Tetrodotoxin

Total Page:16

File Type:pdf, Size:1020Kb

Tetrodotoxin TETRODOTOXIN O HO H O O N OH H2N H N HO OH OH Presentation by Neil Vasan Baran Lab Group Seminar August 13, 2003 TTX: Background • Toxic venom component of puffer fish or fugu (Spheroides rubripes), a Japanese delicacy (1 fish = ~$400) • First isolated in 1909 and named after puffer fish order Tetraodontidae • Structure first elucidated in 1964 by Woodward (confirmed by Kishi in 1965) • First synthesis by Kishi, et. al. in 1972 • Toxicity attributed to selective blockage of Na+ channels of skeletal muscles • Lethal dose for adult human = .001 mg • Upon ingestion, one feels tingling and lightheadedness but is lucid; paralysis and death ensue within 6-24 hours • 70-100 deaths each year, mostly in rural Japan • No known antidote exists 1 TTX: Structure O HO H O O N OH H2N H N HO OH OH O O O HO H O H OH O N N O H N OH 2 N H2N H HO H N HO OH OH OH OH Equilibrium mixture among ortho ester, anhydride, and lactone forms TTX: Kishi Synthesis Synthesis of Cyclohexane chiral core O O O H H Me , SnCl4 Me MsCl Me MeCN, rt Et N Me 3 (83%) (quant.) N O Me O Me O OH N OH N Ms H O OH H H H O o Me Me H Me H2O, 100 C NaBH4 m-CPBA Beckmann MeOH camphorsulfonic acidHO (96%) (75%) (61%) NH NH H NH O O O Ac Ac Ac 2 TTX: Kishi Synthesis Towards Tetrodamine H H H H H O O H O H Me H Me H Me 1) Al OCHMe2 3 HO (90% in 2 steps) O MPV-reduction O 2) H NH O NH O(COCH3)2, pyr. O NH O O OAc Ac Ac (95% in 2 steps) Ac H H O H O H H CH2OAc 1. o-DCB, reflux H CH2OAc AcOH, rt (76% in 6 steps)EtO O 2. m-CPBA, K2CO3 O (70% from CH2Cl2 EtO diethyl ketal) EtO NH H O NH H OAc OAc Ac Ac TTX: Kishi Synthesis Towards Tetrodamine H H O H H O H mCPBA H CH2OAc CH2OAc KOAc, AcOH o O CH2Cl2, rt O O 90 C, 2h (quant.) (quant.) O O NH H NH H AcO OAc AcO OAc Ac Ac AcO H O 1) O(COCH ) , pyr. O H H 3 2 H H OH 2) pyrolysis, 300 oC, vacuum OAc OAc CH2OAc OAc CH2OAc (80% in 2 steps) AcHN H AcHN H O O (acetylated AcO AcO H H tetrodamine) O O 3 TTX: Kishi Synthesis Tetrodamine to Tetrodotoxin O O SEt O H H H H H H OAc OAc OAc BF3 Et2O AcN SEt SEt CH2OAc CH2OAc CH2OAc OAc OAc o OAc CH2Cl2 120 C, 12h C AcHN H H N H AcHN N H O (92%) 2 O O AcO AcO AcO H H H O O O (acetylated tetrodamine) (20% in 3 steps from tetrodamine) HO O O HO H H H H OAc OAc NH NH 2 OAc CH2OAc 2 OAc CH2OAc 1) NaIO , THF, 0 oC C OsO C 4 AcHN N H 4 AcHN N H TTX O o O 2) NH4OH, MeOH AcO THF, -20 C AcO H H (25% from mono- O O acetylguanidine) TTX: Isobe Synthesis Retrosynthesis 4 TTX: Isobe Synthesis Sonogashira Coupling and Claisen Rearrangement OH OTBS OTBS O Oi-Pr O Oi-Pr TMS O Oi-Pr (61% in 4 steps) Pd(OAc)2, OH OH OH Ph3P, CuI, OAc I Et N, PhH (available in 2 steps from O ) 3 (99%) AcO OAc TMS OAc OTBS OTBS OTBS O Oi-Pr O Oi-Pr O Oi-Pr OMe K2CO3 PPTS/THF