical measurements. Two microelec- of the activation of PTX-sensitive G protein. For ex- trodes filled with 1.8 M potassium citrate with a resis- ample, Holmes et al. have shown that the activation of tance of 5 to 7 MV were inserted into a single cell. Ei- 21 1 Ca -activated K channels (BKCa channel) through a ther the current- or voltage-clamp method was used to group II mGluR is linked to a PTX-sensitive G pro- evaluate the response of the neurons to the bath-ap- tein in basolateral amygdala neurons of rat [13]. plied agonists. The membrane potential was usually Knoflach and Kemp have also reported that a group II held at 265 mV, which was close to the resting poten- mGluR-induced hyperpolarizing response produced tial of the cells studied. To evaluate the change in by an opening of the inward rectifying K1 channel is membrane slope conductance, repetitive 1 s, 5 to coupled to G protein in rat cerebellum neuron, though 10 nA current pulses or 3 to 6 mV voltage pulses at the type of G protein involved in this response is not 0.2 Hz were applied across the cell membrane in the yet identified [14]. current- or voltage-clamp methods, respectively. On the other hand, Kehoe [10] and Watanabe et al. Drug application. Drugs used were L-glutamic [11] demonstrated in molluscan neurons that gluta- acid (Kanto Chemical); quisqualic acid (QA, Sigma); 1 mate produces an outward K -current response, Phe-Met-Arg-Phe-NH2 (FMRFamide, Peptide Insti- which does not appear to be mediated by G protein. tute); g-aminobutyric acid (GABA, Wako); N-methyl- However, pharmacological properties and the mecha- D-aspartic acid (NMDA, RBI); (6)-a-amino-3-hy- nism involved in ionic channel gating in this type of droxy-5-methylisoxazole-4-propionic acid (AMPA, glutamate receptor response have not been studied in RBI); 2-carboxy-4-(1-methyl-ethenyl)-3-pyrrolidin- detail. acetic acid (kainate, RBI); trans-(6)-1-amino- In this paper, we studied physiological and pharma- (1S,3R)-cyclopentanedicarboxylic acid (transACPD, cological characteristics of the slow hyperpolarizing RBI); trans-2,4-azetidine-dicarboxylic acid (tADA, response to stimulation of the glutamate receptor in RBI); L(1)-2-amino-4-phosphonobutyric acid (L- the identified neurons of the buccal ganglion of AP4, RBI); (6)-2-amino-5-phosphonopentanoic acid Aplysia. We report that this type of glutamate receptor (AP-5, RBI); 6-cyano-7-nitroquinoxaline-2,3-dione: belongs to a novel subtype of quisqualic acid HBC complex (CNQX, RBI); 1-(4-aminophenyl)-4- 512 Japanese Journal of Physiology Vol. 51, No. 4, 2001 Quisqualic Acid–Induced K1-Current methyl-7,8-methylenedioxy-5H-2,3-benzodiazepine RESULTS hydrochloride (GYKI52466, RBI); (6)-a-amino- 4-carboxy-a-methyl-benzeneacetic acid ((6)MCPG, Characteristics of quisqualic acid–induced RBI); R(1)-2-amino-3-phosphonopropanoic acid 3- response phosphono-L-alanine (L(1)-AP-3, RBI); guano- In current-clamp experiments, the application of ei- sine 59-O-(2-thiodiphosphate) (GDP-bS, Boehringer ther quisqualic acid (QA) or Phe-Met-Arg-Phe-NH2 Mannheim); guanosine 59-O-(3-thiotriphosphate) (FMRFamide) induces a slow hyperpolarizing re- (GTP-gS, Boehringer Mannheim); ethyleneglycol-bis- sponse associated with a decrease in membrane resis- (b-aminoethylether)N,N,N9,N9-tetraacetic acid (EGTA, tance in both BR6 and BL6 cells [16, 17] of the buc- Dojin); tetraethylammonium (TEA, Kanto Chemical); cal ganglion of Aplysia (Fig.
