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  • Spinal Cord  (4)
  • Peptides  (3)
  • Pharmacokinetics  (3)
  • 1
    Electronic Resource
    Electronic Resource
    Mastzelldegranulierendes Peptid (MCD-Peptid) aus Bienengift: Isolierung, biochemische und pharmakologische Eigenschaften (1968)
    Springer
    Naunyn-Schmiedeberg's archives of pharmacology 261 (1968), S. 252-270 
    Details
    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.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00536989
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  • 2
    Electronic Resource
    Electronic Resource
    Isolierung und Struktur peptischer kininliefernder Peptide aus Rinderserum (1969)
    Springer
    Naunyn-Schmiedeberg's archives of pharmacology 264 (1969), S. 172-186 
    Details
    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
    URL: http://dx.doi.org/10.1007/BF00997326
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  • 3
    Electronic Resource
    Electronic Resource
    Pharmakokinetische Besonderheiten des Tetanustoxins und ihre Beziehungen zur Pathogenese des lokalen bzw. generalisierten Tetanus (1970)
    Springer
    Naunyn-Schmiedeberg's archives of pharmacology 267 (1970), S. 1-19 
    Details
    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.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00997110
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  • 4
    Electronic Resource
    Electronic Resource
    Histoautoradiographic localisation of 125I-labeled tetanus toxin in rat spinal cord (1973)
    Springer
    Naunyn-Schmiedeberg's archives of pharmacology 280 (1973), S. 177-182 
    Details
    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.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00499178
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  • 5
    Electronic Resource
    Electronic Resource
    Metabolic fate of 125I-tetanus toxin in the spinal cord of rats and cats with early local tetanus (1977)
    Springer
    Naunyn-Schmiedeberg's archives of pharmacology 299 (1977), S. 187-196 
    Details
    ISSN: 1432-1912
    Keywords: Tetanus ; Iodine labeling ; Spinal cord ; Metabolism ; Pharmacokinetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Local tetanus was elicited in rats and cats by intramuscular injection of 125I-tetanus toxin. After different times spinal radioactivity was extracted with either non-ionic (Lubrol PX) or ionic (sodium dodecyl sulfate, SDS) detergents and compared with native or 125I-toxin by gel filtration, SDS-gel electrophoresis, immunological procedures, and toxicity tests. In double-isotope experiments, 131I-toxin was added to the extracts as standard. In rats, the bulk of extracted material was indistinguishable from native toxin. However, there was a slight shift of the extracted material towards smaller molecular weights in gel filtration with Lubrol. In gel filtration with SDS, the toxin peak was followed by some tailing of 125I radioactivity. Accordingly a small part of extracted radioactivity moves faster than the standard in SDS disc gel electrophoresis. These findings taken together indicate some degradation in vivo. Adsorption to solid-phase antibodies indicated that more than 80% of the radioactivity extracted from rats was still immunoreactive. It yielded a zone confluent with extrinsic toxin in immunodiffusion. The spinal cord Lubrol extract from rats was still toxic in the expected range. Due to the very small amounts of toxin present, no precise toxicity data could be given. In cats, there was also some evidence for radioactive split products in both SDS gel filtration and disc gel electrophoresis. The patterns closely resembled those obtained with extracts from rat spinal cord. SDS extracts from rat and cat spinal cords, poisoned with 125I tetanus toxin in vivo, were also subjected to SDS disc gel electrophoresis followign reduction with dithioerythritol (DTE). They yielded large and small chains of the same size as did native toxin. In vitro, extensive degradation with brain homogenate from rats took place at pH 3.65, but not at pH 7.5. This indicates that lysosomal degradation is not a major metabolic pathway of tetanus toxin in vivo, although it is possible in principle. It is concluded that a) unlike other toxins, tetanus toxin is not necessarily degraded during its cellular uptake, b) the bulk of radioactive material is indistinguishable, following its neuronal ascent, from native or labeled toxin, c) a part of the radioactivity is recovered as split products.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00498561
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  • 6
    Electronic Resource
    Electronic Resource
    Distribution of 125I-tetanus toxin and 125I-toxoid in rats with generalized tetanus, as influenced by antitoxin (1973)
    Springer
    Naunyn-Schmiedeberg's archives of pharmacology 276 (1973), S. 327-340 
    Details
    ISSN: 1432-1912
    Keywords: Tetanus Toxin ; Pharmacokinetics ; Central Nervous System ; Iodine Labelling ; Receptors