o-DCB BzO O (50% in 6 steps) 5 150 oC (89%) Me O O (94%) OTBDPS TMS TMS TTX: Isobe Synthesis Cyclohexenone and Exoolefin Synthesis 1) TBS-OTf OTBS 1) TBAF H2SO4 H O OMe Et N, lutidine O OMe THF H O MeOH O 3 2 5 and then 2) TBS-Cl BzO 2) Cl3CCOCl HgO (cat.) imid., DMF TBDPSO OH O DMAP, pyr. (82%) OBz O OTBS (74% in 4 steps) OTBDPS OTBS OH 1) NaBH4, O MeOH, rt O OMe O OH O OH 2) Me2C(OMe)2, BzO BzO CSA, acetone BzO 3) PPTS, MeOH (67% in 6 steps) O OBOM (93% in 3 steps) OBOM OTBDPS OTBDPS OTBDPS 5 TTX: Isobe Synthesis Previous Overman Rearrangement Problem with Overman Rearrangement TTX: Isobe Synthesis Installation of Nitrogen Functionality: Conjugate Carbamate Addition O 1) DIBAL-H O O O OH 2) TEMPO, NCS O 1) Cl3CCONCO O O COOMe COOMe 3) NaClO2, NaH2PO4, CH2Cl2 BzO HO O Me2C=CHMe-H2O 2) Et3N, MeOH H2N 4) TMS-CHN2 (99% in 2 steps) OBOM (78% in 4 steps) OBOM OBOM OTBDPS OTBDPS OTBDPS O O O O 1) t-BuOK, THF 1) Boc O, Et N O 2 3 Boc 2) LiBH , THF O NH OMMTr DMAP, THF 4 HO NH OMMTr 3) MMTrCl, pyr. 2) LiOH, MeOH (88% in 3 steps) (CH2Cl)2-H2O OBOM OBOM (84% in 2 steps) OTBDPS OTBDPS 6 TTX: Isobe Synthesis Construction of Lactone Bicycle O O Boc HO NH OMMTr (70% in 7 steps) OBOM OTBDPS TTX: Isobe Synthesis Introduction of Guanidine HO O AcO OBz Me 1) TFA, MeOH H Me O OAc O O 2) CAN Me O Me O O O MeCN-H2O BocHN BocHN 3) HgCl O (96% in 4 steps) O 2 NHBoc OBz OBz Et N-DMF BOM Ac 3 OH OAc (53% in 3 steps) BocN SMe OBz OBz AcO AcO 1) NaIO4 BocHN HO O H O MeOH-H2O Boc O HO O N OH 2) TFA, MeOH N N N BocN O O (50% in 3 steps) H (90% in 2 steps) H OBz Ac OBz Ac OAc OAc OBz AcO Ac Me O Ac O N O N N O Ac Ac OBz OAc 7 TTX: Isobe Synthesis Deprotection and Final Conversion OBz O O AcO HO O Ac Me O H Me O H O Ac O Et3N O O N O N O N N MeOH-H2O H2N + H2N N O N O N O Ac (85%) H OH H OH Ac OBz H H OAc OH OH (TTX-anhydride) O HO H O O TFA-d/D2O N OH (-) TTX H2N H N HO OH OH (TTX-ortho ester) TTX: Du Bois Synthesis Retrosynthesis OH HO O O OH OH HO HO OH OH O O OH HO OH HN N OH OH OHC OH O H H OH H NH2 HO CO2H stereospecific C-H amination Me Me HO O O Me Me OH O O HO OH 2 2 OR N2 OR H OH OHC O O O O H Rh-catalyzed HO CO H C-H insertion 2 R1O O R1O O 8 TTX: Du Bois Synthesis Rh-carbene C-H insertion O Me BnO2C OH Me O Me Me OH O O O O O O CO2Bn O COOt-Bu (64% in 5 steps) H HO OH OTBS (53% in 4 steps) TBSO OH O N2 Me Me O Me Me O 1) H2 (1200 psi), Rh-C, 1) Rh2(tpacam)4, CCl4 O O OTBS CF3CO2H-MeOH 2) NH BH , CH Cl -MeOH O Me 3 3 2 2 2) p-TsOH, 2,2-DMP; (75% in 2 steps) then t-BuCOCl, pyr., THF O Me O O O (77% in 2 steps) H CO t-Bu t-BuO2C O O 2 TTX: Du Bois Synthesis Construction of Lactone Bicycle Me Me Me Me Me O O O Me O O O O O O Me Me Ph2Se2, PhIO2 O Me o Me (56% in 3 steps) Me 100 C, pyr., PhCl O O O O Me H H (70%) H Me2NOC Me NOC CO t-Bu CO t-Bu 2 O 2 2 CO2t-Bu