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. 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
  3. 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
  4. 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
  5. 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
  6. 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
  7. 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
  8. 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
  9. doi 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
  10. 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

Detail Information

Publications202 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. 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)...
  3. 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...
  4. 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...
  5. 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...
  6. 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...
  7. 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...
  8. 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...
  9. doi 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 ..
  10. 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...
  11. doi 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 ..
  12. 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...
  13. 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 ..
  14. 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 ..
  15. 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 ..
  16. 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...
  17. 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...
  18. 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...
  19. 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...
  20. 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 ..
  21. 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.
  22. 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)...
  23. 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...
  24. doi 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)...
  25. doi 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...
  26. 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 ..
  27. doi 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...
  28. 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
    ....
  29. 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
    ....
  30. 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...
  31. 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 ..
  32. doi 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-..
  33. 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...
  34. 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...
  35. 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...
  36. 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...
  37. 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...
  38. 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...
  39. 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 ..
  40. 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 ..
  41. 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...
  42. 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...
  43. 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...
  44. 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) ..
  45. 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)...
  46. 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...
  47. 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)...
  48. 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)...
  49. 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 ..
  50. 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)...
  51. 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.
  52. 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...
  53. 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 ..
  54. 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)...
  55. 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
    ....
  56. 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)...
  57. 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 ..
  58. 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...
  59. 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...
  60. 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...
  61. 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...
  62. 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)...
  63. 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...
  64. 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)...
  65. 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 ..
  66. 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 ..
  67. 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 (..
  68. 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...
  69. 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...
  70. 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...
  71. ncbi Analysis of L-NAME-dependent and -resistant responses to acetylcholine in the rat
    Paul A Dabisch
    Department of Pharmacology, Tulane University Health Sciences Center, New Orleans, LA 70112, USA
    Am J Physiol Heart Circ Physiol 294:H688-98. 2008
    ..The calcium-activated potassium (K(Ca)) antagonists charybdotoxin (ChTX) and apamin decreased the magnitude but not the duration of the hindlimb vasodilator response to ACh...
  72. 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...
  73. 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) ..
  74. 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
    ....
  75. pmc Ca2+-activated K+ channels in murine endothelial cells: block by intracellular calcium and magnesium
    Jonathan Ledoux
    Department of Pharmacology, College of Medicine, University of Vermont, Burlington 05405, USA
    J Gen Physiol 131:125-35. 2008
    ..However, blockers of IK(Ca) channels, charybdotoxin (ChTX), and of SK(Ca) channels, apamin (Ap), significantly reduced the whole-cell current...
  76. 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...
  77. 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...
  78. ncbi Calcium influx via L- and N-type calcium channels activates a transient large-conductance Ca2+-activated K+ current in mouse neocortical pyramidal neurons
    Xiaolu Sun
    Department of Pediatrics Section of Respiratory Medicine, Yale University School of Medicine, New Haven, Connecticut 06520, USA
    J Neurosci 23:3639-48. 2003
    ..component of the sustained currents were Ca2+ dependent and sensitive to charybdotoxin and iberiotoxin but not to apamin, suggesting that they were mediated by large-conductance Ca2+-activated K+ (BK) channels...
  79. ncbi Cloning and characterization of SK2 channel from chicken short hair cells
    T M Matthews
    Department of Biomedical Engineering, The Center for Hearing Sciences, Johns Hopkins University School of Medicine, 521 Traylor Building, 720 Rutland Ave, Baltimore, MD 21205 2195, USA
    J Comp Physiol A Neuroethol Sens Neural Behav Physiol 191:491-503. 2005
    ..reptiles and amphibians, acetylcholine released from efferent neurons inhibits hair cells via activation of an apamin-sensitive, calcium-dependent potassium current...
