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  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Naunyn-Schmiedeberg's archives of pharmacology 264 (1969), S. 172-186 
    ISSN: 1432-1912
    Keywords: Bovine Serum ; Kininogen ; Peptides ; Enzymes ; Structure Evaluation ; Rinderserum ; Kininogen ; Peptide ; Enzyme ; Struktur-aufklärung
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung 1. Rinderserum ergab beim Umsatz mit Pepsin niedermolekulare, kininliefernde Spaltstücke. Das durch Fällung, Verteilung, Gelfiltration und Jonenaustausch-Chromatographie vorgereinigte Hydrolysat ließ sich durch Papierchromatographie in 2 Fraktionen trennen, auf die sich die kininliefernde Gruppierung im Verhältnis 5∶1 verteilte. 2. Beide kininliefernde Fraktionen waren resistent gegen Carboxypeptidase B, was gegen eine C-terminale Position der Kininsequenz spricht. Sie waren aktivierbar durch Trypsin, Pankreaskallikrein und auch Carboxypeptidase A. Trypsin in höherer Konzentration entwickelte aus der Hauptfraktion (L) Bradykinin, während mit Pankreaskallikrein, Carboxypeptidase A und kleinen Trypsinmengen Met-Lys-Bradykinin entstand. Die „direkte“ Aktivität der Fraktionen am Meerschweinchenileum lag bei maximal 1–2% der „indirekten“. 3. Aus der chromatographisch langsameren Hauptfraktion (L) wurde hoch-spannungselektrophoretisch ein einheitliches Minimalsubstrat für Kininogenasen isoliert. In seiner Aminosäurenanalyse entsprach es dem aus gereinigtem Rinderserum-Kininogen isolierten Hauptpeptid PKFL; auch beim Edman-Abbau ergaben sich keine Unterschiede. 4. Die früher für gereinigtes Kininogen beschriebenen Sequenzen sind also auch für Gesamtserum repräsentativ. Hinweise auf andersartige Peptide, insbesondere auf solche mit der Kininsequenz in C-terminaler Position, ergaben sich nicht.
    Notes: Summary 1. Peptic treatment of bovine serum produced kinin yielding substances of low molecular weight. The hydrolyzate was purified by precipitation, partition, gel filtration and ion exchange chromatography. Subsequent paper chromatography revealed two fractions with a 5∶1 distribution of the kinin-yielding property. 2. Both kinin-yielding fractions were resistant to carboxypeptidase B, a finding which argues against a C-terminal position of the kinin sequence. They could be activated by trypsin, pancreatic kallikrein, and carboxypeptidase A. Higher concentrations of trypsin released bradykinin from the main fraction (L), whereas pancreatic kallikrein, carboxypeptidase A and low amounts of trypsin produced met-lysbradykinin. The “direct” activity of the fractions as measured on the guinea pig ileum was no more than 1–2% of the “indirect” activity. 3. A homogeneous minimal substrate was isolated from the chromatographically slower fraction L by high voltage electrophoresis. With respect to amino acid analysis and Edman degradation, it could not be distinguished from the peptide PKFL isolated from purified bovine kininogen. 4. Therefore, the sequences described previously in purified kininogen are also representative for whole serum. Evidence for different peptides, especially with the kinin sequence in C-terminal position, was not found.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Naunyn-Schmiedeberg's archives of pharmacology 280 (1973), S. 177-182 
    ISSN: 1432-1912
    Keywords: Tetanus Toxin ; Iodine Labeling ; Spinal Cord ; Histoautoradiography
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 125I-labeled tetanus toxin was injected intravenously and intramuscularly in rats. Specific localisation within the spinal cord was obtained by histoautoradiography. 1. In generalized tetanus grain density was maximal in the ventral grey matter of spinal cord. The grains were closely correlated to the motoneurons and their neuropil. Other areas showed background activity only. 2. In local tetanus the injected side was labeled selectively. High grain density regularly covered a distinct group of motoneurons and their neuropil. 3. There is some evidence for intracellular accumulation of the toxin since the maximum of grain density was found over the perikarya whilst the nucleus corresponded to a minimum. 4. Cells yielding high grain density were less intensively stained with toluidine blue than neighbouring unlabeled cells. It is concluded from these experiments that tetanus toxin develops its action within or around selected motoneurons and that it induces morphological alterations there.