Recommended publications
  • Download Product Insert (PDF)
    Product Information CNQX Item No. 14618 CAS Registry No.: 115066-14-3 Formal Name: 1,2,3,4-tetrahydro-7-nitro-2,3-dioxo-6- quinoxalinecarbonitrile H Synonyms: 6-cyano-7-Nitroquinoxaline-2,3-dione, NC N O FG 9065 MF: C9H4N4O4 FW: 232.2 O O N N Purity: ≥98% 2 Stability: ≥2 years at -20°C H Supplied as: A crystalline solid λ UV/Vis.: max: 217, 275, 315 nm Laboratory Procedures For long term storage, we suggest that CNQX be stored as supplied at -20°C. It should be stable for at least two years. CNQX is supplied as a crystalline solid. A stock solution may be made by dissolving the CNQX in the solvent of choice. CNQX is soluble in organic solvents such as DMSO and dimethyl formamide (DMF), which should be purged with an inert gas. The solubility of CNQX in these solvents is approximately 5 and 12 mg/ml, respectively. CNQX is sparingly soluble in aqueous buffers. For maximum solubility in aqueous buffers, CNQX should first be dissolved in DMF and then diluted with the aqueous buffer of choice. CNQX has a solubility of approximately 0.5 mg/ml in a 1:1 solution of DMF:PBS (pH 7.2) using this method. We do not recommend storing the aqueous solution for more than one day. CNQX is a competitive, non-NMDA glutamate receptor antagonist (IC50s = 0.3 and 1.5 μM for AMPA and kainate 1,2 receptors, respectively, versus IC50 = 25 μM for NMDA receptors). This compound has been used to specifically target AMPA and kainate receptor responses and thus differentiate from that of NMDA receptors.
    [Show full text]
  • Switch to Tonic Discharge by Thyrotropin-Releasing Hormone
    Neuron Article Synchronized Network Oscillations in Rat Tuberoinfundibular Dopamine Neurons: Switch to Tonic Discharge by Thyrotropin-Releasing Hormone David J. Lyons,1,* Emilia Horjales-Araujo,1 and Christian Broberger1,* 1Department of Neuroscience, Karolinska Institutet, 171 77 Stockholm, Sweden *Correspondence: [email protected] (D.J.L.), [email protected] (C.B.) DOI 10.1016/j.neuron.2009.12.024 SUMMARY most common form of pituitary tumor (Burrow et al., 1981), and by the hyperprolactinaemia and sometimes galactorrhea that The pituitary hormone, prolactin, triggers lactation in is a side effect of antipsychotic drugs with DA antagonist prop- nursing mothers. Under nonlactating conditions, erties (Clemens et al., 1974; Meltzer and Fang, 1976). Yet, to prolactin secretion is suppressed by powerful inhibi- date, the cellular and network electrophysiological properties tion from hypothalamic tuberoinfundibular dopamine of the TIDA cell population have not been described. These (TIDA) neurons. Although firing pattern has been sug- factors are potentially fundamental features of prolactin regula- gested as integral to neuroendocrine control, the tion since discharge pattern may determine the functional output of neuroendocrine control of the anterior pituitary, as is observed electrical behavior of TIDA cells remains unknown. in the magnocellular system (Wakerley and Lincoln, 1973; Hatton We demonstrate that rat TIDA neurons discharge et al., 1983). Thus, the periodic bursting pattern in hypothalamic rhythmically in a robust 0.05 Hz oscillation. The oscil- gonadotropin-releasing hormone neurons is required for stimu- lation is phase locked between neurons, and while it lation of target gonadotrophs in the pituitary (Knobil, 1980). persists during chemical synaptic transmission When bursting is artificially replaced by continuous agonist stim- blockade, it is abolished by gap junction antagonists.