Me Me O Me O Me O 1) t-BuCO H O HO 2 O Me o O Me PhCl, 200 C O (77% in 2 steps) O Me 2) NaOMe, THF-MeOH O Me H O H Me2N (78% in 2 steps) OCOt-Bu OH O 9 TTX: Du Bois Synthesis Rh-nitrene C-H insertion Me Me O O Me Me O Me OH Me O O O O O O O O O O Me H NH O H 2 (66% in 3 steps) O Me O O O O H Me Me Cl OH Me Me Rh2(tfacam)4, PhI(OAc)2, Me O Me O Me Me o O OH MgO, DCE, 50 C O O O O O O O (55% with 38% reactant) NH (59% in 4 steps) NHBoc O O O O Me Cl Me Me Me TTX: Du Bois Synthesis Guanidine Insertion and Final Steps Me O Me O Me O Me Me NBoc Me OH OH OH O O NHBoc O O o O O O H2O, 110 C O BocHN SMe O NHBoc NH N (95%) 2 HgCl , Et N, NHBoc O O 2 3 O O O MeCN-CH2Cl2 O Me Me (80%) Me Me Me Me OH OH H O-CF CO H O O O O 2 3 2 HO OH O OH 5 days O3, Me2S, (4:1 mixture) (-) TTX CH2Cl2-MeOH; HO OH OH HN HN (65% from then H2O-CF3CO2H N OH N OH H H after deprotection) (1:1 mixture) H2N H2N ([-] TTX-ortho ester) ([-] TTX-anhydride) 10 Comparisons and Contrasts Chemist KISHI ISOBE DU BOIS Date Sept. 1972 Jan.
Recommended publications
  • Tetrodotoxin
    Niharika Mandal et al. / Journal of Pharmacy Research 2012,5(7),3567-3570 Review Article Available online through ISSN: 0974-6943 http://jprsolutions.info Tetrodotoxin: An intriguing molecule Niharika Mandal*, Samanta Sekhar Khora, Kanagaraj Mohanapriya, and Soumya Jal School of Biosciences and Technology, VIT University, Vellore-632013 Tamil Nadu, India Received on:07-04-2012; Revised on: 12-05-2012; Accepted on:16-06-2012 ABSTRACT Tetrodotoxin (TTX) is one of the most potent neurotoxin of biological origin. It was first isolated from puffer fish and it has been discovered in various arrays of organism since then. Its origin is still unclear though some reports indicate towards microbial origin. TTX selectively blocks the sodium channel, inhibiting action potential thereby, leading to respiratory paralysis. TTX toxicity is mainly caused due to consumption of puffer fish. No Known antidote for TTX exists. Treatment is symptomatic. The present review is therefore, an effort to give an idea about the distribution, origin, structure, pharmacol- ogy, toxicity, symptoms, treatment, resistance and application of TTX. Key words: Tetrodotoxin, Neurotoxin, Puffer fish. INTRODUCTION One of the most intriguing biotoxins isolated and described in the twentieth cantly more toxic than TTX. Palytoxin and maitotoxin have potencies nearly century is the neurotoxin, Tetrodotoxin (TTX, CAS Number [4368-28-9]). 100 times that of TTX and Saxitoxin, and all four toxins are unusual in being A neurotoxin is a toxin that acts specifically on neurons usually by interact- non-proteins. Interestingly, there is also some evidence for a bacterial bio- ing with membrane proteins and ion channels mostly resulting in paralysis.
