apamin

Summary

Summary: A highly neurotoxic polypeptide from the venom of the honey bee (Apis mellifera). It consists of 18 amino acids with two disulfide bridges and causes hyperexcitability resulting in convulsions and respiratory paralysis.

Top Publications

  1. ncbi Small-conductance, calcium-activated potassium channels from mammalian brain
    M Kohler
    Vollum Institute, L 474, Oregon Health Sciences University, 3181 Southwest Sam Jackson Road, Portland, OR 97201, USA J Maylie, Department of Obstetrics and Gyne
    Science 273:1709-14. 1996
  2. ncbi Ca(2+)-activated K+ channels: molecular determinants and function of the SK family
    Martin Stocker
    Wellcome Laboratory for Molecular Pharmacology, Department of Pharmacology, University College London, Gower Street, London WC1E 6BT, UK
    Nat Rev Neurosci 5:758-70. 2004
  3. ncbi Modulators of small- and intermediate-conductance calcium-activated potassium channels and their therapeutic indications
    Heike Wulff
    Department of Medical Pharmacology and Toxicology, University of California, Davis, CA 95616, USA
    Curr Med Chem 14:1437-57. 2007
  4. ncbi Effects of bee venom peptidergic components on rat pain-related behaviors and inflammation
    Y N Chen
    Institute for Functional Brain Disorders and Institute for Biomedical Sciences of Pain, Tangdu Hospital, Fourth Military Medical University, 1 Xinsi Road, Baqiao, Xi an 710038, PR China
    Neuroscience 138:631-40. 2006
  5. pmc Small-conductance calcium-activated potassium channel and recurrent ventricular fibrillation in failing rabbit ventricles
    Su Kiat Chua
    Krannert Institute of Cardiology, Division of Cardiology, Indiana University School of Medicine, Indianapolis, USA
    Circ Res 108:971-9. 2011
  6. pmc The Ca2+ activated SK3 channel is expressed in microglia in the rat striatum and contributes to microglia-mediated neurotoxicity in vitro
    Lyanne C Schlichter
    Genes and Development Division, Toronto Western Research Institute, University Health Network, Toronto, Ontario, M5T 2S8, Canada
    J Neuroinflammation 7:4. 2010
  7. pmc Characterization of an apamin-sensitive small-conductance Ca(2+)-activated K(+) channel in porcine coronary artery endothelium: relevance to EDHF
    M P Burnham
    School of Biological Sciences, University of Manchester, Manchester M13 9PT, UK
    Br J Pharmacol 135:1133-43. 2002
  8. ncbi Molecular identification and functional roles of a Ca(2+)-activated K+ channel in human and mouse hearts
    Yanfang Xu
    Department of Internal Medicine, University of California, Davis, California 95616, USA
    J Biol Chem 278:49085-94. 2003
  9. ncbi Apamin-sensitive calcium-activated potassium currents (SK) are activated by persistent calcium currents in rat motoneurons
    X Li
    University of Alberta, Edmonton, AB T6G 2S2, Canada
    J Neurophysiol 97:3314-30. 2007
  10. pmc Small conductance Ca2+-activated K+ channels formed by the expression of rat SK1 and SK2 genes in HEK 293 cells
    David C H Benton
    Department of Pharmacology, University College London, Gower Street, London WC1E 6BT, UK
    J Physiol 553:13-9. 2003

Detail Information

Publications214 found, 100 shown here

  1. ncbi Small-conductance, calcium-activated potassium channels from mammalian brain
    M Kohler
    Vollum Institute, L 474, Oregon Health Sciences University, 3181 Southwest Sam Jackson Road, Portland, OR 97201, USA J Maylie, Department of Obstetrics and Gyne
    Science 273:1709-14. 1996
    ..The channels that formed from the various subunits displayed differential sensitivity to apamin and tubocurare...
  2. ncbi Ca(2+)-activated K+ channels: molecular determinants and function of the SK family
    Martin Stocker
    Wellcome Laboratory for Molecular Pharmacology, Department of Pharmacology, University College London, Gower Street, London WC1E 6BT, UK
    Nat Rev Neurosci 5:758-70. 2004
    ....
  3. ncbi Modulators of small- and intermediate-conductance calcium-activated potassium channels and their therapeutic indications
    Heike Wulff
    Department of Medical Pharmacology and Toxicology, University of California, Davis, CA 95616, USA
    Curr Med Chem 14:1437-57. 2007
    ..1-KCa2.3 (a.k.a. SK1-SK3) and the intermediate-conductance channel KCa3.1 (a.k.a. IKCa1). The apamin-sensitive KCa2 channels contribute to the medium afterhyperpolarization and are crucial regulators of neuronal ..
  4. ncbi Effects of bee venom peptidergic components on rat pain-related behaviors and inflammation
    Y N Chen
    Institute for Functional Brain Disorders and Institute for Biomedical Sciences of Pain, Tangdu Hospital, Fourth Military Medical University, 1 Xinsi Road, Baqiao, Xi an 710038, PR China
    Neuroscience 138:631-40. 2006
    ..Among them, four active peptidergic components were characterized as apamin, mast-cell degranulating peptide (MCDP), phospholipase A(2) (PLA(2))-related peptide and melittin, respectively...
  5. pmc Small-conductance calcium-activated potassium channel and recurrent ventricular fibrillation in failing rabbit ventricles
    Su Kiat Chua
    Krannert Institute of Cardiology, Division of Cardiology, Indiana University School of Medicine, Indianapolis, USA
    Circ Res 108:971-9. 2011
    ..Fibrillation/defibrillation episodes in failing ventricles may be followed by action potential duration (APD) shortening and recurrent spontaneous ventricular fibrillation (SVF)...
  6. pmc The Ca2+ activated SK3 channel is expressed in microglia in the rat striatum and contributes to microglia-mediated neurotoxicity in vitro
    Lyanne C Schlichter
    Genes and Development Division, Toronto Western Research Institute, University Health Network, Toronto, Ontario, M5T 2S8, Canada
    J Neuroinflammation 7:4. 2010
    ..The purpose of this study was to examine expression of KCNN3/SK3 in CNS microglia in vivo and in vitro, and to use an established in vitro model to determine if this channel contributes to the neurotoxic capacity of activated microglia...
  7. pmc Characterization of an apamin-sensitive small-conductance Ca(2+)-activated K(+) channel in porcine coronary artery endothelium: relevance to EDHF
    M P Burnham
    School of Biological Sciences, University of Manchester, Manchester M13 9PT, UK
    Br J Pharmacol 135:1133-43. 2002
    1. The apamin-sensitive small-conductance Ca(2+)-activated K(+) channel (SK(Ca)) was characterized in porcine coronary arteries. 2...
  8. ncbi Molecular identification and functional roles of a Ca(2+)-activated K+ channel in human and mouse hearts
    Yanfang Xu
    Department of Internal Medicine, University of California, Davis, California 95616, USA
    J Biol Chem 278:49085-94. 2003
    ..Because of the marked differential expression of SK2 channels in the heart, specific ligands for Ca2+-activated K+ currents may offer a unique therapeutic opportunity to modify atrial cells without interfering with ventricular myocytes...
  9. ncbi Apamin-sensitive calcium-activated potassium currents (SK) are activated by persistent calcium currents in rat motoneurons
    X Li
    University of Alberta, Edmonton, AB T6G 2S2, Canada
    J Neurophysiol 97:3314-30. 2007
    ..Spikes/AHPs were evoked with current injection or ventral root stimulation. Application of the SK channel blocker apamin completely eliminated the mAHP, which was not significantly different in chronic and acute spinal rats...
  10. pmc Small conductance Ca2+-activated K+ channels formed by the expression of rat SK1 and SK2 genes in HEK 293 cells
    David C H Benton
    Department of Pharmacology, University College London, Gower Street, London WC1E 6BT, UK
    J Physiol 553:13-9. 2003
    ..Co-expression of rSK1 with rSK2 also changed the channel pharmacology. The sensitivity of SK current to block by apamin was reduced approximately 16-fold from an IC50 of 94 pM (for SK2 alone) to 1.4 nM (for SK2 and SK1 together)...