  80. ncbi Structure, function, and endothelium-derived hyperpolarizing factor in the caudal artery of the SHR and WKY rat
    Shaun L Sandow
    Division of Neuroscience, John Curtin School of Medical Research, Australian National University, Canberra, ACT, 0200, Australia
    Arterioscler Thromb Vasc Biol 23:822-8. 2003
    ..To quantify structural and functional characteristics of the caudal artery from spontaneously hypertensive (SHR) and normotensive Wistar Kyoto (WKY) rats with particular reference to endothelium-derived hyperpolarizing factor (EDHF)...
  81. 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 ..
  82. 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...
  83. ncbi Participation of intracellular Ca2+ stores in arteriolar conducted responses
    Yasuaki Yashiro
    First Department of Physiology, Shinshu University School of Medicine, Matsumoto 390 8621, Japan
    Am J Physiol Heart Circ Physiol 285:H65-73. 2003
    ..was mimicked by extraluminal application of tetraethylammonium or charybdotoxin but not by iberiotoxin, apamin, glibenclamide, barium, or 4-aminopirydine...
  84. 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...
  85. ncbi Negative inotropic effect of selective AT2 receptor stimulation and its modulation by the endocardial endothelium
    Paulo Castro-Chaves
    Department of Physiology, Faculty of Medicine, Alameda Prof Hernani Monteiro, 4200 319 Porto, Portugal
    Eur J Pharmacol 578:261-9. 2008
    ..activation was also performed in presence of NG-nitro-L-Arginine, indomethacin, proadifen, hydroxocobalamin, apamin plus charybdotoxin, Hoe-140 or PD-123,319, as well as, after endocardial endothelium removal...
  86. 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 ..
  87. 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...
  88. pmc The effects of Delta9-tetrahydrocannabinol in rat mesenteric vasculature, and its interactions with the endocannabinoid anandamide
    Saoirse E O'Sullivan
    School of Biomedical Sciences, University of Nottingham, Queen s Medical Centre, Nottingham NG7 2UH
    Br J Pharmacol 145:514-26. 2005
    ..to THC was inhibited by high K+ buffer, and by the following K+ channel inhibitors: charybdotoxin (100 nM), apamin (500 nM) and barium chloride (30 microM), but not by 4-aminopyridine, glibenclamide or tertiapin...
  89. 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...
  90. ncbi Somatostatinergic modulation of firing pattern and calcium-activated potassium currents in medium spiny neostriatal neurons
    E Galarraga
    Departamento de Biofisica, Instituto de Fisiologia Celular, Universidad Nacional Autonoma de Mexico, PO Box 70 253, Mexico City, DF 04510, Mexico
    Neuroscience 146:537-54. 2007
    ..Therefore, somatostatin actions appear to be the entrainment of projection neurons to the rhythms generated by some interneurons. Somatostatin is then capable of modifying the processing and output of the neostriatum...
  91. 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...
  92. ncbi Smooth muscle mediates circumferential conduction of hyperpolarization and relaxation to focal endothelial cell activation in large coronary arteries
    Stavros Selemidis
    Department of Pharmacology, Monash University, Wellington Road, Clayton, Victoria, 3800, Australia
    Naunyn Schmiedebergs Arch Pharmacol 375:85-94. 2007
    ..of endothelium-dependent hyperpolarization-the Ca2+ -activated potassium channel (KCa) channel inhibitors, apamin and charybdotoxin...
  93. 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
    ....
  94. ncbi Endothelium-derived hyperpolarization factor (EDHF) is up-regulated in a pig model of acute liver failure
    Sveinung Ekse
    Department of Anesthesiology and Intensive Care, University of Tromsø, University Hospital Northern Norway, Tromsø, Norway
    Scand J Gastroenterol 42:356-65. 2007
    ....
  95. ncbi Activity of endothelium-derived hyperpolarizing factor is augmented in monocrotaline-induced pulmonary hypertension of rat lungs
    Yoshiteru Morio
    Department of Respiratory Medicine, Juntendo University School of Medicine, Tokyo, Japan
    J Vasc Res 44:325-35. 2007
    ..Inhibition of EDHF with a combination of K(Ca) blockers, charybdotoxin (50 nM) plus apamin (50 nM), increased baseline vascular tone in MCT-induced hypertensive lungs...