    [Show full text]
  • Suppression of Potassium Conductance by Droperidol Has
    Anesthesiology 2001; 94:280–9 © 2001 American Society of Anesthesiologists, Inc. Lippincott Williams & Wilkins, Inc. Suppression of Potassium Conductance by Droperidol Has Influence on Excitability of Spinal Sensory Neurons Andrea Olschewski, Dr.med.,* Gunter Hempelmann, Prof., Dr.med., Dr.h.c.,† Werner Vogel, Prof., Dr.rer.nat.,‡ Boris V. Safronov, P.D., Ph.D.§ Background: During spinal and epidural anesthesia with opi- Naϩ conductance.5–8 The sensitivity of different compo- oids, droperidol is added to prevent nausea and vomiting. The nents of Naϩ current to droperidol has further been mechanisms of its action on spinal sensory neurons are not studied in spinal dorsal horn neurons9 by means of the well understood. It was previously shown that droperidol se- 10,11 lectively blocks a fast component of the Na؉ current. The au- “entire soma isolation” (ESI) method. The ESI Downloaded from http://pubs.asahq.org/anesthesiology/article-pdf/94/2/280/403011/0000542-200102000-00018.pdf by guest on 25 September 2021 thors studied the action of droperidol on voltage-gated K؉ chan- method allowed a visual identification of the sensory nels and its effect on membrane excitability in spinal dorsal neurons within the spinal cord slice and further pharma- horn neurons of the rat. cologic study of ionic channels in their isolated somata Methods: Using a combination of the patch-clamp technique and the “entire soma isolation” method, the action of droperi- under conditions in which diffusion of the drug mole- -dol on fast-inactivating A-type and delayed-rectifier K؉ chan- cules is not impeded by the connective tissue surround nels was investigated.
    [Show full text]
  • Biological Toxins Fact Sheet
    Work with FACT SHEET Biological Toxins The University of Utah Institutional Biosafety Committee (IBC) reviews registrations for work with, possession of, use of, and transfer of acute biological toxins (mammalian LD50 <100 µg/kg body weight) or toxins that fall under the Federal Select Agent Guidelines, as well as the organisms, both natural and recombinant, which produce these toxins Toxins Requiring IBC Registration Laboratory Practices Guidelines for working with biological toxins can be found The following toxins require registration with the IBC. The list in Appendix I of the Biosafety in Microbiological and is not comprehensive. Any toxin with an LD50 greater than 100 µg/kg body weight, or on the select agent list requires Biomedical Laboratories registration. Principal investigators should confirm whether or (http://www.cdc.gov/biosafety/publications/bmbl5/i not the toxins they propose to work with require IBC ndex.htm). These are summarized below. registration by contacting the OEHS Biosafety Officer at [email protected] or 801-581-6590. Routine operations with dilute toxin solutions are Abrin conducted using Biosafety Level 2 (BSL2) practices and Aflatoxin these must be detailed in the IBC protocol and will be Bacillus anthracis edema factor verified during the inspection by OEHS staff prior to IBC Bacillus anthracis lethal toxin Botulinum neurotoxins approval. BSL2 Inspection checklists can be found here Brevetoxin (http://oehs.utah.edu/research-safety/biosafety/ Cholera toxin biosafety-laboratory-audits). All personnel working with Clostridium difficile toxin biological toxins or accessing a toxin laboratory must be Clostridium perfringens toxins Conotoxins trained in the theory and practice of the toxins to be used, Dendrotoxin (DTX) with special emphasis on the nature of the hazards Diacetoxyscirpenol (DAS) associated with laboratory operations and should be Diphtheria toxin familiar with the signs and symptoms of toxin exposure.