  11. pmc Bradykinin-induced, endothelium-dependent responses in porcine coronary arteries: involvement of potassium channel activation and epoxyeicosatrienoic acids
    Arthur H Weston
    Faculty of Life Sciences, University of Manchester, G38 Stopford Building, Manchester M13 9PT
    Br J Pharmacol 145:775-84. 2005
    ..of IK(Ca) and SK(Ca) channels using 10 microM TRAM-39 (2-(2-chlorophenyl)-2,2-diphenylacetonitrile) plus 100 nM apamin (leaving an iberiotoxin-sensitive component), whereas the response to substance P was abolished...
  12. ncbi Regional differences in distribution and functional expression of small-conductance Ca2+-activated K+ channels in rat brain
    Claudia A Sailer
    Institute for Biochemical Pharmacology, University Innsbruck, A 6020 Innsbruck, Austria
    J Neurosci 22:9698-707. 2002
    ..Whole-cell recording showed a sharp segregation of apamin-sensitive SK current within the hippocampal formation, in agreement with the SK2 distribution, suggesting that SK2 ..
  13. pmc Apamin-sensitive potassium current modulates action potential duration restitution and arrhythmogenesis of failing rabbit ventricles
    Yu Cheng Hsieh
    Department of Medicine, Division of Cardiology, Krannert Institute of Cardiology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
    Circ Arrhythm Electrophysiol 6:410-8. 2013
    b>Apamin-sensitive K currents (I(KAS)) are upregulated in heart failure. We hypothesize that apamin can flatten action potential duration restitution (APDR) curve and can reduce ventricular fibrillation duration in failing ventricles.
  14. pmc Heterogeneous upregulation of apamin-sensitive potassium currents in failing human ventricles
    Po Cheng Chang
    Division of Cardiology, Krannert Institute of Cardiology, Indianapolis, IN
    J Am Heart Assoc 2:e004713. 2013
    ..This study goal is to test the hypothesis that subtype 2 of the small-conductance Ca(2+) activated K(+) (SK2) channel and apamin-sensitive K(+) currents (IKAS) are upregulated in failing human ventricles.
  15. ncbi Differential distribution of three Ca(2+)-activated K(+) channel subunits, SK1, SK2, and SK3, in the adult rat central nervous system
    M Stocker
    Molekulare Biologie Neuronaler Signale, Max Planck Institut fur experimentelle Medizin, Gottingen, Germany
    Mol Cell Neurosci 15:476-93. 2000
    ..Our results reveal the functional role of SK channels with defined subunit compositions in some neurons and open the way to the identification of the molecular determinants of AHP currents in many brain regions...
  16. pmc Crucial role of a shared extracellular loop in apamin sensitivity and maintenance of pore shape of small-conductance calcium-activated potassium (SK) channels
    Kate L Weatherall
    School of Physiology and Pharmacology, University of Bristol, Bristol BS8 1TD, United Kingdom
    Proc Natl Acad Sci U S A 108:18494-9. 2011
    ..The archetypical blocker apamin displays some selectivity between SK channel subtypes, with SK2 being the most sensitive, followed by SK3 and then ..
  17. pmc SK2 and SK3 expression differentially affect firing frequency and precision in dopamine neurons
    J Deignan
    Vollum Institute, Oregon Health and Science University, Portland, OR 97239, USA
    Neuroscience 217:67-76. 2012
    ..of dopamine (DA) neurons in the substantia nigra (SN) pars compacta are strongly influenced by the activity of apamin-sensitive small conductance Ca(2+)-activated K(+) (SK) channels...
  18. ncbi Does small-conductance calcium-activated potassium channel contribute to cardiac repolarization?
    Norbert Nagy
    Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary
    J Mol Cell Cardiol 47:656-63. 2009
    ..A previous study reported a significant lengthening effect of apamin, a selective SK channel inhibitor, on the action potential duration in atrial and ventricular mouse cardiomyocytes ..
  19. ncbi Active K+ secretion through multiple KCa-type channels and regulation by IKCa channels in rat proximal colon
    William J Joiner
    Department of Internal Medicine, Yale University, 333 Cedar Street, P O Box 208019, New Haven, CT 06520, USA
    Am J Physiol Gastrointest Liver Physiol 285:G185-96. 2003
    ..In contrast, only partial inhibition was observed with the BK and SK channel inhibitors, iberiotoxin and apamin, respectively...
  20. ncbi Apamin-sensitive small conductance calcium-activated potassium channels, through their selective coupling to voltage-gated calcium channels, are critical determinants of the precision, pace, and pattern of action potential generation in rat subthalamic nu
    Nicholas E Hallworth
    University of Tennessee, Anatomy and Neurobiology, Memphis, Tennessee 38163, USA
    J Neurosci 23:7525-42. 2003
    ..from postnatal day 16 (P16)-P30 rats and held at 37 degrees C] and then treated with the SK KCa channel antagonist apamin or the SK KCa channel agonist 1-ethyl-2-benzimidazolinone or the Cav channel antagonists w-omega-conotoxin GVIA (..
  21. ncbi Evidence for involvement of both IKCa and SKCa channels in hyperpolarizing responses of the rat middle cerebral artery
    Alister J McNeish
    Department of Pharmacy and Pharmacology, University of Bath, Bath, UK
    Stroke 37:1277-82. 2006
    ....
  22. ncbi Apamin interacts with all subtypes of cloned small-conductance Ca2+-activated K+ channels
    M Grunnet
    Department of Medical Physiology, The Panum Institute, University of Copenhagen, Denmark
    Pflugers Arch 441:544-50. 2001
    The purpose of the present study was to examine how apamin interacts with the three cloned subtypes of small-conductance Ca2+-activated K+ channels (hSK1, rSK2 and rSK3)...
  23. pmc Accumulation of cytoplasmic calcium, but not apamin-sensitive afterhyperpolarization current, during high frequency firing in rat subthalamic nucleus cells
    Mark Teagarden
    Department of Biology, University of Texas at San Antonio, San Antonio, TX 78249, USA
    J Physiol 586:817-33. 2008
    ..One of these is an apamin-sensitive calcium-dependent potassium current (SK)...
  24. ncbi Apamin modulates electrophysiological characteristics of the pulmonary vein and the Sinoatrial Node
    Wei Ta Chen
    Division of Cardiovascular Medicine, Department of Internal Medicine, Wan Fang Hospital, Taipei Medical University, Taiwan
    Eur J Clin Invest 43:957-63. 2013
    ..Blocking SK channels prolongs action potential (AP) duration and attenuate electrical remodelling. The effects of SK blocking on the pulmonary vein (PV) and the sinoatrial node (SAN) remain unclear...
  25. pmc TEA- and apamin-resistant K(Ca) channels in guinea-pig myenteric neurons: slow AHP channels
    Fivos Vogalis
    Department of Anatomy and Cell Biology, University of Melbourne, Parkville, Victoria 3010, Australia
    J Physiol 538:421-33. 2002
    ..The ensemble averaged current had a similar time course to the current underlying the slow AHP. TEA- and apamin-resistant Ca(2+)-activated K(+) (K(Ca)) channels were present in inside-out patches excised from AH neurons...
  26. ncbi Apamin-sensitive K+ currents mediate arachidonic acid-induced relaxations of rabbit aorta
    Kathryn M Gauthier
    Department of Pharmacology and Toxicology, Medical College of Wisconsin, 8701 Watertown Plank Rd, Milwaukee, WI 53226, USA
    Hypertension 43:413-9. 2004
    ..001) or incubation with apamin (100 nmol/L, 26+/-7%; P<0.05) but not incubation with charybdotoxin (100 nmol/L, 41+/-5%)...