  96. 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...
  97. ncbi A novel mechanism for the facilitation of theta-induced long-term potentiation by brain-derived neurotrophic factor
    Eniko A Kramar
    Department of Psychiatry and Human Behavior, University of California, Irvine, California 92612 1695, USA
    J Neurosci 24:5151-61. 2004
    ..b>Apamin, an antagonist of type 2 small-conductance Ca2+-activated potassium (SK2) channels, also reduced hippocampal AHPs ..
  98. ncbi Role of Ca2+-dependent potassium channels in in vitro anandamide-mediated mesenteric vasorelaxation in rats with biliary cirrhosis
    Ying Ying Yang
    Institute of Clinical Medicine, National Yang Ming University School of Medicine, Taipei, Taiwan
    Liver Int 27:1045-55. 2007
    ..to anandamide was suppressed by combinations of vascular Ca(2+)-dependent K(+) channel blockers (including apamin+charybdotoxin+iberiotoxin or apamin+TRAM-34+iberiotoxin) (TRAM-34, 1-[(2-chlorophenyl)diphenylmethyl]-1H-pyrazole)...
  99. ncbi Type 1 diabetes and hypercholesterolaemia reveal the contribution of endothelium-derived hyperpolarizing factor to endothelium-dependent relaxation of the rat aorta
    Wachirawadee Malakul
    Department of Physiology, Faculty of Pharmacy, Mahidol University, Thailand
    Clin Exp Pharmacol Physiol 35:192-200. 2008
    ..to inhibition by L-NNA or ODQ, but abolished by additional inhibition of K(Ca) channels with charybdotoxin plus apamin. 4...
  100. 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...
  101. 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...

Research Grants73

  1. INTRACELLULAR STUDY OF ETHANOL EFFECTS ON BRAIN NEURONS
    Mark Brodie; Fiscal Year: 2009
    ..Ethanol excitation is completely blocked by quinidine, but not by the other K channel blockers apamin, tetraethylammonium, barium or cesium...
  2. INTRACELLULAR STUDY OF ETHANOL EFFECTS ON BRAIN NEURONS
    Mark S Brodie; Fiscal Year: 2010
    ..Ethanol excitation is completely blocked by quinidine, but not by the other K channel blockers apamin, tetraethylammonium, barium or cesium...
  3. ENKEPHALINS--NEUROPHARMACOLOGY AND ABUSE POTENTIAL
    William Dewey; Fiscal Year: 1999
    ..demonstrated that acute morphine analgesia is antagonized by blockers of potassium channels such as glyburide and apamin. Consistent with this are in vitro observations that K+ channel antagonists prevent mu opioid-stimulated k+ efflux ..
  4. ENKEPHALINS--NEUROPHARMACOLOGY AND ABUSE POTENTIAL
    William Dewey; Fiscal Year: 2000
    ..demonstrated that acute morphine analgesia is antagonized by blockers of potassium channels such as glyburide and apamin. Consistent with this are in vitro observations that K+ channel antagonists prevent mu opioid-stimulated k+ efflux ..
  5. 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...
  6. SK CHANNELS IN HYPEREXCITABLE SKELETAL MUSCLE
    John Adelman; Fiscal Year: 1999
    ..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...
  7. SK CHANNELS IN HYPEREXCITABLE SKELETAL MUSCLE
    John Adelman; Fiscal Year: 2000
    ..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...
  8. SK CHANNELS IN HYPEREXCITABLE SKELETAL MUSCLE
    John Adelman; Fiscal Year: 2000
    ..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...
  9. 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...
  10. MOTONEURON HYPERACTIVITY AFTER SPINAL CORD INJURY
    JENNIFER CROCKETT; Fiscal Year: 1993
    ..In addition, changes in two ionic currents (a nifedipine-sensitive calcium current, (ICa2+), and an apamin-sensitive calcium-dependent potassium current, IK(Ca2+)), that are known to be responsible for plateau potentials ..
  11. Afterhyperpolarization in dopamine neurons, H2O2 and KATP channels
    Margaret Rice; 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...