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In order to understand the symptomatology of generalized tetanus from the pharmacokinetics of the toxin, 125I-labelled toxin was injected i.v. in rats without and with antitoxin. 1. After a few hours latency, brain stem and spinal cord concentrate radioactive material up to the third day. The decline of radioactivity is very slow, semilogarithmic, and can be followed up to the 24th day after injection. In contrast, forebrain and cerebellum do not bind measurable radioactivity. Less than 1% of the radioactivity injected is found in the CNS. 2. The symptoms of tetanus start some time after the bulk of labelled toxin has been taken up by the CNS. They cease before all radioactivity has left it. 3. Antitoxin, given simultaneously, prevents the onset of symptoms and the uptake of radioactivity by the CNS. When given 10 h after labelled toxin, it nearly abolishes the fixation and still prevents the onset of symptoms. When given 48 h after toxin, it is nearly ineffective in both respects. Antitoxin first delays, then enhances the elimination of labelled toxin from the blood. 4. Labelled antitoxin is not enriched in the CNS. 5. The uptake of radioactivity into various parts of spinal cord corresponds well to their relative content in grey matter. 6. The pharmacokinetic behaviour of 125I-toxoid resembles that of toxin. However, in order to get measurable fixation to the CNS at least 50 times higher amounts are to be applied. It is concluded that the barrier between blood and CNS is practically impermeable to tetanus toxin. The results can be harmonized best with the assumption that generalized tetanus is nothing else than a multiple local tetanus.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00499887
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  • 7
    Electronic Resource
    Electronic Resource
    Comparative studies of native and synthetic melittins (1971)
    Springer
    Naunyn-Schmiedeberg's archives of pharmacology 270 (1971), S. 1-9 
    Details
    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.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00997294
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  • 8
    Electronic Resource
    Electronic Resource
    Distribution of 125I-tetanus toxin and 125I-toxoid in rats with local tetanus, as influenced by antitoxin (1972)
    Springer
    Naunyn-Schmiedeberg's archives of pharmacology 272 (1972), S. 75-88 
    Details
    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.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00498795
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  • 9
    Electronic Resource
    Electronic Resource
    Interaction of labelled tetanus toxin with substructures of rat spinal cord in vivo (1973)
    Springer
    Naunyn-Schmiedeberg's archives of pharmacology 276 (1973), S. 361-373 
    Details
    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
    URL: http://dx.doi.org/10.1007/BF00499889
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  • 10
    Electronic Resource
    Electronic Resource
    Biochemistry and pharmacology of the crotoxin complex (1972)
    Springer
    Naunyn-Schmiedeberg's archives of pharmacology 273 (1972), S. 313-330 
    Details
    ISSN: 1432-1912
    Keywords: Snake Venom ; Phospholipase A ; Potentiation ; Iodine Labelling ; Pharmacokinetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In order to obtain better insight into the potentiation of the toxicity of phospholipase A by crotapotin, we studied the distribution and elimination of these substances and of their combination. Blood Plasma Concentration. Iodine-labelled phospholipase A leaves the bloodstream of mice and rabbits very quickly after i.v. application. Simultaneous injection of crotapotin speeds the elimination of the enzyme. After subcutaneous application in mice the plasma concentration of phospholipase A depends on the quantity of enzyme injected. It is higher when the enzyme is complexed with crotapotin before injection. The plasma concentration of phospholipase A fails, however, to be proportional to the toxicity of the complex after subcutaneous application. Crotapotin leaves the blood of mice also very quickly after i.v. application. Organ Distribution. After i.v. application in mice, phospholipase A is heavily enriched in the liver. By simultaneous application of crotapotin, the enzyme is partially diverted to the kidneys. Only a small percentage of injected enzyme is found in the brain. This percentage is just significantly raised by simultaneous application of crotapotin. The diaphragm contains about the twofold amount of phospholipase A per wet weight as compared with other samples of skeletal musculature. With crotapotin, there is a slight increase of the radioactivity in all muscles investigated, with different degrees of significance. Crotapotin is enriched in mouse kidneys after i.v. application. Renal Elimination. The renal elimination of the acidic crotapotin is higher than that of the basic phospholipase A. In this respect, the latter resembles the basic polypeptide Trasylol®. Doses of phospholipase A above 0.25 mg/kg cause intravital hemolysis. The hemolysis is prevented if a small amount of crotapotin is applied simultaneously. Our findings show that the combination with crotapotin distinctly alters the pharmacokinetic behaviour of Crotalus terrificus phospholipase A. However, our data do not explain the tremendous increase of phospholipase A toxicity caused by the non-toxic crotapotin.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00499666
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