    [Show full text]
  • Animal Venom Derived Toxins Are Novel Analgesics for Treatment Of
    Short Communication iMedPub Journals 2018 www.imedpub.com Journal of Molecular Sciences Vol.2 No.1:6 Animal Venom Derived Toxins are Novel Upadhyay RK* Analgesics for Treatment of Arthritis Department of Zoology, DDU Gorakhpur University, Gorakhpur, UP, India Abstract *Corresponding authors: Ravi Kant Upadhyay Present review article explains use of animal venom derived toxins as analgesics of the treatment of chronic pain and inflammation occurs in arthritis. It is a [email protected] progressive degenerative joint disease that put major impact on joint function and quality of life. Patients face prolonged inappropriate inflammatory responses and bone erosion. Longer persistent chronic pain is a complex and debilitating Department of Zoology, DDU Gorakhpur condition associated with a large personal, mental, physical and socioeconomic University, Gorakhpur, UttarPradesh, India. burden. However, for mitigation of inflammation and sever pain in joints synthetic analgesics are used to provide quick relief from pain but they impose many long Tel: 9838448495 term side effects. Venom toxins showed high affinity to voltage gated channels, and pain receptors. These are strong inhibitors of ion channels which enable them as potential therapeutic agents for the treatment of pain. Present article Citation: Upadhyay RK (2018) Animal Venom emphasizes development of a new class of analgesic agents in form of venom Derived Toxins are Novel Analgesics for derived toxins for the treatment of arthritis. Treatment of Arthritis. J Mol Sci. Vol.2 No.1:6 Keywords: Analgesics; Venom toxins; Ion channels; Channel inhibitors; Pain; Inflammation Received: February 04, 2018; Accepted: March 12, 2018; Published: March 19, 2018 Introduction such as the back, spine, and pelvis.
    [Show full text]
  • Saxitoxin and ,U-Conotoxins (Brain/Electric Organ/Heart/Tetrodotoxin) EDWARD MOCZYDLOWSKI*, BALDOMERO M
    Proc. Nati. Acad. Sci. USA Vol. 83, pp. 5321-5325, July 1986 Neurobiology Discrimination of muscle and neuronal Na-channel subtypes by binding competition between [3H]saxitoxin and ,u-conotoxins (brain/electric organ/heart/tetrodotoxin) EDWARD MOCZYDLOWSKI*, BALDOMERO M. OLIVERAt, WILLIAM R. GRAYt, AND GARY R. STRICHARTZt *Department of Physiology and Biophysics, University of Cincinnati College of Medicine, 231 Bethesda Avenue, Cincinnati, OH 45267-0576; tDepartment of Biology, University of Utah, Salt Lake City, UT 84112; and tAnesthesia Research Laboratories and the Department of Pharmacology, Harvard Medical School, Boston, MA 02115 Communicated by Norman Davidson, March 17, 1986 ABSTRACT The effect oftwo pL-conotoxin peptides on the 22 amino acids with amidated carboxyl termini (18). One of specific binding of [3H]saxitoxin was examined in isolated these toxins, GIIIA, has recently been shown to block muscle plasma membranes of various excitable tissues. pt-Conotoxins action potentials (18) and macroscopic Na current in a GITIA and GIHIB inhibit [3H]saxitoxin binding inlEkctrophorus voltage-clamped frog muscle fiber (19). At the single channel electric organ membranes with similar Kds of %50 x 10-9 M level, the kinetics of GIIIA block have been shown to in a manner consistent with direct competition for a common conform to a single-site binding model (Kd, 110 x 10-9 M at binding site. GITIA and GIIIB similarly compete with the 0 mV), from analysis of the statistics of discrete blocking majority (80-95%) of [3Hlsaxitoxin binding sites in rat skeletal events induced in batrachotoxin-activated Na channels from muscle with Kds of -25 and "140 x 10-9 M, respectively.