  12. 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 ..
  13. EICOSANOIDS, VASCULAR TONE AND BLOOD PRESSURE
    William Campbell; Fiscal Year: 2009
    ..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 ..
  14. EICOSANOIDS, VASCULAR TONE AND BLOOD PRESSURE
    William Campbell; Fiscal Year: 2005
    ..endothelium-dependent relaxations and hyperpolarizations that are blocked by LO and CYP inhibitors, high [K]o and apamin. Thus, these relaxations and hyperpolarizations are mediated by a LO metabolite of AA...
  15. EICOSANOIDS, VASCULAR TONE AND BLOOD PRESSURE
    William Campbell; Fiscal Year: 2007
    ..endothelium-dependent relaxations and hyperpolarizations that are blocked by LO and CYP inhibitors, high [K]o and apamin. Thus, these relaxations and hyperpolarizations are mediated by a LO metabolite of AA...
  16. EICOSANOIDS, VASCULAR TONE AND BLOOD PRESSURE
    William Campbell; Fiscal Year: 2006
    ..endothelium-dependent relaxations and hyperpolarizations that are blocked by LO and CYP inhibitors, high [K]o and apamin. Thus, these relaxations and hyperpolarizations are mediated by a LO metabolite of AA...
  17. SK channels: Roles and mechanisms for dendritic excitability and plasticity
    James Maylie; Fiscal Year: 2009
    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 ..
  18. SK channels: Roles and mechanisms for dendritic excitability and plasticity
    James G Maylie; Fiscal Year: 2010
    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 ..
  19. INFLUENCE OF ALPHA-HELICES ON THE FOLDING OF APAMIN
    Jeffrey Nelson; Fiscal Year: 1990
    ..b>Apamin, a small bee venom protein which forms an alpha-helix on the C-terminal end and contains two disulfide bonds, will ..
  20. Novel Mechanisms in Enteric Inhibitory Neuretransmission
    VIOLETA MUTAFOVA YAMBOLIEVA; Fiscal Year: 2009
    ..is stored in synaptic vesicles, is released upon action potential firing, activates P2Y purinergic receptors and apamin-sensitive small conductance Ca2+-activated potassium (SK) channels on either interstitial cells of Cajal (ICC), ..
  21. 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.
  22. PEPTIDE AND PROBE MODULATION OF AQUEOUS DYNAMICS
    Theodore Krupin; Fiscal Year: 1991
    ..The molecular probes amiloride (sodium transport inhibitor) and apamin (potassium transport inhibitor) will be investigated for their effect on intraocular pressure.
  23. Investigations into the mouse olivocochlear system
    Douglas Vetter; Fiscal Year: 2007
    ..The mechanisms of action may include phosphorylation and inactivation of the sK2 calcium-activated apamin-sensitive potassium channel...
  24. ENDORPHINS, SLEEP AND MATURATION OF HYPOXIC RESPONSE
    Gabriel Haddad; Fiscal Year: 1990
    ..In addition, we will use pharmacologic manipulations (e.g., blockers such as TEA, apamin, Cobolt, TTX) ion substitutions (e.g...
  25. Investigations into the mouse olivocochlear system
    Douglas Vetter; Fiscal Year: 2006
    ..The mechanisms of action may include phosphorylation and inactivation of the sK2 calcium-activated apamin-sensitive potassium channel...
  26. Investigations into the mouse olivocochlear system
    Douglas Vetter; Fiscal Year: 2005
    ..The mechanisms of action may include phosphorylation and inactivation of the sK2 calcium-activated apamin-sensitive potassium channel...
  27. Investigations into the mouse olivocochlear system
    Douglas Vetter; Fiscal Year: 2004
    ..The mechanisms of action may include phosphorylation and inactivation of the sK2 calcium-activated apamin-sensitive potassium channel...
  28. STRATEGIES FOR DIRECTING DISULFIDE PAIRING IN PROTEINS
    Grayson Snyder; Fiscal Year: 1991
    ..Experiments will evaluate factors contributing to folding of apamin and endothelin, two proteins with homologous cysteine positions but different sets of disulfides...