    [Show full text]
  • Isoflurane Inhibits Dopaminergic Synaptic Vesicle Exocytosis Coupled to Cav2.1 and Cav2.2 in Rat Midbrain Neurons
    This Accepted Manuscript has not been copyedited and formatted. The final version may differ from this version. Research Article: New Research | Neuronal Excitability Isoflurane inhibits dopaminergic synaptic vesicle exocytosis coupled to CaV2.1 and CaV2.2 in rat midbrain neurons Christina L. Torturo1,2, Zhen-Yu Zhou1, Timothy A. Ryan1,3 and Hugh C. Hemmings1,2 1Departments of Anesthesiology, Weill Cornell Medicine, New York, NY 10065 2Pharmacology, Weill Cornell Medicine, New York, NY 10065 3Biochemistry, Weill Cornell Medicine, New York, NY 10065 https://doi.org/10.1523/ENEURO.0278-18.2018 Received: 16 July 2018 Revised: 18 December 2018 Accepted: 21 December 2018 Published: 10 January 2019 Author Contributions: CLT, ZZ, TAR and HCH designed the research; CLT performed the research, TAR contributed unpublished reagents/analytic tools; CLT and ZZ analyzed the data; CLT, ZZ, TAR, and HCH wrote the paper. Funding: http://doi.org/10.13039/100000002HHS | National Institutes of Health (NIH) GM58055 Conflict of Interest: HCH: Editor-in-Chief of the British Journal of Anaesthesia; consultant for Elsevier. Funding Sources: NIH GM58055 Corresponding author: Hugh C. Hemmings, E-mail: [email protected] Cite as: eNeuro 2019; 10.1523/ENEURO.0278-18.2018 Alerts: Sign up at www.eneuro.org/alerts to receive customized email alerts when the fully formatted version of this article is published. Accepted manuscripts are peer-reviewed but have not been through the copyediting, formatting, or proofreading process. Copyright © 2019 Torturo et al. This is an open-access article distributed under the terms of the Creative Commons Attribution 4.0 International license, which permits unrestricted use, distribution and reproduction in any medium provided that the original work is properly attributed.
    [Show full text]
  • Excitatory Amino Acid Β-N-Methylamino-L-Alanine Is a Putative
    J. Serb. Chem. Soc. 76 (4) 479–490 (2011) UDC 547.466.23+547.416:616.8+ JSCS–4134 620.266.1:628.513 Review REVIEW Excitatory amino acid β-N-methylamino-L-alanine is a putative environmental neurotoxin SRDJAN LOPIČIĆ1*, MARIJA BRATIĆ-STANOJEVIĆ1, PATHAK DHRUBA1, DRAGAN PAVLOVIĆ2, MILICA PROSTRAN3 and VLADIMIR NEDELJKOV1 1Institute for Pathological Physiology, School of Medicine, University of Belgrade, 11000 Belgrade, Serbia, 2Ernst Moritz Arndt University, Greifswald, Germany and 3Institute of Pharmacology, Clinical Pharmacology and Toxicology, School of Medicine, University of Belgrade, 11000 Belgrade, Serbia (Received 29 July, revised 4 October 2010) Abstract: The amino acid β-N-methylamino-L-alanine (L-BMAA) has been associated with the amyotrophic lateral sclerosis/parkinsonism-dementia complex in three distinct western Pacific populations. The putative neurotoxin is produced by cyanobacteria, which live symbiotically in the roots of cycad trees. L-BMAA was thought to be a threat only to those few populations whose diet and medicines rely heavily on cycad seeds. However, the recent discovery that cyanobacteria from diverse terrestrial, freshwater, and saltwater ecosys- tems around the world produce the toxin requires a reassessment of whether it poses a larger health threat. Therefore, it is proposed that monitoring L-BMAA levels in cyanobacteria-contaminated water supplies might be prudent. Keywords: β-N-methylamino-L-alanine; neurodegenerative diseases; neuro- toxicity; environmental toxin. CONTENTS 1. INTRODUCTION 2. THE BMAA NEUROTOXICITY 3. MECHANISMS OF BMAA NEUROTOXICITY 4. BMAA AND THE ENVIRONMENT 5. CONCLUSIONS 1. INTRODUCTION It has been well established that cyanobacterial and other environmental toxins cause and/or promote the development of a vast variety of diseases and * Corresponding author.