    [Show full text]
  • Evidence That Tetrodotoxin and Saxitoxin Act at a Metal Cation Binding Site in the Sodium Channels of Nerve Membrane (Solubilized Membrane/Receptors/Surface Charge) R
    Proc. Nat. Acad. Sci. USA 71 Vol. 71, No. 10, pp. 3936-3940, October 1974 Evidence That Tetrodotoxin and Saxitoxin Act at a Metal Cation Binding Site in the Sodium Channels of Nerve Membrane (solubilized membrane/receptors/surface charge) R. HENDERSON*, J. M. RITCHIE, AND G. R. STRICHARTZt Departments of Molecular Biophysics and Biochemistry, and of Pharmacology, Yale University School of Medicine, New Haven, Connecticut 06510 Communicated by Frederic M. Richards, June 17, 1974 ABSTRACT The effects of monovalent, divalent, and STX. These experiments suggest how the toxins exert their trivalent cations on the binding of tetrodotoxin and saxi- toxin to intact nerves and to a preparation of solubilized action, and provide a unifying explanation of how several nerve membranes have been examined. All eight divalent cations affect nerve membrane permeability. and trivalent cations tested, and the monovalent ions MATERIALS AND LiW, Tl+, and H+ appear to compete reversibly with the METHODS toxins for their binding site. The ability of lithium to Tritium-labeled TTX and STX were prepared and purified reduce toxin binding is paralleled by its ability to reduce (3, 5). Olfactory nerves from garfish, obtained from the Gulf tetrodotoxin-sensitive ion fluxes through the nerve mem- brane. We conclude that the toxins act at a metal cation Specimen Co., Florida, were dissected by the method of binding site in the sodium channel and suggest that this Easton (12). A detergent-solubilized extract of the nerves site is the principal coordination site for cations (normally was prepared by the method of Henderson and Wang (4). Na+ ions) as they pass through the membrane during an Binding experiments were also carried out on intact garfish action potential.
    [Show full text]
  • Alcohol Dependence and Withdrawal Impair Serotonergic Regulation Of
    Research Articles: Cellular/Molecular Alcohol dependence and withdrawal impair serotonergic regulation of GABA transmission in the rat central nucleus of the amygdala https://doi.org/10.1523/JNEUROSCI.0733-20.2020 Cite as: J. Neurosci 2020; 10.1523/JNEUROSCI.0733-20.2020 Received: 30 March 2020 Revised: 8 July 2020 Accepted: 14 July 2020 This Early Release article has been peer-reviewed and accepted, but has not been through the composition and copyediting processes. The final version may differ slightly in style or formatting and will contain links to any extended data. Alerts: Sign up at www.jneurosci.org/alerts to receive customized email alerts when the fully formatted version of this article is published. Copyright © 2020 the authors 1 Alcohol dependence and withdrawal impair serotonergic regulation of GABA 2 transmission in the rat central nucleus of the amygdala 3 Abbreviated title: Alcohol dependence impairs CeA regulation by 5-HT 4 Sophia Khom, Sarah A. Wolfe, Reesha R. Patel, Dean Kirson, David M. Hedges, Florence P. 5 Varodayan, Michal Bajo, and Marisa Roberto$ 6 The Scripps Research Institute, Department of Molecular Medicine, 10550 N. Torrey Pines 7 Road, La Jolla CA 92307 8 $To whom correspondence should be addressed: 9 Dr. Marisa Roberto 10 Department of Molecular Medicine 11 The Scripps Research Institute 12 10550 N. Torrey Pines Road, La Jolla, CA 92037 13 Tel: (858) 784-7262 Fax: (858) 784-7405 14 Email: [email protected] 15 16 Number of pages: 30 17 Number of figures: 7 18 Number of tables: 2 19 Number of words (Abstract): 250 20 Number of words (Introduction): 650 21 Number of words (Discussion): 1500 22 23 The authors declare no conflict of interest.
