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  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Journal of molecular medicine 52 (1974), S. 255-265 
    ISSN: 1432-1440
    Keywords: Tetanus toxin ; Antitoxin ; 125Iodine ; Spinal cord ; Nerves ; Tetanustoxin ; Antitoxin ; 125Jod ; Rückenmark ; Nerven
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Unsere Kenntnis der Pathogenese des Wundstarrkrampfes hat sich durch Anwendung neuer biochemischer und neurophysiologischer Techniken innerhalb der letzten Jahre erheblich erweitert. Radioaktiv markiertes Tetanustoxin wurde innerhalb verschiedener Nerven bis zu den Vorderhörnern des Rückenmarks verfolgt; dort wurde das Toxin z.T. noch auf cellulärer Ebene nachgewiesen. Die Verteilung des Toxins ist zeitabhängig und wird durch Antitoxin beeinflußt. Je weiter der Zeitpunkt der Vergiftung zurückliegt, desto geringer ist der Effekt des Antitoxins auf die Symptomatologie und die spinale Anreicherung des Toxins. Die neurale Wanderung des Toxins wird durch Erregung des toxinhaltigen Nerven gefördert. Neben den motorischen Anteilen sind auch rein sensibel-sensorische und vegetative Nerven zur Weiterleitung des Toxins imstande. Der generalisierte Tetanus kann als eine Sonderform des lokalen Tetanus betrachtet werden. Während bisher das klassische α-motorische System des Rückenmarks im Vordergrund der Untersuchungen stand, weisen neuere Arbeiten auf eine gleichzeitige, vielleicht sogar vorwiegende Enthemmung des γ-motorischen Systems hin. Außerdem werden vegetative Spinalreflexe enthemmt, was auch bei der Therapie bedacht werden sollte. Die Hemmwirkung des Tetanustoxins auf periphere Synapsen weist auf große Ähnlichkeiten mit Botulinumtoxin hin, obwohl die Symptome am vergifteten Tier so verschieden sind. Künftige Untersuchungen werden sich voraussichtlich mit der Wirkungsweise des Toxins auf molekularer und cellulärer Ebene befassen.
    Notes: Summary Due to the use of advanced biochemical and neurophysiological techniques, our knowledge of the pathogenesis of tetanus has considerably improved during the past years. Radio-labelled tetanus toxin has been traced within different nerves up to the anterior horn of the spinal cord where its localization down to the cellular level has been achieved. The distribution of labelled toxin depends on time and is influenced by antitoxin. The longer the duration of poisoning, the smaller the effect of antitoxin on the spinal enrichment of toxin and on the onset of toxic symptoms. The neural ascent of toxin into a spinal cord segment is enhanced by stimulation of the segmental nerves. Not only the motor nerves, but also sensory and vegetative nerves are able to serve as guide-rails for the toxin. The generalized tetanus has been understood as a special kind of local tetanus. For a long time, disinhibition of the alpha motor system was considered to be the characteristic action of tetanus toxin, but recent evidence is in favour of an additional disinhibition of the gamma motor system (perhaps even preceding the alpha disinhibition) and also of the sympathetic spinal reflexes. This finding should have therapeutic implications. The detection of inhibitory effects of tetanus toxin on peripheral cholinergic synapses points again to the close similarity between tetanus toxin and botulinum A toxin. The trends of future research will presumably lead to the elementary processes at the molecular and cellular level which are the basis of the clinical picture of tetanus.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Amsterdam : Elsevier
    Biochimica et Biophysica Acta (BBA)/Biomembranes 649 (1981), S. 481-486 
    ISSN: 0005-2736
    Keywords: (Erythrocyte) ; Hemolysis ; K^+loss ; Palytoxin
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Biology , Chemistry and Pharmacology , Medicine , Physics
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Amsterdam : Elsevier
    Biochimica et Biophysica Acta (BBA)/Biomembranes 688 (1982), S. 486-494 
    ISSN: 0005-2736
    Keywords: (Erythrocyte) ; Amphotericin B ; Palytoxin ; Permeability
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Biology , Chemistry and Pharmacology , Medicine , Physics
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Amsterdam : Elsevier
    Biochimica et Biophysica Acta (BBA)/Biomembranes 861 (1986), S. 165-176 
    ISSN: 0005-2736
    Keywords: (Erythrocyte membrane) ; (Na^+ + K^+)-ATPase ; Ligand binding ; Membrane permeability ; Ouabain ; Palytoxin
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Biology , Chemistry and Pharmacology , Medicine , Physics
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Naunyn-Schmiedeberg's archives of pharmacology 319 (1982), S. 101-107 
    ISSN: 1432-1912
    Keywords: Palytoxin ; Ouabain ; Erythrocytes ; Permeability ; ATPase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 1. Palytoxin in concentrations as low as 1 pM raises the potassium permeability of rat, human and sheep erythrocytes, and the sodium permeability of human erythrocytes. The release of potassium or sodium from human cells also occurs when extracellular sodium is replaced by choline. 2. Ouabain inhibits the release due to palytoxin of potassium ions from human, sheep and rat erythrocytes, and also the release of sodium ions from human cells. The glycoside effect is specific since a) it is already prominent with 5×10−8 M ouabain b) rat erythrocytes are less sensitive than human cells to ouabain c) potassium release due to amphotericin B or the Ca2+ ionophore A23187 is not influenced by ouabain and d) dog erythrocytes are resistant to palytoxin as well as to ouabain. 3. Palytoxin has no direct influence on the Na+, K+-ATPase. It inhibits the binding of [3H]ouabain to erythrocyte membranes within the same concentration range as unlabelled ouabain. It partially displaces bound [3H]ouabain, and partially inhibits the inactivation of erythrocyte ATPase by the glycoside. Depletion of ATP or of external Ca2+ renders the cells less sensitive to palytoxin. Nevertheless inhibition by ouabain can be still demonstrated with human cells whose ATP stores had been largely exhausted, and also in the absence of external Ca2+. 4. Palytoxin decreases the surface tension at the air-water interface. We assume that the formation of nonspecific pores by palytoxin is linked with its surface activity. Further experiments should demonstrate whether ouabain prevents the binding of palytoxin to erythrocytes (“receptor hypothesis”), or whether an ouabain-sensitive hydrolysis of trace amounts of ATP (“metabolic hypothesis”) promotes the palytoxin effect.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Springer