    [Show full text]
  • Ion Channels
    UC Davis UC Davis Previously Published Works Title THE CONCISE GUIDE TO PHARMACOLOGY 2019/20: Ion channels. Permalink https://escholarship.org/uc/item/1442g5hg Journal British journal of pharmacology, 176 Suppl 1(S1) ISSN 0007-1188 Authors Alexander, Stephen PH Mathie, Alistair Peters, John A et al. Publication Date 2019-12-01 DOI 10.1111/bph.14749 License https://creativecommons.org/licenses/by/4.0/ 4.0 Peer reviewed eScholarship.org Powered by the California Digital Library University of California S.P.H. Alexander et al. The Concise Guide to PHARMACOLOGY 2019/20: Ion channels. British Journal of Pharmacology (2019) 176, S142–S228 THE CONCISE GUIDE TO PHARMACOLOGY 2019/20: Ion channels Stephen PH Alexander1 , Alistair Mathie2 ,JohnAPeters3 , Emma L Veale2 , Jörg Striessnig4 , Eamonn Kelly5, Jane F Armstrong6 , Elena Faccenda6 ,SimonDHarding6 ,AdamJPawson6 , Joanna L Sharman6 , Christopher Southan6 , Jamie A Davies6 and CGTP Collaborators 1School of Life Sciences, University of Nottingham Medical School, Nottingham, NG7 2UH, UK 2Medway School of Pharmacy, The Universities of Greenwich and Kent at Medway, Anson Building, Central Avenue, Chatham Maritime, Chatham, Kent, ME4 4TB, UK 3Neuroscience Division, Medical Education Institute, Ninewells Hospital and Medical School, University of Dundee, Dundee, DD1 9SY, UK 4Pharmacology and Toxicology, Institute of Pharmacy, University of Innsbruck, A-6020 Innsbruck, Austria 5School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, BS8 1TD, UK 6Centre for Discovery Brain Science, University of Edinburgh, Edinburgh, EH8 9XD, UK Abstract The Concise Guide to PHARMACOLOGY 2019/20 is the fourth in this series of biennial publications. The Concise Guide provides concise overviews of the key properties of nearly 1800 human drug targets with an emphasis on selective pharmacology (where available), plus links to the open access knowledgebase source of drug targets and their ligands (www.guidetopharmacology.org), which provides more detailed views of target and ligand properties.
    [Show full text]
  • Microglial Glutathione and Glutamate: Regulation Mechanisms
    Microglial glutathione and glutamate: Regulation mechanisms Victoria Anne Honey Fry UCL Institute of Neurology A thesis submitted for the degree of Doctor of Philosophy (Ph.D.) 1 I, Victoria Fry, confirm that the work presented in this thesis is my own. Where information has been derived from other sources, I confirm that this has been indicated in the thesis. 2 Abstract Microglia, the immune cells of the central nervous system (CNS), are important in the protection of the CNS, but may be implicated in the pathogenesis of neuroinflammatory disease. Upon activation, microglia produce reactive oxygen and nitrogen species; intracellular antioxidants are therefore likely to be important in their self-defence. Here, it was confirmed that cultured microglia contain high levels of glutathione, the predominant intracellular antioxidant in mammalian cells. The activation of microglia with lipopolysaccharide (LPS) or LPS + interferon- was shown to affect their glutathione levels. GSH levels in primary microglia and those of the BV-2 cell line increased upon activation, whilst levels in N9 microglial cells decreased. - Microglial glutathione synthesis is dependent upon cystine uptake via the xc transporter, which exchanges cystine and glutamate. Glutamate is an excitatory neurotransmitter whose extracellular concentration is tightly regulated by excitatory amino acid transporters, as high levels cause toxicity to neurones and other CNS cell types through overstimulation of - glutamate receptors or by causing reversal of xc transporters. Following exposure to LPS, increased extracellular glutamate and increased levels of messenger ribonucleic acid - (mRNA) for xCT, the specific subunit of xc , were observed in BV-2 and primary microglial cells, suggesting upregulated GSH synthesis.