    [Show full text]
  • Dragon's Blood
    Available online at www.sciencedirect.com Journal of Ethnopharmacology 115 (2008) 361–380 Review Dragon’s blood: Botany, chemistry and therapeutic uses Deepika Gupta a, Bruce Bleakley b, Rajinder K. Gupta a,∗ a University School of Biotechnology, GGS Indraprastha University, K. Gate, Delhi 110006, India b Department of Biology & Microbiology, South Dakota State University, Brookings, South Dakota 57007, USA Received 25 May 2007; received in revised form 10 October 2007; accepted 11 October 2007 Available online 22 October 2007 Abstract Dragon’s blood is one of the renowned traditional medicines used in different cultures of world. It has got several therapeutic uses: haemostatic, antidiarrhetic, antiulcer, antimicrobial, antiviral, wound healing, antitumor, anti-inflammatory, antioxidant, etc. Besides these medicinal applica- tions, it is used as a coloring material, varnish and also has got applications in folk magic. These red saps and resins are derived from a number of disparate taxa. Despite its wide uses, little research has been done to know about its true source, quality control and clinical applications. In this review, we have tried to overview different sources of Dragon’s blood, its source wise chemical constituents and therapeutic uses. As well as, a little attempt has been done to review the techniques used for its quality control and safety. © 2007 Elsevier Ireland Ltd. All rights reserved. Keywords: Dragon’s blood; Croton; Dracaena; Daemonorops; Pterocarpus; Therapeutic uses Contents 1. Introduction ...........................................................................................................
    [Show full text]
  • Siteand Mechanism of Action of Resin Acids on Voltage-Gated Ion Channels
    Linköping University Medical Dissertation No. 1620 Site and Mechanism of Action of Resin Acids on Voltage-Gated Ion Channels Malin Silverå Ejneby Department of Clinical and Experimental Medicine Linköping University, Sweden Linköping 2018 © Malin Silverå Ejneby, 2018 Cover illustration: “The Charged Pine Tree Anchored to the Ground” was designed and painted by Daniel Silverå Ejneby. Printed in Sweden by LiU-Tryck, Linköping, Sweden, 2018 ISSN: 0345-0082 ISBN: 978-91-7685-318-4 TABLE OF CONTENTS ABSTRACT ............................................................................................................................... 1 POPULÄRVETENSKAPLIG SAMMANFATTNING ................................................................. 3 LIST OF ARTICLES .................................................................................................................. 5 INTRODUCTION ....................................................................................................................... 7 Ions underlie the electrical activity in the heart and brain .................................................. 7 A mathematical model for the nerve impulse - Hodgkin and Huxley ............................... 7 Cardiac action potentials – a great diversity of shapes ...................................................... 9 Voltage-gated ion channels ......................................................................................................... 9 General structure ....................................................................................................................
    [Show full text]
  • The Pharmacology of Voltage-Gated Sodium Channel Activators
    Accepted Manuscript The pharmacology of voltage-gated sodium channel activators Jennifer R. Deuis, Alexander Mueller, Mathilde R. Israel, Irina Vetter PII: S0028-3908(17)30155-7 DOI: 10.1016/j.neuropharm.2017.04.014 Reference: NP 6670 To appear in: Neuropharmacology Received Date: 13 February 2017 Revised Date: 28 March 2017 Accepted Date: 10 April 2017 Please cite this article as: Deuis, J.R., Mueller, A., Israel, M.R., Vetter, I., The pharmacology of voltage- gated sodium channel activators, Neuropharmacology (2017), doi: 10.1016/j.neuropharm.2017.04.014. This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. ACCEPTED MANUSCRIPT The Pharmacology of Voltage-gated Sodium channel Activators Jennifer R. Deuis 1,* , Alexander Mueller 1,* , Mathilde R. Israel 1, Irina Vetter 1,2,# 1 Centre for Pain Research, Institute for Molecular Bioscience, The University of Queensland, St Lucia, Qld 4072, Australia 2 School of Pharmacy, The University of Queensland, Woolloongabba, Qld 4102, Australia * Contributed equally # Corresponding author: [email protected] MANUSCRIPT ACCEPTED ACCEPTED MANUSCRIPT Abstract Toxins and venom components that target voltage-gated sodium (Na V) channels have evolved numerous times due to the importance of this class of ion channels in the normal physiological function of peripheral and central neurons as well as cardiac and skeletal muscle.