    Naunyn-Schmiedeberg's archives of pharmacology 323 (1983), S. 269-275 
    ISSN: 1432-1912
    Keywords: Palytoxin ; Tetraphenylphosphonium ; Depolarization ; Binding ; Borate ; Calcium
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Palytoxin in concentrations as low as 10−11 to 10−12 M promotes the outflow of the lipophilic [3H]-tetraphenylphosphonium ion from particulate brain cortex of guinea-pigs and rats, and from preloaded crude synaptosomes of rats, which indicates depolarization. The outflow is not influenced by tetrodotoxin or the calcium channel blocker nimodipin, or by substitution of choline for Na+ ions. It is increased by Ca2+ and by borate, the latter interacting with the toxin itself. To assess the fixation of palytoxin to biological membranes, a binding step was installed before the depolarization step. Palytoxin binds to membranes from rat brain, liver, kidney, human and dog erythrocytes, and to a lesser degree to liposomes made from rat brain or erythrocyte lipids. Binding is reversible. It is decreased by mild physical pretreatments of crude synaptosomes. Palytoxin binding is increased in the presence of micromolar concentrations of Ca2+ or borate. It is concluded that the potentiation of palytoxin actions by Ca2+ or borate is at least partially due to the promotion of its binding.
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Naunyn-Schmiedeberg's archives of pharmacology 323 (1983), S. 261-268 
    ISSN: 1432-1912
    Keywords: Palytoxin ; Erythrocyte ; Membrane ; Na+, K+-ATPase ; Calcium ; Ouabain
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Palytoxin increases the permeability of human erythrocytes and their resealed ghosts. To elucidate its mode of action the activation by ATP and Ca2+, the inhibition by ouabain, and the changes in permselectivity have been studied: 1. Depletion of cells from ATP considerably depresses their sensitivity towards palytoxin. Ouabain prevents the actions of the toxin, however, with different inhibition characteristics in normal and depleted cells. The concentration of palytoxin required to raise the K+ permeability is higher in ghosts than in erythrocytes. The sensitivity is restored by incorporating ATP which can be partially substituted by ADP and GTP but not by AMP, Pi, β-γ-methylene adenosine 5′-triphosphate or the chromium (III) complex of ATP. Ouabain inhibits the K+ release from resealed ghosts in the presence as well as absence of ATP. Ouabain also inhibits the palytoxin-triggered Na+ and choline efflux into Na+ medium, as well as the Na+, K+ and choline efflux into choline medium. Phosphate promotes the inhibitory action of ouabain. Incorporated vanadate or Mg2+ do not change the sensitivity of ghosts toward palytoxin. 2. External calcium down to 10 μM potentiates the action of palytoxin in ghosts resealed with or without ATP. In contrast to calcium ionophore A23187, palytoxin does not raise the influx of Ca2+. 3. Palytoxin triggers the formation of small pores in resealed ghosts. The efflux into Na+ medium decreases in the order K+≧Na+〉[3H]choline≫[14C]inositol〉[14C]sucrose, [3H]inulin≅0. Our data suggest that palytoxin, once bound to erythrocyte membranes, transforms the sodium pump, or its functional vicinity, into a pore allowing the passive transport of small ions. This process is assisted by ATP from inside whereas Ca2+ promotes from the outside the efficacy of palytoxin.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    Springer
    Naunyn-Schmiedeberg's archives of pharmacology 276 (1973), S. 361-373 
    ISSN: 1432-1912
    Keywords: Tetanus Toxin ; Iodine Labelling ; Spinal Cord ; Autoradiography ; Antitoxin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The in vivo interaction of 125I-labelled toxin with substructures of rat spinal cord has been studied. The rats were poisoned by i.v. injection about 40–50 h before sacrifice. 1. The labelled material accumulates in the grey substance, which is, on microdissection, about 6 times more active than the white. Autoradiography reveals that the toxin is particularly enriched in the ventrolateral part of the grey substance. 2. On ultracentrifugation of the homogenates, the label is preferentially fixed to the dense fractions known to contain the synaptosomes. However, a considerable part of the toxin is fixed to the lighter fractions too. 3. Upon gel filtration, the labelled material in SDS-homogenates from spinal cords poisoned in vivo is indistinguishable from toxin added to the homogenates already prepared. The same is true for the bulk of radioactivity when subjected to disc gel electrophoresis. 4. The labelled material is degraded by enzymes from spinal cord at pH 3.5, but not at pH 7.5. 5. The labelled material is relatively firmly bound to structures of spinal cord. The bonding is fairly resistant against washing, even in the presence of an excess of cold toxin, but it can be partially released by treatment with antitoxin. According to these findings, the labelled material is firmly but not irreversibly bound in vivo to discrete structures, corresponding preferentially to the synaptosomal fractions in the homogenates and the ventrolateral grey in the slices. No evidence has been found for its degradation in vivo. So far, the bulk of labelled material in the spinal cord is indistinguishable from tetanus toxin.