  29. 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...
  30. Molecular physiology of SK2 channels in CA1 neurons
    John Adelman; Fiscal Year: 2007
    ..Blocking SK channels with apamin reduces the stimulus intensity that is required to induce NMDA receptor-dependent long-term potentiation at ..
  31. Molecular physiology of SK2 channels in CA1 neurons
    John Adelman; Fiscal Year: 2006
    ..Blocking SK channels with apamin reduces the stimulus intensity that is required to induce NMDA receptor-dependent long-term potentiation at ..
  32. DOPAMINE-OPIOD RECEPTOR INTERACTIONS IN BASAL FOREBRAIN
    Lynn Churchill; Fiscal Year: 1990
    ..The number of Ca+2-activated K+ channels will be determined by specific binding of the bee venom toxin, [125I]apamin. The number of guanine nucleotide binding (Go or Gi) proteins will be measured by [32P]ADP-ribosylation in the ..
  33. CLONING/CHARACTERIZATING A MYOTONIC DYSTROPHY LOCUS
    LAURA RANUM; Fiscal Year: 2002
    ..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.
  34. 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.
  35. CLONING/CHARACTERIZATING A MYOTONIC DYSTROPHY LOCUS
    LAURA RANUM; Fiscal Year: 2003
    ..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.
  36. CLONING/CHARACTERIZATING A MYOTONIC DYSTROPHY LOCUS
    LAURA RANUM; Fiscal Year: 2002
    ..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.
  37. CLONING/CHARACTERIZATING A MYOTONIC DYSTROPHY LOCUS
    LAURA RANUM; Fiscal Year: 2000
    ..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.
  38. SULFUR-SULFUR BRIDGING IN SOLID-PHASE PEPTIDE SYNTHESIS
    George Barany; Fiscal Year: 1990
    ..be applied to biologically active target molecules with one to three disulfides, including oxytocin, bactenecin, apamin, and neutrophil defensins...
  39. SMALL CONDUCTANCE CALCIUM ACTIVATED POTASSIUM CHANNELS
    John Adelman; Fiscal Year: 2001
    ..Subtypes of SK channels may be distinguished by different sensitivities to the bee venom peptide toxin apamin. Application of apamin to regions of the brain alters physiologically important processes, such as sleep patterns ..
  40. SMALL CONDUCTANCE CALCIUM ACTIVATED POTASSIUM CHANNELS
    John Adelman; Fiscal Year: 2000
    ..Subtypes of SK channels may be distinguished by different sensitivities to the bee venom peptide toxin apamin. Application of apamin to regions of the brain alters physiologically important processes, such as sleep patterns ..
  41. CENTRAL RHYTHMOGENESIS AND BEHAVIOR
    John Welsh; Fiscal Year: 1993
    ..Rhythmic activity of the olivo-cerebellar system will be manipulated by injecting the neurotoxin apamin into the inferior olive, in order to determine whether disrupting the rhythm of olivary activity disrupts muscle ..
  42. SMALL CONDUCTANCE CALCIUM ACTIVATED POTASSIUM CHANNELS
    John Adelman; Fiscal Year: 1999
    ..Subtypes of SK channels may be distinguished by different sensitivities to the bee venom peptide toxin apamin. Application of apamin to regions of the brain alters physiologically important processes, such as sleep patterns ..
  43. CNS DA NEURONS--CELLULAR BASIS OF PATTERNED ACTIVITY
    Paul Shepard; Fiscal Year: 2000
    ..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 ..
  44. CNS DA NEURONS--CELLULAR BASIS OF PATTERNED ACTIVITY
    Paul Shepard; Fiscal Year: 2001
    ..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 ..
  45. 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 ..
  46. CNS DA NEURONS--CELLULAR BASIS OF PATTERNED ACTIVITY
    Paul Shepard; Fiscal Year: 1999
    ..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 ..
