Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Palytoxin  (7)
  • Acetylcholine  (3)
  • Antitoxin  (3)
  • 1
    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
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 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
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 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
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Naunyn-Schmiedeberg's archives of pharmacology 303 (1978), S. 133-138 
    ISSN: 1432-1912
    Keywords: Tetanus ; Botulism ; Acetylcholine ; Nerve tissue ; Cell cultures
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Primary nerve cell cultures derived from embryonic rat central nervous system form [3H]ACh from exogenous [3H]Ch, and release it upon potassium depolarization. Pretreatment of the cultures with botulinum-A toxin or tetanus toxin diminishes the cellular accumulation of [3H]ACh. Poisoning the cultures during the period of [3H]Ch uptake fails to lower [3H]ACh formation. Dependent on dosage, both toxins suppress the release of [3H]ACh upon potassium depolarization. Heat-denaturated toxins as well as tetanus toxin preincubated with tetanus antitoxin were without effect.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Naunyn-Schmiedeberg's archives of pharmacology 312 (1980), S. 255-263 
    ISSN: 1432-1912
    Keywords: Acetylcholine ; Tetanus toxin ; Botulinum toxin ; Myenteric plexus ; Transmitter release
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The effects of tetanus and botulinum A toxin were studied on the electrically stimulated myenteric plexus-ileum strip of the guinea pig. The concentrations used were in the range of 104–106 mouse LD50/ml. 1. Tetanus and botulinu, A toxin slowly decrease the amplitude of the contractile response to field stimulation in a dose-dependent manner without influencing the sensitivity to acetylcholine of the smooth muscle. 2. Development of paralysis is preceded by a latent period. Washing and antitoxin slow the paralytic process only when applied during the latent period. 3. The time course of development of paralysis depends on the activity of the strip. It can be slowed by rest, high [Mg2+], or low [Ca2+], and accelerated by raising the stimulation frequency. 4. Substances like 4-aminopyridine, sea anemone toxin II and scorpion toxin which prolong the membrane depolarization restore temporarily the contraction of partially paralysed muscle strips. 5. Poisoned preparations do not differ from controls in their total acetylcholine contents, whereas formation as well as release of [3H]-acetylcholine are decreased by either toxin. It is concluded that a) tetanus toxin and botulinum A toxin are qualitatively indistinguishable with respect to their actions on the postganglionic cholinergic neurons in the ileum, botulinum A toxin being 5 times more potent than tetanus toxin, b) the effects of the toxins at postganglionic cholinergic neurons in the ileum and at motor nerve endings are qualitatively similar, botulinum A toxin being about 500 times more potent than tetanus toxin at the latter preparation (see Habermann et al., 1980b, c) both toxins influence the turnover of acetylcholine but not its tissue concentration.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 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
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 7
    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
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 8
    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
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 9
    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
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 10
    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
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...