    [Show full text]
  • Nitric Oxide Modulates HCN Channels in Magnocellular Neurons of the Supraoptic Nucleus of Rats by an S-Nitrosylation-Dependent Mechanism
    11320 • The Journal of Neuroscience, November 2, 2016 • 36(44):11320–11330 Cellular/Molecular Nitric Oxide Modulates HCN Channels in Magnocellular Neurons of the Supraoptic Nucleus of Rats by an S-Nitrosylation-Dependent Mechanism X Melina Pires da Silva,1 Davi Jose´ de Almeida Moraes,1 Andre´ de Souza Mecawi,2 Jose´ Antunes Rodrigues,1 and X Wamberto Antonio Varanda1 1Department of Physiology, Ribeira˜o Preto Medical School, University of Sa˜o Paulo, 14049-900 Ribeira˜o Preto, Sa˜o Paulo, Brazil, and 2Department of Physiological Sciences, Biology Institute, Federal Rural University of Rio de Janeiro, 23890-000, Serope´dica, Rio de Janeiro, Brazil The control of the excitability in magnocellular neurosecretory cells (MNCs) of the supraoptic nucleus has been attributed mainly to synapticinputsfromcircunventricularorgans.However,nitricoxide(NO),agaseousmessengerproducedinthisnucleusduringisotonic and short-term hypertonic conditions, is an example of a modulator that can act directly on MNCs to modulate their firing rate. NO inhibits the electrical excitability of MNCs, leading to a decrease in the release of vasopressin and oxytocin. Although the effects of NO on MNCs are well established, the mechanism by which this gas produces its effect is, so far, unknown. Because NO acts independently of synaptic inputs, we hypothesized that ion channels present in MNCs are the targets of NO. To investigate this hypothesis, we used the patch-clamptechniqueinvitroandinsitutomeasurecurrentscarriedbyhyperpolarization-activatedandnucleotide-gatedcation(HCN) channelsandestablishtheirroleindeterminingtheelectricalexcitabilityofMNCsinrats.OurresultsshowthatblockadeofHCNchannels by ZD7288 decreases MNC firing rate with significant consequences on the release of OT and VP, measured by radioimmunoassay. NO induced a significant reduction in HCN currents by binding to cysteine residues and forming S-nitrosothiol complexes.
    [Show full text]
  • Cell Type-Specific Pharmacology of NMDA Receptors Using Masked MK801 Yunlei Yang†, Peter Lee, Scott M Sternson*
    SHORT REPORT elifesciences.org Cell type-specific pharmacology of NMDA receptors using masked MK801 Yunlei Yang†, Peter Lee, Scott M Sternson* Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States Abstract N-Methyl-D-aspartate receptors (NMDA-Rs) are ion channels that are important for synaptic plasticity, which is involved in learning and drug addiction. We show enzymatic targeting of an NMDA-R antagonist, MK801, to a molecularly defined neuronal population with the cell-type-selectivity of genetic methods and the temporal control of pharmacology. We find that NMDA-Rs on dopamine neurons are necessary for cocaine-induced synaptic potentiation, demonstrating that cell type-specific pharmacology can be used to dissect signaling pathways within complex brain circuits. DOI: 10.7554/eLife.10206.001 Introduction N-Methyl-D-aspartate receptors (NMDA-Rs) are glutamate-gated ion channels that are critical for the regulation of synaptic functions in the central nervous system, such as synaptic plasticity (Malenka and Nicoll, 1993; Collingridge et al., 2004). NMDA-R dependent synaptic plasticity plays an important role in learning. This includes learning that can also have maladaptive consequences, for example *For correspondence: sensitization of drug-related behaviors (Kalivas and Alesdatter, 1993; Ungless et al., 2001). However, [email protected] because NMDA-Rs are expressed in most cell types in the brain (Conti et al., 1997; Verkhratsky and † Present address: Department of Kirchhoff, 2007), it is a considerable challenge to selectively assess the importance of NMDA-R Neuroscience and Physiology, mediated synaptic plasticity in specific cell types. State University of New York The functional contribution of NMDA-Rs to physiology and behavior can be examined using either Upstate Medical University, genetic or pharmacological methods.