  47. IONIC CURRENTS IN GASTROINTESTINAL MUSCULARIS MUCOSA
    HAMID AKBARALI; Fiscal Year: 1993
    ..will include the large conductance charybdotoxin-sensitive Ca2+-activated K+ channel, the smaller conductance apamin and [ATP]o-sensitive Ca2+-activated K+ channel and the glybencamide and [ATP]i-sensitive K+ channel...
  48. MOLECULAR PHYSIOLOGY OF SK CHANNELS IN CA1 NEURONS
    John Adelman; Fiscal Year: 2003
    ..In CA1 hippocampal pyramidal neurons (HPNs) the AHP has two kinetic components. The medium AHP is apamin-sensitive and is not affected by neurotransmitter-induced second messengers, while the slow AHP is insensitive to ..
  49. Memory modulation by SK channels
    ROBERT WILLIAM STACKMAN; Fiscal Year: 2010
    ..Our preliminary findings indicate that the SK channel blocker, apamin enhances memory, while the SK channel activator, 1-EBIO impairs memory...
  50. Memory modulation by SK channels
    Robert Stackman; Fiscal Year: 2009
    ..Our preliminary findings indicate that the SK channel blocker, apamin enhances memory, while the SK channel activator, 1-EBIO impairs memory...
  51. MOLECULAR PHYSIOLOGY OF SK CHANNELS IN CA1 NEURONS
    John Adelman; Fiscal Year: 2000
    ..In CA1 hippocampal pyramidal neurons (HPNs) the AHP has two kinetic components. The medium AHP is apamin-sensitive and is not affected by neurotransmitter-induced second messengers, while the slow AHP is insensitive to ..
  52. MOLECULAR PHYSIOLOGY OF SK CHANNELS IN CA1 NEURONS
    John Adelman; Fiscal Year: 2002
    ..In CA1 hippocampal pyramidal neurons (HPNs) the AHP has two kinetic components. The medium AHP is apamin-sensitive and is not affected by neurotransmitter-induced second messengers, while the slow AHP is insensitive to ..
  53. MOLECULAR PHYSIOLOGY OF SK CHANNELS IN CA1 NEURONS
    John Adelman; Fiscal Year: 2001
    ..In CA1 hippocampal pyramidal neurons (HPNs) the AHP has two kinetic components. The medium AHP is apamin-sensitive and is not affected by neurotransmitter-induced second messengers, while the slow AHP is insensitive to ..
  54. MOLECULAR PHYSIOLOGY OF SK CHANNELS IN CA1 NEURONS
    John Adelman; Fiscal Year: 2003
    ..In CA1 hippocampal pyramidal neurons (HPNs) the AHP has two kinetic components. The medium AHP is apamin-sensitive and is not affected by neurotransmitter-induced second messengers, while the slow AHP is insensitive to ..
  55. CLONING/CHARACTERIZATING A MYOTONIC DYSTROPHY LOCUS
    LAURA RANUM; Fiscal Year: 2001
    ..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.
  56. CALCIUM-ACTIVATED POTASSIUM CHANNELS IN SKELETAL MUSCLE
    Andrew Blatz; Fiscal Year: 1990
    ..goal of the research described in this proposal is to fully characterize the properties of small conductance, apamin- blocked Ca-activated K channels (SK channels) that are probably responsible for the sustained ..
  57. Molecular physiology of SK2 channels in CA1 neurons
    John Adelman; Fiscal Year: 2004
    ..Blocking SK channels with apamin reduces the stimulus intensity that is required to induce NMDA receptor-dependent long-term potentiation at ..
  58. Molecular physiology of SK2 channels in CA1 neurons
    John Adelman; Fiscal Year: 2005
    ..Blocking SK channels with apamin reduces the stimulus intensity that is required to induce NMDA receptor-dependent long-term potentiation at ..
  59. ETHANOL-NEUROTRANSMITTER INTERACTIONS IN BRAIN NEURONS
    Mark Brodie; Fiscal Year: 2006
    ..SK can be reduced by drugs like apamin or by depletion of intracellular calcium...
  60. 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...