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  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Naunyn-Schmiedeberg's archives of pharmacology 261 (1968), S. 252-270 
    ISSN: 1432-1912
    Keywords: Peptides ; Bee Venom ; Mast Cells ; Histamine ; Vascular Permeability ; Peptide ; Bienengift ; Mastzellen ; Histamin ; Gefäßpermeabilität
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Bienengift enthält neben dem universell zellschädigenden Melittin und der über Lysolecithinbildung wirksamen Phospholipase A ein drittes mastzelldegranulierendes (MCD-)Peptid. Seine Isolierung gelingt durch Kombination von Gelfiltration an Sephadex G 50 mit Ionenaustauschchromatographie an Carboxymethylcellulose und an Amberlite IRC-50. MCD-Peptid ist stark basisch (Isoelektrischer Punkt um pH 12). Sein minimales Molekulargewicht errechnet sich aus der Aminosäurenanalyse zu 2593. Das Peptid besteht aus 22 Aminosäuren, darunter 4 Halbcystinen. Es liegt in zwei verschiedenen Ladungszuständen vor, die sich bei Papierchromatographie, Papierelektrophorese und Aminosäurenanalyse einheitlich verhalten. MCD-Peptid ist an isolierten Rattenmastzellen (Histaminfreisetzung) und am Mesenterialhäutchen der Ratte (Mastzelldegranulation) etwa wirkungsgleich mit dem synthetischen Histaminliberator Compound 48/80. Melittin wirkt ca. 100- bzw. 10 mal schwächer und zeichnet sich überdies durch eine sehr flache Dosis-Wirkungsbeziehung bei der Histaminfreisetzung aus. Der Rattenblutdruck wird durch MCD-Peptid und Compound 48/80 in quantitativ und qualitativ vergleichbarer Weise gesenkt. Zwischen beiden Substanzen besteht kreuzweise Tachyphylaxie. Die Permeabilität der Hautgefäße der Ratte für zirkulierendes Evans-Blau steigt bei intracutaner Applikation von MCD-Peptid und Compound 48/80. Beide Substanzen sind hier stärker wirksam als Melittin. Die Hautgefäße des Kaninchens sprechen jedoch auf MCD-Peptid schwächer an als auf Melittin und Compound 48/80. Die Ratte reagiert auf i.v. Injektion von 0,5–10 mg/kg MCD-Peptid mit massiver Hyperämie der Acren. Eine kurzdauernde Spastik der Extremitäten weist auf einen zusätzlichen Angriff am motorischen System hin.
    Notes: Summary Bee venom contains three agents which can produce mast cell degranulation. Melittin is a universally acting surfactant; phospholipase A releases the mastocytolytic lysolecithin. A third mast cell degranulating (MCD) peptide has been isolated by gel filtration on Sephadex G 50, followed by chromatography on carboxymethylcellulose, and, finally, on Amberlite IRC-50. MCD-peptide is strongly basic (isoelectric point near pH 12). From the amino acid analysis, a minimum molecular weight of 2593 has been calculated. MCD-peptide consists of 22 amino acids, among them 4 halfcystine residues. It can be obtained in two fractions differing by charge, which appear homogeneous, however, on paper chromatography, paper electrophoresis, and amino acid analysis. When tested on isolated mast cells or on mesentery tissue of rats, MCD-peptide is equiactive with compound 48/80. On the other hand, melittin is 100 times less potent than compound 48/80 on the former tissue and 10 times less potent on the latter; moreover, the dose-response-relation of histamine release is flatter with melittin. MCD-peptide and compound 48/80 depress the blood pressure of rats in a quantitatively and qualitatively similar manner. Crossed tachyphylaxis has been demonstrated. Both substances increase the capillary permeability of rat skin upon intracutaneous injection. Melittin is less active on rat skin vessels. The skin capillaries of rabbits are, however, more sensitive to melittin and compound 48/80 than to MCD-peptide. MCD-peptide (0.5–10 mg/kg i.v.) produces in rats an extreme cyanosis of the acra. A short lasting spasm of the extremities points to an additional effect on the motor system of rats.
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  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Naunyn-Schmiedeberg's archives of pharmacology 267 (1970), S. 1-19 
    ISSN: 1432-1912
    Keywords: Tetanus Toxin-Labelled Protein ; Spinal Cord ; Pharmaco-kinetics ; Radioimmunassay ; Tetanustoxin ; Markierte Proteine ; Rückenmark ; Phar-makokinetik ; Radioimmunassay
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 1. The preparation and properties of125I-labelled tetanus toxin are described. 2. After intravenous injection there is a short phase when the labelled toxin is rapidly removed from the blood plasma. This initial period is followed by a slow second phase of decay which has a longer duration. The first phase in very pronounced in rabbits, but not in rats. Unlabelled toxin is removed equally fast from rabbit plasma, as has been revealed by measuring the immunological reactivity (so-called “junction test”) and toxicity. 3. Thirty minutes after i.v. administration torabbits about 2/3 of the radioactive label are found in the liver. The highest concentration is attained in the spleen. 24 hours later, the bulk of the label has been excreted in the urine and faeces, which indicates catabolism of the toxin. In therat, the concentration in the liver is much less prominent, and the excretion of the label is slower. In both species, the central nervous system does not accumulate more than just measurable quantities of the label, even if the animals are given large toxic doses. 4. After injection into the left gastrocnemius muscle of the rat, the labelled tetanus toxin is absorbed very slowly from the site of administration. It is taken up by the corresponding N. ischiadicus and the lumbar region of the spinal cord. The injection of toxin into the anterior leg leads to concentration of radioactivity in the cervical area of the medulla. The arrival of the label in the spinal cord coincides approximately with the appearance of local tetanus. Sectioning of the N. ischiadicus prevents the appearance of the local tetanus of the lower extremity. The enrichment of the toxin in the lumbar cord is prevented in operated, but not in sham-operated rats. 5. When the spinal cord was subdivided into four sectors, the label was found to be greatly concentrated in the ipsilateral ventral sector of the segment corresponding with the injected extremity. This indicates transport into the ventral roots. 6. 131I-labelled tetanus antitoxin also disappears very slowly from the rat gastrocnemius. In contrast to labelled tetanus toxin, however, it is not concentrated in the spinal cord.