  27. pmc Apamin induces early afterdepolarizations and torsades de pointes ventricular arrhythmia from failing rabbit ventricles exhibiting secondary rises in intracellular calcium
    Po Cheng Chang
    Krannert Institute of Cardiology and the Division of Cardiology, Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana Second Section of Cardiology, Department of Medicine, Chang Gung Memorial Hospital and Chang Gung University School of Medicine, Taoyuan, Taiwan
    Heart Rhythm 10:1516-24. 2013
    A secondary rise of intracellular Ca(2+) (Cai) and an upregulation of apamin-sensitive K(+) current (I(KAS)) are characteristic findings of failing ventricular myocytes...
  28. ncbi Characterization of an apamin-sensitive potassium current in suprachiasmatic nucleus neurons
    K Teshima
    Center for Research on Occupational and Environmental Toxicology, L606, Oregon Health and Science University, 3181 Southwest Sam Jackson Park Road, Portland, OR 97239 3098, USA
    Neuroscience 120:65-73. 2003
    ..However, antagonists of small conductance Ca(2+)-activated K+ channels, apamin and d-tubocurarine, reduced the amplitude of the membrane afterhyperpolarization and inhibited the spike frequency ..
  29. pmc SKCa and IKCa Channels, myogenic tone, and vasodilator responses in middle cerebral arteries and parenchymal arterioles: effect of ischemia and reperfusion
    Marilyn J Cipolla
    Department of Neurology, University of Vermont, Burlington, VT 05405, USA
    Stroke 40:1451-7. 2009
    ....
  30. ncbi An apamin- and scyllatoxin-insensitive isoform of the human SK3 channel
    Oliver H Wittekindt
    Department of Applied Physiology, University of Ulm, Ulm, Germany
    Mol Pharmacol 65:788-801. 2004
    ..The most obvious distinguishing feature of this new isoform was that whereas hSK3 was blocked by apamin (Kd=0.8 nM), scyllatoxin (Kd=2.1 nM), and d-tubocurarine (Kd=33...
  31. ncbi SK2 encodes the apamin-sensitive Ca(2+)-activated K(+) channels in the human leukemic T cell line, Jurkat
    H Jager
    Department of Applied Physiology, University of Ulm, Albert Einstein Allee 11, D 89081, Ulm, Germany
    FEBS Lett 469:196-202. 2000
    ..The cloned and native channels are voltage-independent, Ca(2+)-activated, apamin-sensitive, show an equivalent voltage-dependent Ba(2+) block and possess a similar ion selectivity...
  32. pmc Postnatal expression of an apamin-sensitive k(ca) current in vestibular calyx terminals
    Frances L Meredith
    Department of Otolaryngology, University of Colorado at Anschutz Medical Campus, Aurora, CO 80045, USA
    J Membr Biol 244:81-91. 2011
    ..b>Apamin, a selective blocker of SK-type calcium-activated K(+) channels, was tested on calyx afferent terminals isolated ..
  33. ncbi The precursors of the bee venom constituents apamin and MCD peptide are encoded by two genes in tandem which share the same 3'-exon
    M Gmachl
    Institute of Molecular Biology, Austrian Academy of Sciences, Salzburg
    J Biol Chem 270:12704-8. 1995
    From a cDNA library prepared from venom glands of worker bees, clones encoding the precursors of apamin and MCD peptide have been isolated. The cDNAs are similar at the 5'-ends and identical in their 3'-regions...
  34. ncbi Calcium-dependent regulation of secretion in biliary epithelial cells: the role of apamin-sensitive SK channels
    Andrew P Feranchak
    University of Colorado Health Sciences Center, 4200 East 9th Avenue, Denver, Colorado 80262, USA
    Gastroenterology 127:903-13. 2004
    ..We have identified a Ca 2+ -activated K + channel (SK2) in biliary epithelium that is inhibited by apamin. The purpose of the present studies was to define the role of SK channels in Ca 2+ -dependent cholangiocyte ..
  35. ncbi Ion-channel modulators: more diversity than previously thought
    Sebastien Dilly
    Laboratory of Medicinal Chemistry and CIRM, University of Liege, 1 Avenue de l Hopital, 4000 Liege, Belgium
    Chembiochem 12:1808-12. 2011
    ..For instance, in K(Ca)2 (formerly SK) channels, the prototypic "blocker" apamin prevents conduction by an allosteric mechanism, while TRPV1 channels are prevented from closing by a tarantula ..
  36. ncbi Partial apamin sensitivity of human small conductance Ca2+-activated K+ channels stably expressed in Chinese hamster ovary cells
    T J Dale
    Ion Channel Biology Group, Systems Research, GlaxoSmithKline Research and Development, Medicines Research Centre, Gunnels Wood Road, Stevenage, Hertfordshire, SG1 2NY, UK
    Naunyn Schmiedebergs Arch Pharmacol 366:470-7. 2002
    The bee venom toxin apamin is an important drug tool for characterising small conductance Ca(2+)-activated K(+) channels (SK channels)...
  37. ncbi Characterisation of [(125)I]-apamin binding sites in rat brain membranes with HE293 cells transfected with SK channel subtypes
    K Finlayson
    Fujisawa Institute of Neuroscience, Department of Neuroscience, University of Edinburgh, Edinburgh EH8 9JZ, UK
    Neuropharmacology 41:341-50. 2001
    The pharmacology of [(125)I]-apamin binding sites was examined in rat cortical and hippocampal tissue and compared with membranes prepared from human embryonic kidney (HEK293) cells transfected with SK channel subtypes hSK1, rSK2 and rSK3...
  38. ncbi Tuning the excitability of midbrain dopamine neurons by modulating the Ca2+ sensitivity of SK channels
    Huifang Ji
    Department of Psychiatry, Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD 21228, USA
    Eur J Neurosci 29:1883-95. 2009
    ..adaptation and slowed spontaneous firing, effects attributable to an increase in the amplitude and duration of an apamin-sensitive afterhyperpolarization...
  39. ncbi Initial SAR studies on apamin-displacing 2-aminothiazole blockers of calcium-activated small conductance potassium channels
    Robert G Gentles
    Research and Development, Bristol Myers Squibb Co, 5 Research Parkway, Wallingford, CT 06492, USA
    Bioorg Med Chem Lett 18:5316-9. 2008
    An initial SAR study on a series of apamin-displacing 2-aminothiazole K(Ca)2 channel blockers is described...
  40. ncbi Apamin produces selective improvements of learning in rats
    O Deschaux
    Centre d Etudes du Bouchet, DGA, Vert le Petit, France
    Neurosci Lett 386:5-8. 2005
    The effect of apamin on learning was examined using two behavioral tasks where the animals were subjected to two trials separated by a 24h interval...
  41. ncbi Apamin induces plastic changes in hippocampal neurons in senile Sprague-Dawley rats
    Alejandra Romero-Curiel
    Laboratorio de Neuropsiquiatría, Instituto de Fisiologia, Universidad Autonoma de Puebla, CP 72570, Puebla, Puebla, Mexico
    Synapse 65:1062-72. 2011
    b>Apamin is a neurotoxin extracted from honey bee venom and is a selective blocker of small-conductance Ca²⁺-activated K⁺ channels (SK)...
  42. ncbi SK channels and NMDA receptors form a Ca2+-mediated feedback loop in dendritic spines
    Thu Jennifer Ngo-Anh
    Vollum Institute, Oregon Health and Science University, 3181 SW Sam Jackson Park Road, Portland, Oregon 97239, USA
    Nat Neurosci 8:642-9. 2005
    ..Thus, blocking SK channels facilitates the induction of long-term potentiation by enhancing NMDAR-dependent Ca(2+) signals within dendritic spines...
  43. ncbi Memory processing and apamin induce immediate early gene expression in mouse brain
    C Heurteaux
    Institut de Pharmacologie Moleculaire et Cellulaire, UPR 411 du CNRS, Sophia Antipolis, Valbonne, France
    Brain Res Mol Brain Res 18:17-22. 1993
    ..Injections of apamin, a bee venom neurotoxin that selectively blocks a class of Ca(2+)-activated K+ channels and improves learning and ..