    Type of Medium: Electronic Resource
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  • 9
    Electronic Resource
    Electronic Resource
    Springer
    Naunyn-Schmiedeberg's archives of pharmacology 325 (1984), S. 85-87 
    ISSN: 1432-1912
    Keywords: Na+, K+-ATPase ; Palytoxin ; Ouabain ; Kidney ; Erythrocyte
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Hog kidney Na+, K+-ATPase, purified to the microsomal stage and activated with detergent, binds palytoxin, as shown by the nearly complete competition of the toxin with 3H-ouabain. The K i-values of palytoxin, but not of ouabain, depend on the protein concentration; this indicates additional binding sites for the toxin on kidney membranes. — Palytoxin inhibits the enzymatic activity of the detergent-activated preparation nearly completely (IC50 8·10−7 mol/l). Inhibition of ATPase activity and of ouabain binding are promoted by borate, a known activator of palytoxin. — Palytoxin also inhibits the Na+, K+-ATPase of erythrocyte ghosts in the same dose range. The data are discussed in context with the hypothesis (Chhatwal et al. 1983) that palytoxin raises the cellular permeability by altering the state of Na+, K+-ATPase or its environment.
    Type of Medium: Electronic Resource
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  • 10
    Electronic Resource
    Electronic Resource
    Springer
    Naunyn-Schmiedeberg's archives of pharmacology 276 (1973), S. 341-359 
    ISSN: 1432-1912
    Keywords: Tetanus Toxin ; Iodine Labelling ; Central Nervous System ; Receptors ; Antitoxin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 1. Lyophilized homogenate of rat brain binds 125I-labelled tetanus toxin better than does homogenate from spinal cord. This is in contrast to the in vivo behaviour of the toxin where it is bound only to spinal cord. Liver homogenate does not fix the toxin. 2. Autoradiography of preincubated slices from spinal cord shows that the radioactivity is evenly and nearly exclusively bound to gray matter. 3. Maximally 40% of the labelled material interacts with brain homogenate. The toxicity of the remaining supernatant is much more reduced than is its radio-activity. 125I-toxoid, prepared from labelled toxin by treatment with formol, is bound only very weakly. Thus we assume that our toxin preparation is already partially toxoided, and that binding to CNS matter bears some relevance to toxicity. 4. The fixation of the labelled toxin is reversible. The degree of reversibility depends on the conditions used. Binding can be nearly completely reversed or prevented by treatment with antitoxin, but not more than 50% of the binding is reversed by treatment with unlabelled toxin. Repeated washings also remove the bulk of the initially bound toxin. Thus binding sites with different affinities are to be assumed. 5. A complex between ganglioside and cerebroside binds the labelled toxin more firmly than does brain homogenate. No competition between unlabelled and labelled toxin has been observed for this solid phase. Antitoxin nearly completely prevents and largely reverses the fixation of labelled toxin. 6. On the basis of the selective, competitive reactivity of labelled and unlabelled tetanus toxin with brain matter, a radio receptor assay has been developed. It can be used for the measurement of tetanus toxin down to 5 ng. 7. Gradient centrifugation of sucrose homogenates preincubated with labelled toxin reveals one peak of radioactivity in the fractions where the synaptosomes are to be expected; the larger part of the toxin remains, however, unevenly distributed near the starting volume. 8. Desoxycholate solubilizes the complex between labelled toxin and brain matter with parallel dissolution of brain proteins. 9. Neither brain nor spinal cord homogenates degrade labelled toxin into TCA-soluble fragments at pH 7.5. Partial degradation occurs, however, at pH 3.5.
    Type of Medium: Electronic Resource
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