    [Show full text]
  • Pharmacological Approaches to the Treatment of Ischaemic Neuronal Damage
    Ey e (1991) 5, 193-197 Pharmacological Approaches to the Treatment of Ischaemic Neuronal Damage L. L. IVERSEN Harlow Summary Retina is particularly susceptible to ischaemic damage following exposure to anoxia or hypoglycaemia. In animal models the neuronal damage following ischaemia resembles that caused by exposure to glutamate or other excitotoxic agents which act on excitatory amino acid receptors. There are a number of pharmacological approaches designed to limit neuronal damage following ischaemia. These include free radical scavenging agents, calcium channel blockers, kappa opiate agonists and excitatory amino acid antagonists. Recent studies with antagonists acting at both NMDA and non-NMDA receptors for glutamate show that such compounds can pro­ tect against ischaemic damage, and are effective even when administered several hours after the ischaemic insult. Retinal neurones, like those in other regions systemic administration of L-glutamate or of CNS, are highly dependent on the oxida­ aspartate in very large doses (2-4 g/kg s.cut) tive metabolism of glucose for their energy lead to profound neurodegenerative changes requirements, and are susceptible to damage in retinal neurones of albino mice. These under conditions of ischaemia or hypoglycae­ changes were seen mainly in ganglion cells in mia. There has been an increased research adult animals, but in immature animals all ret­ effort in recent years devoted to the develop­ inal cells were affected. Olney and colleagues ment of pharmacological agents which might more than a decade
    [Show full text]
  • Supporting Information
    Supporting Information Ji et al. 10.1073/pnas.0904289106 SI Materials and Methods were then returned to serum-free Neurobasal media containing Reagents and Antibodies. N-terminal FLAG-D2 human cDNA glutathione (50 mM, 37 °C) for various times to allow internal- was a gift from Dr. Sibley’s laboratory, NINDS. Dysbindin-GFP ized receptors to recycle before neurons were cooled to 4 °C and was from GeneCopeia. Quinpirole, dopamine, haloperidol, a second round of glutathione treatment was applied to cleave SCH23390, NMDA receptor antagonist D-(Ϫ)-2-amino-5- phos- any newly appearing surface biotin. The disappearance of bio- phono-pentanoic acid (D-APV), and AMPA receptor antago- tinylated proteins as a function of time represents the rate of nist 6-Cyano-7-nitroquinoxaline-2, 3-dione (CNQX) were pur- recycling. Residual biotinylated receptors were isolated by chased from Sigma. EZ-Link sulfo-NHS-LC-biotin, sulfo-NHS- streptavidin precipitation and detected by immunoblotting. SS-Biotin, and Streptavidin agarose resins were from Pierce. Commercial antibodies were used against D2 (Abcam), amino- Receptor Recycling Experiments. Cells were incubated with M1 terminal D2 (Chemicon), D1 (Chemicon), TfR (Zymed labora- anti-FLAG mAb to selectively label FLAG-tagged receptors tories), LAMP1 (Developmental studies hybridoma bank), N- presented on the plasma membrane at the beginning of the Cad (Abcam), Tubulin (Abcam), M1, and M2 anti-FLAG experiment. Then cells were incubated at 37 °C for 60 min in the antibodies (Sigma). HRP-conjugated secondary antibodies were presence of 10 ␮M dopamine to drive internalization. At the end from Pierce. Alex-546 and Alex-488 conjugated secondary an- of this incubation, cells were quickly washed three times in PBS ϩ ϩ tibodies were from Molecular Probes.