  44. ncbi Apamin improves spatial navigation in medial septal-lesioned mice
    S Ikonen
    Department of Neuroscience and Neurology, University of Kuopio, Finland
    Eur J Pharmacol 347:13-21. 1998
    We investigated the effects of acute i.p. injections of the Ca2+-dependent K+ channel blocker, apamin, on water maze spatial navigation, Y-maze and passive avoidance behavior in intact and medial septal-lesioned mice. Apamin 0.02, 0...
  45. ncbi Binding and toxicity of apamin. Characterization of the active site
    C Labbe-Jullie
    Centre National de la Recherche Scientifique UA 1179, Faculte de Medecine Secteur Nord, Marseille, France
    Eur J Biochem 196:639-45. 1991
    The structural features of apamin, a natural octadecapeptide from bee venom, enabling binding to its receptor and the expression of toxicity in mice, have been delineated by studying the effects on binding and toxicity of chemical ..
  46. pmc The SK channel blocker apamin inhibits slow afterhyperpolarization currents in rat gonadotropin-releasing hormone neurones
    Masakatsu Kato
    Department of Physiology, Nippon Medical School, Sendagi 1, Bunkyo ku, Tokyo 113 8602, Japan
    J Physiol 574:431-42. 2006
    ..It is reported that the SK channel blocker apamin (10 pm-100 nm) blocks a medium afterhyperpolarization current but not an I(sAHP)...
  47. ncbi Control of electrical activity in central neurons by modulating the gating of small conductance Ca2+-activated K+ channels
    P Pedarzani
    , , Germany
    J Biol Chem 276:9762-9. 2001
    ....
  48. ncbi Differential expression of the small-conductance, calcium-activated potassium channel SK3 is critical for pacemaker control in dopaminergic midbrain neurons
    J Wolfart
    Medical Research Council, Anatomical Neuropharmacology Unit, Department of Pharmacology, Oxford University, Oxford OX1 3TH, United Kingdom
    J Neurosci 21:3443-56. 2001
    ..This provides a cellular framework to understand the functional consequences of altered SK3 expression, a candidate disease mechanism for schizophrenia...
  49. ncbi Enhancement of apamin-sensitive medium afterhyperpolarization current by anandamide and its role in excitability control in cultured hippocampal neurons
    Wei Wang
    Department of Physiology, Tongji Medical College, Huazhong University of Science and Technology, No 13, Hangkong Road, Wuhan, Hubei Province 430030, PR China
    Neuropharmacology 60:901-9. 2011
    ..Activation of apamin-sensitive, small conductance Ca(2+)-activated K(+) (SK) channels, probably SK2 and SK3 as the immunofluorescence ..
  50. ncbi Inhibition of apamin-sensitive calcium dependent potassium channels facilitate the induction of long-term potentiation in the CA1 region of rat hippocampus in vitro
    T Behnisch
    Leibniz Institute for Neurobiology, Project Group Neuropharmacology, Magdeburg, Germany
    Neurosci Lett 253:91-4. 1998
    Using field potential recording in the CA1-region of rat hippocampal slices we investigated the effect of apamin; a specific antagonist of small conductive calcium activated potassium channels on long-term potentiation (LTP)...
  51. pmc SK3 is an important component of K(+) channels mediating the afterhyperpolarization in cultured rat SCG neurones
    R Hosseini
    Department of Pharmacology, University College London, Gower Street, London WC1E 6BT, UK
    J Physiol 535:323-34. 2001
    1. Our aim was to identify the small-conductance Ca(2+)-activated K(+) channel(s) (SK) underlying the apamin-sensitive afterhyperpolarization (AHP) in rat superior cervical ganglion (SCG) neurones. 2...
  52. ncbi Apamin improves reference memory but not procedural memory in rats by blocking small conductance Ca(2+)-activated K(+) channels in an olfactory discrimination task
    C Fournier
    Laboratoire de Neurobiologie des Comportements, UMR 6562, , IBHOP, Traverse Susini, 13388 Marseille, Cedex 13, France
    Behav Brain Res 121:81-93. 2001
    b>Apamin blocks SK channels responsible for long-lasting hyperpolarization following the action potential. Using an olfactory associative task, the effect of an intracerebroventricular 0...
  53. ncbi Differential effects of two blockers of small conductance Ca2+-activated K+ channels, apamin and lei-Dab7, on learning and memory in rats
    Bedel Mpari
    Laboratoire de Neurobiologie Integrative et Adaptative, Neurobiologie des Processus Mnésiques, UMR 6149, CNRS Université de Provence, Marseille, France
    J Integr Neurosci 4:381-96. 2005
    ..e., apamin which recognizes SK2 and SK3 channels, and lei-Dab7 which binds SK2 channels only...
  54. pmc Small conductance Ca2+-activated K+ channel knock-out mice reveal the identity of calcium-dependent afterhyperpolarization currents
    Chris T Bond
    Vollum Institute, Oregon Health and Science University, Portland, Oregon 97239, USA
    J Neurosci 24:5301-6. 2004
    ..b>Apamin, which selectively suppresses a component of the mAHP, increases neuronal excitability and facilitates the ..
  55. ncbi Domain analysis of the calcium-activated potassium channel SK1 from rat brain. Functional expression and toxin sensitivity
    Dieter D'Hoedt
    Wellcome Laboratory for Molecular Pharmacology, Department of Pharmacology, University College London, Gower Street, London WC1E 6BT, U K
    J Biol Chem 279:12088-92. 2004
    ..In heterologous expression systems, SK2 and SK3 currents are blocked by the bee venom toxin apamin, just as well as the corresponding neuronal AHP currents...
  56. ncbi Effects of apamin on memory processing of hippocampal-lesioned mice
    S Ikonen
    Department of Neuroscience and Neurology, University of Kuopio, P O Box 1627, 70211, Kuopio, Finland
    Eur J Pharmacol 382:151-6. 1999
    We investigated the effects of acute i.p. injections of the Ca(2+)-dependent K(+) channel blocker, apamin, on water maze spatial navigation and radial arm maze performance in mice with partial hippocampal-lesions...
  57. ncbi Nitric oxide acts as a volume transmitter to modulate electrical properties of spontaneously firing neurons via apamin-sensitive potassium channels
    Liana Artinian
    Department of Biology, Georgia State University, Atlanta, Georgia 30302 4010, USA
    J Neurosci 30:1699-711. 2010
    ..Both effects of NO were mediated by inhibition of Ca-activated iberiotoxin- and apamin-sensitive K channels, but only inhibition of apamin-sensitive K channels fully mimicked all effects of NO on ..
  58. pmc Allosteric block of KCa2 channels by apamin
    Cedric Lamy
    Department of Physiology and Pharmacology, School of Medical Sciences, University of Bristol, Bristol BS8 1TD, United Kingdom
    J Biol Chem 285:27067-77. 2010
    ..They are characterized by their high sensitivity to the bee venom toxin apamin, but the mechanism of block is not understood. For example, apamin binds to both K(Ca)2.2 and K(Ca)2...
  59. ncbi Behavioral effects of apamin, a selective inhibitor of the SK(Ca)-channel, in mice and rats
    F J van der Staay
    CNS Research, Bayer AG, Wuppertal, Germany
    Neurosci Biobehav Rev 23:1087-110. 1999
    b>Apamin, a highly selective and potent peptide that blocks the SK(Ca)-channels has been suggested to be a cognition enhancer...
  60. pmc The pharmacology of hSK1 Ca2+-activated K+ channels expressed in mammalian cell lines
    M Shah
    Department of Pharmacology, University College London, Gower Street, London, WC1E 6BT
    Br J Pharmacol 129:627-30. 2000
    ..In these cell types, hSK1 forms an apamin-sensitive channel with an IC(50) for apamin of 8 nM in HEK293 cells and 12 nM in COS-7 cells...