    [Show full text]
  • Title of the Dissertation
    ECOLOGICAL AND EVOLUTIONARY IMPLICATIONS FOR THE CONSERVATION OF PANAMANIAN GOLDEN FROGS by Corinne L. Richards A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy (Ecology and Evolutionary Biology) in the University of Michigan 2008 Doctoral Committee: Assistant Professor Laura Lacey Knowles, Co-Chair Professor Ronald A. Nussbaum, Co-Chair Associate Professor Mercedes Pascual Assistant Professor Johannes Foufopoulos Kevin C. Zippel, World Conservation Union Nature's first green is gold Her hardest hue to hold. Her early leaf's a flower; But only so an hour. Then leaf subsides to leaf. So Eden sank to grief, So dawn goes down to day. Nothing gold can stay. - Robert Frost © Corinne L. Richards All rights reserved 2008 To my Mom and Dad, who have always encouraged me following my dreams and to Geoff who is always game for an adventure. ii ACKNOWLEDGMENTS Many people helped bring this research to completion, both physically and intellectually, and I am grateful to them all. First, and foremost, I would like to thank my advisors and co-chairs, Lacey Knowles and Ron Nussbaum for their guidance, feedback, and constructive criticism. I am especially grateful to Lacey for her friendship and the time and effort she has invested in shaping me into an independent scientific investigator. I would also like to thank the remainder of my dissertation committee, Johannes Foufopoulos, Mercedes Pascual, and Kevin Zippel for their help and encouragement throughout. I am grateful to Amanda Zellmer, Tim Connallon, Elen Oneal, Huateng Huang, Bryan Carstens, Heather Adams, and Wendy Grus for their daily help, feedback, friendship and encouragement.
    [Show full text]
  • CSTX-1, a Toxin from the Venom of the Hunting Spider Cupiennius Salei, Is
    For submission to Neuropharmacology CSTX-1, a toxin from the venom of the hunting spider Cupiennius salei, is a selective blocker of L-type calcium channels in mammalian neurons *,1Helmut Kubista, 2Roberta A. Mafra, 3Youmie Chong, 3Graham M. Nicholson, 2Paulo S.L. Beirão, 2Jader S. Cruz, 4Stefan Boehm, 5Wolfgang Nentwig & 5Lucia Kuhn-Nentwig 1Center for Biomolecular Medicine and Pharmacology, Institute of Pharmacology, Medical University of Vienna, Waehringerstrasse 13a, A-1090, Vienna, Austria 2Department of Biochemistry and Immunology, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Av. Antonio Carlos 6627, 31270-901 Belo Horizonte, MG, Brazil 3Neurotoxin Research Group, Department of Medical & Molecular Biosciences, University of Technology, Sydney, City Campus, Broadway, Sydney, NSW 2007, Australia 4Institute of Experimental and Clinical Pharmacology, Medical University of Graz, Universitätsplatz 4, A-8010 Graz, Austria 5Zoological Institute, University of Bern, Baltzerstrasse 6, CH-3012 Bern, Switzerland *Author for correspondence: Telephone: ++43 1 4277 64146 Fax: ++ 43 1 4277 9641 E-mail: [email protected] H. Kubista et al. CSTX-1, a selective Cav channel blocker 2 Abstract The inhibitor cystine-knot motif identified in the structure of CSTX-1 from Cupiennius salei venom suggests that this toxin may act as a blocker of ion channels. Whole-cell patch clamp experiments performed on cockroach neurons revealed that CSTX-1 produced a slow voltage- independent block of both mid/low- (M-LVA) and high-voltage-activated (HVA) insect Cav channels. Since Cupiennius salei venom affects both insect as well as rodent species, we investigated whether Cav channel currents of rat neurons are also inhibited by CSTX-1.
    [Show full text]