    [Show full text]
  • Mapping Glutamatergic Drive in the Vertebrate Retina with a Channel-Permeant Organic Cation
    THE JOURNAL OF COMPARATIVE NEUROLOGY 407:47–64 ( 1999) Mapping Glutamatergic Drive in the Vertebrate Retina With a Channel-Permeant Organic Cation ROBERT E. MARC* J ohn Moran Eye Center, University of Utah School of Medicine, Salt Lake City, Utah 84132 ABSTRACT Patterns of neuronal excitation in complex populations can be mapped anatomically by activating ionotropic glutamate receptors in the presence of 1-amino-4-guanidobutane (AGB), a channel-permeant guanidinium analogue. Intracellular AGB signals were trapped with conventional glutaraldehyde fixation and were detected by probing registered serial thin sections with anti-AGB and anti-amino acid immunoglobulins, revealing both the accumu- lated AGB and the characteristic neurochemical signatures of individual cells. In isolated rabbit retina, both glutamate and the ionotropic glutamate receptor agonists ␣-amino-3- hydroxyl-5-methylisoxazole-4-propionic acid (AMPA), kainic acid (KA), and N-methyl-D- aspartic acid (NMDA) activated permeation of AGB into retinal neurons in dose-dependent and pharmacologically specific modes. Horizontal cells and bipolar cells were dominated by AMPA/KA receptor activation with little or no evidence of NMDA receptor involvement. Strong NMDA activation of AGB permeation was restricted to subsets of the amacrine and ganglion cell populations. Threshold agonist doses for the most responsive cell groups (AMPA, 300 nm; KA, 2 µM; NMDA, 63 µm; glutamate, 1 mM) were similar to values obtained from electrophysiological and neurotransmitter release measures. The threshold for activation of AGB permeation by exogenous glutamate was shifted to Ͻ 200 µM in the presence of the glutamate transporter antagonist dihydrokainate, indicating substantial spatial buffering of extracellular glutamate levels in vitro.
    [Show full text]
  • Evidence That Excitatory Amino Acid Receptors Within the Temporomandibular Joint Region Are Involved in the Reflex Activation of the Jaw Muscles
    The Journal of Neuroscience, October 1, 1998, 18(19):8056–8064 Evidence That Excitatory Amino Acid Receptors within the Temporomandibular Joint Region Are Involved in the Reflex Activation of the Jaw Muscles Brian E. Cairns, Barry J. Sessle, and James W. Hu Department of Oral Physiology, Faculty of Dentistry, The University of Toronto, Toronto, Ontario M5G 1G6, Canada We have previously shown that injection of the inflammatory comparable magnitude. Co-application of the NMDA receptor irritant and small-fiber excitant mustard oil (MO) into the tem- antagonist DL-2-amino-5-phosphonovalerate (0.5 mmol) signif- poromandibular joint (TMJ) region can reflexively induce a pro- icantly reduced the magnitude of the glutamate- and NMDA- longed increase in the activity of both digastric and masseter evoked ipsilateral jaw muscle responses without affecting re- muscles in rats. It is possible that peripheral excitatory amino sponses evoked by AMPA. In contrast, co-application of the acid (EAA) receptors play a role in this effect, because MO- non-NMDA receptor antagonist 6-cyano-7-nitroquinoxaline- evoked increases in jaw muscle activity are attenuated by 2,3-dione (1 nmol) significantly reduced the magnitude of the preapplication of the noncompetitive NMDA receptor antago- glutamate- and AMPA-evoked ipsilateral jaw muscle responses nist MK-801 into the TMJ region. In the present study the EAA without affecting responses evoked by NMDA. This evidence receptor agonists glutamate, NMDA, kainate, and AMPA were suggests that both NMDA and non-NMDA EAA receptor types applied locally to the TMJ region. Jaw muscle responses similar are located within the TMJ region and may contribute to jaw to those evoked by MO application to the TMJ region were muscle activity that can be reflexively evoked from the TMJ achieved with glutamate, NMDA, AMPA, and kainate.
    [Show full text]