  61. ncbi Small conductance Ca2+-activated K+ channels as targets of CNS drug development
    Thomas Blank
    Department of Molecular Neuroendocrinology, Max Planck Institute for Experimental Medicine, D 37075 Goettingen, Germany
    Curr Drug Targets CNS Neurol Disord 3:161-7. 2004
    ..Peptide toxins such as apamin and scyllatoxin, as well as organic compounds such as quaternary salts of bicuculline, dequalinium, UCL 1684 and ..
  62. ncbi Development of action potentials and apamin-sensitive after-potentials in mouse vestibular nucleus neurones
    M B Dutia
    Department of Physiology, Medical School, Edinburgh, UK
    Exp Brain Res 118:148-54. 1998
    ..Immature type B cells had somewhat narrower spontaneous spikes that were followed by a delayed, apamin-sensitive AHP...
  63. ncbi Characterization of the outer pore region of the apamin-sensitive Ca2+-activated K+ channel rSK2
    Heike Jäger
    Department of Applied Physiology, University of Ulm, Albert Einstein Allee 11, 89081 Ulm, Germany
    Toxicon 43:951-60. 2004
    ..Beside apamin, ScTX is a high affinity blocker of the SK2 channel, whereas CTX is unable to block current through SK2...
  64. pmc Evidence for an apamin-sensitive, but not purinergic, component in the nonadrenergic noncholinergic relaxation of the rat gastric fundus
    Diego Currò
    Institute of Pharmacology, School of Medicine, Catholic University of the Sacred Heart, L go F Vito, 1, I 00168 Rome, Italy
    Br J Pharmacol 143:785-93. 2004
    ..Pyridoxal-phosphate-6-azophenyl-2',4'-disulphonic acid (100 microM), apamin (0...
  65. ncbi P2Y1 receptors mediate apamin-sensitive and -insensitive inhibitory junction potentials in murine colonic circular smooth muscle
    Yong Zhang
    Gastrointestinal Diseases Research Unit, Queen s University, Kingston, Ontario, Canada
    J Pharmacol Exp Ther 333:602-11. 2010
    ..In most tissues this neurotransmission is apamin-sensitive, but recent studies in human colonic circular smooth muscle (CSM) suggest the presence of apamin-..
  66. ncbi Maurotoxin: a potent inhibitor of intermediate conductance Ca2+-activated potassium channels
    N A Castle
    Icagen Inc, Durham, North Carolina 27703, USA
    Mol Pharmacol 63:409-18. 2003
    ..Maurotoxin did inhibit (86)Rb efflux (IC(50), 45 nM) through, and (125)I-apamin binding (K(i), 10 nM) to SK channels in low ionic strength buffers (i.e...
  67. ncbi The noradrenergic inhibition of an apamin-sensitive, small-conductance Ca2+-activated K+ channel in hypothalamic gamma-aminobutyric acid neurons: pharmacology, estrogen sensitivity, and relevance to the control of the reproductive axis
    E J Wagner
    Department of Physiology and Pharmacology, Oregon Health Sciences University, Portland, Oregon 97201, USA
    J Pharmacol Exp Ther 299:21-30. 2001
    ..The corresponding I(AHP) was sensitive to antagonism by CdCl2 (200 microM), apamin (0.3-1 microM), and dequalinium (3 microM)...
  68. pmc A transiently expressed SK current sustains and modulates action potential activity in immature mouse inner hair cells
    Walter Marcotti
    School of Life Sciences, University of Sussex, Falmer, Brighton BN1 9QG, UK
    J Physiol 560:691-708. 2004
    ..3 Ca(2+) channels in its activation. On the basis of its high sensitivity to apamin (K(D) 360 pM) it was identified as a small-conductance Ca(2+)-activated K(+) current (SK), probably SK2...
  69. pmc An amino acid outside the pore region influences apamin sensitivity in small conductance Ca2+-activated K+ channels
    Andreas Nolting
    Laboratory of Molecular Pharmacology, Department of Pharmacology, University College London, Gower Street, London WC1E 6BT, United Kingdom
    J Biol Chem 282:3478-86. 2007
    ..The bee venom toxin apamin inhibits exclusively the three cloned SK channel subtypes (SK1, SK2, and SK3) with different affinity, highest for ..
  70. pmc Apamin inhibits NO-induced relaxation of the spontaneous contractile activity of the myometrium from non-pregnant women
    Beata Modzelewska
    Department of Biophysics, Medical University of Bialystok, ul, Mickiewicza 2A, 15 089 Bialystok, Poland
    Reprod Biol Endocrinol 1:8. 2003
    ..In order to assess whether apamin-sensitive K+ channels play a role in NO - induced relaxation of the human uterus, we have studied the effect of ..
  71. pmc Effects of intracellular stores and extracellular Ca(2+) on Ca(2+)-activated K(+) currents in mature mouse inner hair cells
    Walter Marcotti
    School of Life Sciences, University of Sussex, Falmer, Brighton BN1 9QG, UK
    J Physiol 557:613-33. 2004
    ..This current was still present during superfusion of either IbTx (60 nm) or apamin (300 nm) but was abolished in Cs(+)-based intracellular solution or during superfusion of 5 mm TEA, suggesting the ..
  72. ncbi Role of apamin-sensitive k(ca) channels for reticulospinal synaptic transmission to motoneuron and for the afterhyperpolarization
    Lorenzo Cangiano
    Department of Neuroscience, Nobel Institute for Neurophysiology, Karolinska Institute, 17177 Stockholm, Sweden
    J Neurophysiol 88:289-99. 2002
    ..injection of 1,2-bis-(2-aminophenoxy)-ethane-N,N,N',N'-tetraacetic acid (BAPTA; fast Ca(2+) chelator), and by apamin (selective toxin for K(Ca) channels of the SK subtype)...
  73. ncbi Apamin-sensitive, small-conductance, calcium-activated potassium channels mediate cholinergic inhibition of chick auditory hair cells
    W A Yuhas
    Department of Cell and Structural Biology, University of Colorado Health Sciences Center, Denver 80262, USA
    J Comp Physiol A 185:455-62. 1999
    ..The peptides apamin and charybdotoxin were used to distinguish the calcium-activated potassium channels involved in the acetylcholine ..
  74. ncbi K+ channels and the microglial respiratory burst
    R Khanna
    Division of Cellular and Molecular Biology, Toronto Western Research Institute, University Health Network, Toronto, Ontario, Canada
    Am J Physiol Cell Physiol 280:C796-806. 2001
    ..The respiratory burst was markedly inhibited by blockers of SK2 (apamin) and SK4 channels (clotrimazole and charybdotoxin), and to a lesser extent, by the potent Kv1.3 blocker agitoxin-2.
  75. ncbi Fast, but not slow, effects of olivocochlear activation are resistant to apamin
    N Yoshida
    Eaton-Peabody Laboratory, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, Massachusetts 02114, USA
    J Neurophysiol 85:84-8. 2001
    ..We measured in vivo effects of apamin, a blocker of small-conductance (SK) K(Ca) channels, and charybdotoxin, a blocker of large-conductance K(Ca) ..
  76. ncbi Bicuculline methiodide potentiates NMDA-dependent burst firing in rat dopamine neurons by blocking apamin-sensitive Ca2+-activated K+ currents
    S W Johnson
    Department of Physiology and Pharmacology, Oregon Health Sciences University, Portland 97201, USA
    Neurosci Lett 231:13-6. 1997
    b>Apamin, a bee venom toxin which blocks a Ca2+-dependent K+ current, potentiates N-methyl-D-aspartate (NMDA)-induced burst firing in dopamine neurons...
  77. ncbi An intermediate conductance K+ channel in the cell membrane of mouse intestinal smooth muscle
    F Vogalis
    Brockton West Roxbury VA Medical Center and Harvard Medical School, 1400 VFW Parkway, Boston, MA 02132, USA
    Biochim Biophys Acta 1371:309-16. 1998
    ..IK channels were blocked by 2-5 mM external TEA and were sensitive to both charybdotoxin (100 nM) and apamin (500 nM)...