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  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Naunyn-Schmiedeberg's archives of pharmacology 270 (1971), S. 1-9 
    ISSN: 1432-1912
    Keywords: Melittin ; Peptides ; Venoms ; Hemolysis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The hexacosapeptide melittin I, which is the main toxin of bee venom, has been synthesized by Lübke and Schröder. In addition, the following derivatives have been prepared which are probably also present in bee venom: melittin II (which differs by one serine), and N1-formylated melittin I and II. In pharmacological tests, the four synthetic peptides were qualitatively indistinguishable from natural melittin as prepared from bee venom. Theyhemolyzed rabbit erythrocytes with a flat dose-response curve. Melittin I exerted 92% of the activity of the natural substance, the three other peptides 90, 61 and 52% respectively.-Theirsurface activity was between 86 and 96% of that of the natural material.-In contrast to our previous reports, no differences were found in onset, degree and duration of the shortlastinghypotensive action in rabbits.-Toxicity (LD 50, mice) was about 4 mg/kg for natural melittin and for the synthetic melittins I and II. The toxicity of formylated melittins was not very different.-The five compounds caused a slow and prolongedcontraction of the guinea-pig ileum which led to tachyphylaxis. Peptide mapping confirmed the identity between the main compound of natural melittin and synthetic melittin I. The peptide pattern of synthetic melittin II is different and is further modified by the presence of the N-formyl group. Our findings leave no doubt as to the identity between the bulk of natural melittin and melittin I. They corroborate the presence in natural melittin of small amounts of N1-formylated melittin I. The pharmacological similarities to synthetic melittin II and N1-formylated melittin II (which have not yet been identified in the venom) argue for a broader structural basis of the melittins as a group.
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  • 6
    Electronic Resource
    Electronic Resource
    Springer
    Naunyn-Schmiedeberg's archives of pharmacology 272 (1972), S. 75-88 
    ISSN: 1432-1912
    Keywords: Tetanus Toxin ; Tetanus Antitoxin ; Local Tetanus ; Spinal Cord
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 0 1. Local tetanus was produced in rats by application of sublethal doses of 125I-tetanus toxin into the right m. gastrocnemius. Radioactivity was found in the lumbar part of the spinal cord for at least 24 days which is indicative of a long-lasting binding of toxin to its target organ. Radioactivity appears in the lumbar region before local tetanus becomes manifest. 2. The influence of antitoxin on both local tetanus and radioactivity of the lumbar cord heavily depends on the time of its application. When it is injected simultaneously into a foreleg, it prevents the symptoms and the spinal concentration process. When given ten hours after toxin, it does not change appreciably the severity of local tetanus; it diminishes, however, the radioactivity accumulating in the spinal cord. Antitoxin, given 48 hours after toxin, is ineffective in both respects. 3. 22 hours after application, about 9% of the initial radioactivity still persists in the injected leg; 50 hours after application, only 1–2% are still present. 4. Plasma radioactivity is measurable for between 50 and 96 hours in animals given 125I-toxin i.m. It is higher in animals having received antitoxin 10 hours after the toxin or simultaneously with toxin. 5. Labelled toxoid was prepared by formol treatment of labelled toxin. Following i.m. injection, toxoid was bound to a lesser degree and for a shorter time by the lumbar cord than was toxin. Like toxin, toxoid was found in the ipsilateral sciatic nerve, and simultaneous application of antitoxin prevented its appearance there as wells as in the lumbar cord. As with toxin, plasma radioactivity after injection of labelled toxoid was increased by simultaneous application of antitoxin into another leg. 6. It is concluded that antitoxin prevents the entrance of toxin into the spinal cord, but does neither remove nor detoxify appreciable amounts of radioactive material once fixed.
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  • 7
    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.
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