  78. ncbi Protease-activated receptors mediate apamin-sensitive relaxation of mouse and guinea pig gastrointestinal smooth muscle
    T M Cocks
    Department of Pharmacology, University of Melbourne, Parkville, Victoria, Australia
    Gastroenterology 116:586-92. 1999
    ..The aim of this study was to determine if PAR-1 and PAR-2 mediate gastrointestinal smooth muscle relaxation and to clarify the underlying mechanisms...
  79. ncbi Chemical synthesis and structure-activity relationships of Ts kappa, a novel scorpion toxin acting on apamin-sensitive SK channel
    C Lecomte
    Biochemistry Laboratory, CNRS UMR 6560, Faculty of Medicine North, Marseille, France
    J Pept Res 54:369-76. 1999
    ..kappa, was indistinguishable from the natural toxin when tested in vitro in competition assay with radiolabelled apamin for binding to rat brain synaptosomes (IC50 = 3 nM)...
  80. ncbi Cholinergic synaptic inhibition of inner hair cells in the neonatal mammalian cochlea
    E Glowatzki
    The Center for Hearing Sciences, Department of Otolaryngology Head and Neck Surgery, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
    Science 288:2366-8. 2000
    ..The synaptic currents, as well as the inner hair cell's response to acetylcholine, are mediated by a nicotinic (alpha9-containing) receptor and result in the activation of small-conductance calcium-dependent potassium channels...
  81. ncbi Differential modulation of respiratory neuronal discharge patterns by GABA(A) receptor and apamin-sensitive K(+) channel antagonism
    V Tonkovic-Capin
    Zablocki Veterans Affairs Medical Center, Research Service, Wisconsin, Milwaukee 53295, USA
    J Neurophysiol 86:2363-73. 2001
    ..can also be produced by alterations in the amplitude of spike afterhyperpolarizations (AHPs) mediated by apamin-sensitive small-conductance Ca(2+)-activated K(+) (SK) channels...
  82. ncbi Tamapin, a venom peptide from the Indian red scorpion (Mesobuthus tamulus) that targets small conductance Ca2+-activated K+ channels and afterhyperpolarization currents in central neurons
    Paola Pedarzani
    Department of Physiology, University College London, London WC1E 6BT, United Kingdom
    J Biol Chem 277:46101-9. 2002
    ..This toxin distinguished between the SK channels underlying the apamin-sensitive I(AHP) and the Ca(2+)-activated K(+) channels mediating the slow I(AHP) (sI(AHP)) in hippocampal neurons...
  83. pmc Discrimination between subtypes of apamin-sensitive Ca(2+)-activated K+ channels by gallamine and a novel bis-quaternary quinolinium cyclophane, UCL 1530
    P M Dunn
    Department of Pharmacology, University College London
    Br J Pharmacol 117:35-42. 1996
    ..were tested for their ability to block actions mediated by the small conductance, apamin-sensitive Ca(2+)-activated K+ (SKCa) channels in rat cultured sympathetic neurones and guinea-pig isolated ..
  84. ncbi Solution structure of apamin determined by nuclear magnetic resonance and distance geometry
    J H Pease
    Department of Chemistry, Lawrence Berkeley Laboratory, University of California, Berkeley, California 94720
    Biochemistry 27:8491-8. 1988
    The solution structure of the bee venom neurotoxin apamin has been determined with a distance geometry program using distance constraints derived from NMR. Twenty embedded structures were generated and refined by using the program DSPACE...
  85. ncbi Emergence of intrinsic bursting in trigeminal sensory neurons parallels the acquisition of mastication in weanling rats
    Frédéric Brocard
    Universite de Montreal, Pavillon Paul Desmarais, C P 6128, Succursale Centre Ville, Montreal, Quebec H3C 3J7, Canada
    J Neurophysiol 96:2410-24. 2006
    ..Lowering extracellular [Ca(2+)] increased both I(NaP) and probability of bursting. We suggest that these mechanisms underlie burst generation in mastication and that similar processes may be found in other motor pattern generators...
  86. pmc Reduced hyperpolarization in endothelial cells of rabbit aortic valve following chronic nitroglycerine administration
    Nobuyoshi Kusama
    Department of Cellular and Molecular Pharmacology, Graduate School of Medical Sciences, Nagoya City University, Kawasumi 1, Nagoya, Aichi 467 8601, Japan
    Br J Pharmacol 146:487-97. 2005
    ..ACh (0.03-3 microM) induced a hyperpolarization through activations of both apamin- and charybdotoxin-sensitive Ca2+-activated K+ channels (K(Ca)) in rabbit AVECs...
  87. pmc Combination of Ca2+ -activated K+ channel blockers inhibits acetylcholine-evoked nitric oxide release in rat superior mesenteric artery
    E Stankevicius
    Department of Pharmacology, Faculty of Health Sciences, University of Aarhus, Aarhus C, Denmark
    Br J Pharmacol 149:560-72. 2006
    ..The present study investigated whether calcium-activated K+ channels are involved in acetylcholine-evoked nitric oxide (NO) release and relaxation...
  88. ncbi SK channel regulation of dendritic excitability and dendrodendritic inhibition in the olfactory bulb
    Brady J Maher
    Vollum Institute, Oregon Health and Science University, Portland, 97239, USA
    J Neurophysiol 94:3743-50. 2005
    ..brain slices from PND 14-21 mice, long step depolarizations (100 ms) in the mitral cell soma evoked a cadmium- and apamin-sensitive outward SK current lasting several hundred milliseconds...
  89. ncbi Small-conductance calcium-activated K+ channels are expressed in pancreatic islets and regulate glucose responses
    Natalia A Tamarina
    Department of Medicine, University of Chicago, Chicago, Illinois, USA
    Diabetes 52:2000-6. 2003
    ..The SK/IK channel-blockers apamin, dequalinium, and charybdotoxin caused increases in average [Ca(2+)](i) levels and in frequency of [Ca(2+)](i) ..
  90. ncbi Ca2+-activated K+-current density is correlated with soma size in rat vestibular-afferent neurons in culture
    Agenor Limon
    Institute of Physiology, Autonomous University of Puebla, Mexico
    J Neurophysiol 94:3751-61. 2005
    ....
  91. ncbi Estrogen and the Ca2+-mobilizing agonist ATP evoke acute NO synthesis via distinct pathways in an individual human vascular endothelium-derived cell
    Jian zhong Sheng
    Smooth Muscle Research Group, Libin Cardiovascular Institute and Department of Pharmacology and Therapeutics, Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada T2N 4N1
    Am J Physiol Cell Physiol 294:C1531-41. 2008
    ..inhibited by the respective small-conductance and intermediate-conductance calcium- activated K+ channel blockers apamin and charybdotoxin...
  92. ncbi Acetylcholine and ATP hyperpolarize endothelium via activation of different types of Ca(2+)-activated K+ channels
    S M Marchenko
    A A Bogomolets Institute of Physiology, National Academy of Science of Ukraine, Kiev
    Bull Exp Biol Med 134:422-4. 2002
    ..It was hypothesized that ATP- and acetylcholine-activated Ca(2+)-signals are spatially separated and generated in plasma membrane regions with predominant localization of SK- and IR-channels, respectively...
  93. ncbi Effects of increased intracellular Cl- concentration on membrane responses to acetylcholine in the isolated endothelium of guinea pig mesenteric arteries
    Yoshimichi Yamamoto
    Laboratory of Physiology, Nagoya City University School of Nursing, Mizuho ku, Nagoya, 467 8601, Japan
    J Physiol Sci 57:31-41. 2007
    ..The K(+) current was blocked by a combination of charybdotoxin and apamin and appears to result from the opening of IK(Ca) and SK(Ca) channels...
  94. ncbi 1-Ethyl-2-benzimidazolinone (EBIO) suppresses epileptiform activity in in vitro hippocampus
    Julieta Garduño
    Instituto Cajal, CSIC, Av Dr Arce 37, 28002 Madrid, Spain
    Neuropharmacology 49:376-88. 2005
    ....
  95. ncbi EDHF-mediated rapid restoration of hypotensive response to acetylcholine after chronic, but not acute, nitric oxide synthase inhibition in rats
    Kaushik M Desai
    Department of Pharmacology, University of Saskatchewan, Saskatoon, Canada
    Eur J Pharmacol 546:120-6. 2006
    ..determined in anesthetized rats before and after acute intravenous infusion of either L-NAME or a combination of apamin plus charybdotoxin that would selectively inhibit EDHF...
  96. ncbi Pharmacological evidence for the activation of Ca2+-activated K+ channels by meloxicam in the formalin test
    Mario I Ortiz
    Área Académica de Medicina del Instituto de Ciencias de la Salud, Universidad Autonoma del Estado de Hidalgo, Pachuca, Hidalgo, Mexico
    Pharmacol Biochem Behav 81:725-31. 2005
    ..However, local peripheral pretreatment of the paw with charybdotoxin and apamin (large- and small-conductance Ca2+-activated K+ channel inhibitors, respectively), 4-aminopyridine and ..
  97. pmc Cellular target of voltage and calcium-dependent K(+) channel blockers involved in EDHF-mediated responses in rat superior mesenteric artery
    P Ghisdal
    Laboratoire de Pharmacologie, , UCL 5410, Avenue Hippocrate, 54 - B 1200 Bruxelles, Belgium
    Br J Pharmacol 134:1021-8. 2001
    ..01 - 3 microM) was abolished by a combination of charybdotoxin (ChTX, 0.1 microM) plus apamin (Apa, 0.1 microM) and was inhibited by 68+/-6% (n=6) by 4-aminopyridine (4-AP, 5 mM). 3. ACh(0...
  98. ncbi Ca2+-dependent K+ channels from rat olfactory cilia characterized in planar lipid bilayers
    Karen Castillo
    Department of Biology, Faculty of Sciences, University of Chile, PO Box 653, Santiago, Chile
    FEBS Lett 579:1675-82. 2005
    ..All four ciliary KCas were observed: The 16 pS channel, K0.5,Ca=40 microM and apamin-sensitive; the 30 and 50 pS channel, K0...
  99. ncbi Nitric oxide mediates abnormal responsiveness of thyroid arteries in methimazole-treated patients
    Joaquin Ortega
    Department of Surgery, Hospital Clínico Research Unit, University of Valencia, Spain
    Eur J Endocrinol 152:551-6. 2005
    ..We studied the intervention of nitric oxide (NO), prostacyclin and endothelium-derived hyperpolarizing factor (EDHF) in mediating responses to acetylcholine in thyroid arteries from euthyroid and methimazole-treated (MT) patients...
  100. ncbi Contribution of Ca2+-activated K+ channels to hyperpolarizing after-potentials and discharge pattern in rat supraoptic neurones
    W Greffrath
    Institute of Physiology and Pathophysiology, Gutenberg University, Mainz, Germany
    J Neuroendocrinol 16:577-88. 2004
    ..The sHAP and spike-frequency adaptation were blocked by cadmium, as well as by the SK channel antagonist apamin. The fHAP was attenuated by the BK channel antagonist iberiotoxin (IbTX), by the BK/IK channel antagonist ..
  101. ncbi A novel scorpion toxin blocking small conductance Ca2+ activated K+ channel
    Chen Qi Xu
    Institute of Neuroscience, Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China
    Toxicon 43:961-71. 2004
    ..BmSKTx1 selectively inhibited apamin-sensitive SK currents in RACC with Kd of 0.72 microM and Hill coefficient of 2.2...

Research Grants45

  1. Optimization of KCa2 Channel Activators as Neuroscience Tools and Potential Drugs
    Heike Wulff; Fiscal Year: 2012
    ..1-2.3 (= SK1-3) genes and are best known for underlying the apamin-sensitive medium afterhyperpolarization current (mAHP) in neurons...
  2. Endothelial Lipoxygenase Metabolites and Vascular Tone
    WILLIAM BRYSON CAMPBELL; Fiscal Year: 2013
    ..It relax arteries, in part, by activating apamin-sensitive, small conductance, calcium-activated potassium (SKCa) channels and hyperpolarizing smooth muscle cells (..
  3. SK channels: Roles and mechanisms for dendritic excitability and plasticity
    James G Maylie; Fiscal Year: 2012
    DESCRIPTION (provided by applicant): Apamin-sensitive small conductance Ca2+-activated K+ channels (SK channels) are implicated in the molecular and cellular mechanisms underlying learning and memory, and blocking SK channels in vivo ..
  4. EICOSANOIDS, VASCULAR TONE AND BLOOD PRESSURE
    WILLIAM BRYSON CAMPBELL; Fiscal Year: 2010
    ..relaxations and hyperpolarizations that are blocked by LO inhibitors, high extracellular K ([K]o) and apamin. Thus, the endothelium-dependent relaxations and hyperpolarizations to ACh and AA are mediated by a LO metabolite ..
  5. Memory modulation by SK channels
    ROBERT WILLIAM STACKMAN; Fiscal Year: 2013
    ..Our preliminary findings indicate that the SK channel blocker, apamin enhances memory, while the SK channel activator, 1-EBIO impairs memory...
  6. Molecular Mechanisms of Synaptic SK2 Channel Function
    MELISSA HERNANDEZ KELLEY; Fiscal Year: 2013
    DESCRIPTION (provided by applicant): Apamin-sensitive small conductance calcium activated potassium channels (SK channels) are widely expressed in the brain...
  7. Endothelial SK3 Channel Modulation of EDHF is Estrogen Regulated
    Mike T Lin; Fiscal Year: 2013
    ..In response to cholinergic stimulation (e.g. acetylcholine, ACh), a transient elevation of [Ca^*]j activates apamin-sensitive, voltage-independent Ca^*-activated K"^ channels, SKS channels, which hyperpolarize the endothelial ..
  8. Pregnancy/NO Induced Changes in UAE Ca2+Signaling
    Ian M Bird; Fiscal Year: 2013
    ..Consistent with this, UAEC show sensitivity to antagonists of KCa function (Apamin and Tram34) with a resulting reduction in Ca2+ signaling...
  9. SK CHANNELS IN HYPEREXCITABLE SKELETAL MUSCLE
    John Adelman; Fiscal Year: 2001
    ..The cellular hallmark of these conditions is the appearance of receptors for the peptide toxin apamin, a potent blocker of small conductance calcium-activated potassium (SK) channels...
  10. Afterhyperpolarization in dopamine neurons, H2O2 and KATP channels
    Marat Avshalumov; Fiscal Year: 2009
    ..to the regulation of the frequency and pattern of spontaneous and evoked discharges and is mediated in part by apamin-sensitive Ca2+-activated K+ channels...
  11. INFLUENCE OF ALPHA-HELICES ON THE FOLDING OF APAMIN
    Jeffrey Nelson; Fiscal Year: 1992
    ..b>Apamin, a small bee venom protein which forms an alpha-helix on the C-terminal end and contains two disulfide bonds, will ..
  12. PEPTIDE AND PROBE MODULATION OF AQUEOUS DYNAMICS
    Theodore Krupin; Fiscal Year: 1993
    ..The molecular probes amiloride (sodium transport inhibitor) and apamin (potassium transport inhibitor) will be investigated for their effect on intraocular pressure.
  13. STRATEGIES FOR DIRECTING DISULFIDE PAIRING IN PROTEINS
    Grayson Snyder; Fiscal Year: 1993
    ..Experiments will evaluate factors contributing to folding of apamin and endothelin, two proteins with homologous cysteine positions but different sets of disulfides...
  14. CLONING/CHARACTERIZATING A MYOTONIC DYSTROPHY LOCUS
    LAURA RANUM; Fiscal Year: 2004
    ..changes found in DM2 are part of a common pathway also affected in DM1; 5) to determine whether molecular changes affecting RNA splicing, CUG binding proteins, and apamin receptors are similar to those found in DM1.
  15. CNS DA NEURONS--CELLULAR BASIS OF PATTERNED ACTIVITY
    Paul Shepard; Fiscal Year: 2002
    ..In the second specific aim, current and voltage clamp techniques will be used to test the hypothesis that an apamin-insensitive Ca2+-dependent conductance: (1) contributes to the hyperpolarization that terminates the plateau phase ..
  16. Ion Channel Regulation of Excitability in Immature Brain
    Anne E Anderson; Fiscal Year: 2010
    ..For these studies we will focus on SK2 and the current that it underlies, the apamin-sensitive AHP...
  17. ETHANOL-NEUROTRANSMITTER INTERACTIONS IN BRAIN NEURONS
    Mark Brodie; Fiscal Year: 2007
    ..SK can be reduced by drugs like apamin or by depletion of intracellular calcium...
  18. SK channel modulation of hippocampal function
    Rebecca Hammond; Fiscal Year: 2004
    ..Blocking SK channels with apamin abolishes the ImAHP and enhances neuronal excitability...
  19. Altered Accumbens Signaling Following Ethanol Exposure
    FREDERIC WOODWARD HOPF; Fiscal Year: 2010
    ..Altered spike firing and dopamine signaling in the NAcb could significantly influence the behavioral contribution of the NAcb, and in this way facilitate the onset of relapse. ..
  20. OPIOID EFFECTS ON HYPOTHALAMIC NEURONAL EXCITABILITY
    Martin Kelly; Fiscal Year: 2002
    ....
  21. Spike After-Potentials of Oxytocin Cells in Lactation
    Ryoichi Teruyama; Fiscal Year: 2005
    ..The specific aims of the application are to determine 1) what specific component of spike after-potentials (AHPs and DAP) is altered during lactation; 2) whether the responsive component is responsive to changes in the gonadal steroids. ..
  22. NEOSTRIATAL CHOLINERGIC INTERNEURONS FIRING PATTERNS
    Charles Wilson; Fiscal Year: 2001
    ....
  23. NEURONAL ORGANIZATION OF BASAL GANGLIA
    Charles Wilson; Fiscal Year: 2003
    ..This latter will allow us to determine whether there is an actual mismatch between physiological and anatomical estimates of connectivity (i.e. non-functional synaptic connections). ..
  24. PHARMACOLOGICAL REGULATION OF DOPAMINE NEURONAL ACTIVITY
    Steven Johnson; Fiscal Year: 2003
    ....
  25. Small Molecule Kv1.3 Blockers as New Therapeutics for Multiple Sclerosis
    Heike Wulff; Fiscal Year: 2007
    ..Lay: In multiple sclerosis the immune system attacks proteins in the brain of afflicted patients. The aim of this study is to identify and test new drugs that can suppress the white blood cells that are invading the brain. ..
  26. SK Channel Openers as Therapeutics for Cerebellar Ataxia
    Heike Wulff; Fiscal Year: 2007
    ..Taken together these important proof-of-concept studies will help to determine whether SK channel openers constitute a new therapeutic approach to improve motor performance in dominant cerebellar ataxias. ..
  27. CRCNS: Phase resetting predicts synchronization in hybrid hippocampal circuits
    CARMEN CASTRO CANAVIER; Fiscal Year: 2010
    ..Bullock, M. Woodman), graduate and postgraduate levels. With respect to diversity, at least one of the principal trainees will be an underrepresented minority and one principal investigator is female. ..
  28. NERVE SPROUTING AND ELECTRICAL REMODELING
    Peng Sheng Chen; Fiscal Year: 2003
    ..These studies may lead to novel insights into the mechanisms of ventricular arrhythmogenesis after MI and may help develop new methods for arrhythmia control. ..
  29. Fibrillation and Defibrillation
    Peng Sheng Chen; Fiscal Year: 2010
    ..These studies will provide us new insights into the mechanisms of VF and defibrillation, and help test the hypothesis that inhibition of SOICR is a novel approach to arrhythmia control. ..
  30. REPERFUSION EFFECTS ON CEREBRAL ARTERY FUNCTION
    Marilyn Cipolla; Fiscal Year: 2003
    ..Therefore, Aim 3 will investigate the effects of two types of thrombolytic agents (tissue-type and urokinase) on cerebral artery function, including myogenic processes. ..
  31. Experimental approaches to understanding the ENS and its disorders
    James Galligan; Fiscal Year: 2006
    ..This will help the attendees develop a network of professional contacts who can help the young investigator in the career development process. [unreadable] [unreadable]..
  32. Regulation of Vascular Tone During Cirrhosis
    ETHAN CARTER; Fiscal Year: 2003
    ..This project will not only define the cellular basis for hepatopulmonary syndrome, but will also contribute to our understanding of how pulmonary vascular tone is controlled at the most basic level. ..
  33. SECRETORY FUNCTION OF PANCREATIC DUCT CELLS
    Toan Nguyen; Fiscal Year: 2003
    ..b) characterize the vectorial release of ATP release from PDEC (autocrine action) c) study the effect of mast cell degranulation, resulting in ATP release, on PDEC secretion (paracrine action). ..
  34. Local Circuit Properties Underlying Cortical Plasticity
    PETER HICKMOTT; Fiscal Year: 2004
    ..These data will provide specific evidence for possible roles for changes in excitation and inhibition during cortical reorganization, and possible anatomical and mechanistic correlates for the changes. ..
  35. Regulation of Pulmonary Vascular Tone During Cirrhosis
    CHRYSTELLE GARAT CARTER; Fiscal Year: 2004
    ..This project will not only define the cellular basis for hepatopulmonary syndrome, but will also contribute to our understanding of how pulmonary vascular tone is controlled at the most basic level. ..
  36. Mechanisms of uterine vascular adaptation in pregnancy
    Natalia Gokina; Fiscal Year: 2006
    ..abstract_text> ..
  37. AVIAN VASCULAR FUNCTION
    Hiroko Nishimura; Fiscal Year: 2007
    ..The proposed projects will be supported by five distinguished consultants. [unreadable] [unreadable]..
  38. FUNCTIONAL REGENERATION OF LOCOMOTOR COMMAND NEURONS
    ANDREW MCCLELLAN; Fiscal Year: 2005
    ..abstract_text> ..
  39. Firing Pattern in Midbrain Dopamine Neurons
    CARMEN CANAVIER; Fiscal Year: 2007
    ..abstract_text> ..
  40. PRESYNAPTIC MECHANISMS IN THE INTESTINE
    James Galligan; Fiscal Year: 2008
    ..It is also anticipated that these studies will identify new targets for drugs that can be used to treat GI motility disorders. ..
  41. Cerebral Arteriole Function during Hyperglycemic Stroke
    Marilyn Cipolla; Fiscal Year: 2009
    ....
  42. Endothelial Function in the Cerebral Circulation
    Frank Faraci; Fiscal Year: 2009
    ..These studies should provide new insight into mechanisms of cerebral vascular protection during hypertension. ..
  43. TRPM4 Channels in the Control of Cerebral Artery Tone
    Scott Earley; Fiscal Year: 2005
    ..It is anticipated that these studies will generate significant new information regarding the role of mechanosensitive cation channels in the regulation of VSM membrane potential and the regulation of cerebral blood flow. ..
  44. Forebrain-Cerebellar Interaction During Learning
    John Disterhoft; Fiscal Year: 2008
    ..The data gathered here will also be useful for understanding and treating deficits in learning and memory in young and aging persons. ..
  45. Regulation and actions of NO in the cardiac plexus
    JEAN HARDWICK; Fiscal Year: 2005
    ..In particular, it will provide important information concerning the regulation and of NO in the control of cardiac function. ..