Methämoglobinbildung durch Röntgen‐Bestrahlung in Hämolysat und intakten Erythrocyten von verschiedenem Katalysegehalt

Heiniger, J. P.; Aebi, H.

doi:10.1002/hlca.19630460125

Cited by 8 publications

(4 citation statements)

References 15 publications

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“…Presumably under usual conditions as little enzyme as found in cells of acatalasia cases may be sufficient. However, as shown previously, this is not the case under special circumstances, such as in in vitro irradiation experiments [4,23].…”

Section: Discussionmentioning

confidence: 81%

“…been presented by Warburg et al [50], and by this group [4,23], the importance of glutathione peroxidase in this respect has been pointed out by Mills [33,34] and by Cohen and Hochstein [15]. Both enzymes exert their protective action by removal of excess H202, as shown in the diagram (Fig.…”

Section: (4) Glutathione Level Methemoglobin-and Choleglobin-formatimentioning

confidence: 88%

“…Such a role might be e. g. destruction of excess H202 produced by certain oxidative enzymes [5,8,41] or by ionizing irradiation [23]. For this type of activity very little enzyme would be required, because of the extraordinary high turnover of catalatic ( = H202-splitting) activity.…”

Section: Discussionmentioning

confidence: 99%

“…The extent to which either enzyme contributes to this effect, can be estimated experimentally by blocking one of them and checking the activity of the remaining enzyme by adding reagent-H202 at a constant rate. The role of catalase is best seen, if methemoglobin formation in normal and "acatalatic" cells is compared after addition of reagent H202 [23], after irradiation [4,23] or when the cells are incubated in presence of Notatin and Glucose [24]. In all instances there is a cor relation between the amount of methemoglobin formed and catalase activity.…”

Section: (4) Glutathione Level Methemoglobin-and Choleglobin-formatimentioning

confidence: 99%

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Observations in two Swiss Families with Acatalasia II

Aebi¹,

Baggiolini²,

Dewald³

et al. 1964

Enzymol Biol Clin

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(1) Red cells from acatalatic humans contain a small amount of catalase activity (0.1—1.3% of normal). By means of gel-filtration this material has been isolated and its properties compared with catalase from normal human red cells. Preparations from either source are identical in respect to (a) elution velocity on Sephadex G-100 column, (b) electrophoretic mobility on starch gel, (c) sensitivity towards azide and (d) precipitation in the Ouchterlony-test by anti-catalase serum. Based on these observations acatalasia is likely to be a "controller gene disease" rather than a structural gene defect. (2) The enzyme is lacking not only in red and white blood cells, but also in liver, skin, lymphoepithelial tissue and explanted fibroblasts. In contrast to East-Asian cases in Swiss acatalasia families no oral affections (gangraena) are observed and activity levels in the blood of heterozygotes vary to a much greater extent. (3) In loading test with formate (5 g orally in a single dose) normal and acatalatic subjects behave the same way. In either case formate is rapidly oxidized and only a few percent are excreted unchanged in urine. Based on similar experiments with 14C-formate in normal and germ-free rats this is considered as evidence that bacterial catalase effectively compensates the enzyme defect and therefore enables the acatalatic to perform oxidations due to peroxidatic catalase activity.

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Section: Discussionmentioning

confidence: 81%

Section: (4) Glutathione Level Methemoglobin-and Choleglobin-formatimentioning

confidence: 88%

Section: Discussionmentioning

confidence: 99%

Section: (4) Glutathione Level Methemoglobin-and Choleglobin-formatimentioning

confidence: 99%

See 2 more Smart Citations

Observations in two Swiss Families with Acatalasia II

Aebi¹,

Baggiolini²,

Dewald³

et al. 1964

Enzymol Biol Clin

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Methämoglobinbildung in Erythrocyten durch Peroxideinwirkung. Versuche zur Beurteilung der Schutzfunktion von Katalase und Glutathionperoxidase

Aebi

Heiniger

Lauber

1964

Helvetica Chimica Acta

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The rate of methaemoglobin formation induced by small amounts of H2O2, a) generated enzymatically, or (b) added by diffusion as vapour, has been investigated in suspensions of normal and acatalasic red cells. At low rates of H2O2‐generation (i.e. 10−10−10−9 moles H2O2/mg Hgb/min) removal of H2O2 is mainly due to glutathione peroxidase activity, whereas at higher rates (i.e. 10−9−10−7 moles H2O2/mg Hgb/min) catalase activity is responsible for haemoglobin protection. Under the latter experimental conditions the yield of methaemoglobin formcd depends mainly on red cell catalase activity. The existence of a lag‐phase in methaemoglobin formation and measurements of reduced glutathione concentration suggest that catalase and haemoglobin compete for excess H2O2 only after the intracellular supply of reduced glutathione has been exhausted and the H2O2 concentration in the cells has passed a critical level of than 7 · 10−6MH2O2.

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Peroxidbildung bei der Autoxydation N²‐substituierter Methylhydrazine

Aebi

Dewald

Suter

1965

Helvetica Chimica Acta

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The isolation of ergosine und ergosinine as well as agroclavine from seeds of Ipomoea argyro@hylla VATKE is described. This is the first case where ergot alkaloids of the peptide type have been found in higher plants.In Gegenwart eines geeigneten Katalysators werden Methylhydrazin-verbindungen bei neutraler Reaktion rasch zum entsprechenden Azoderivat oxydiert, wobei gleichzeitig H,O, bzw. peroxid-aquivalente Produkte (Radikale) entstehen [l]. In einer vorangehenden Arbeit ist die Oxydation verschiedener N2-substituierter Methylhydrazine, speziell solcher mit cytostatischer Wirkung, unter verschiedenen Versuchsbedingungen manometrisch verfolgt worden [I a]. Dabei hat sich am Beispiel von l-Methyl-2-[p-(isopropyl-carbamoyl)-benzyl]-hydrazin-HC1 (= Methylhydrazin I)1) gezeigt , dass neben verschiedenen Schwermetall-Ionen (z. B. Cu2+, Co2+, V3+, Mn2+) auch komplexe Eisenverbindungen (z. B. Fe-EDTA, Ferritin, Myoglobin) recht wirksame Katalysatoren dieses Oxydationsvorganges sind. Da sich unter diesen mehrere befinden, die im Organismus ubiquitar vorkommen, besteht die Moglichkeit, dass auch die ilz vivo auftretende Dehydrogenierung der Methylhydrazine (RAAF-LAUB & SCHWARTZ [ 2 ] ) wenigstens teilweise auf einer Schwermetall-Katalyse beruht. Von den bisher untersuchten Katalysatoren der Methylhydrazin-Oxydation weisen die meisten auch eine mehr oder weniger ausgepragte Katalase-bzw. Peroxidase-Aktivitat auf. Zahlreiche Schwermetallverbindungen bewirkenbesonders wenn an einen geeigneten Trager adsorbiertbereits in geringer Konzentration (ca. l o -7~) eine starke Beschleunigung der H,O,-Spaltung ((( Katalase-Modelle D von KRAUSE [3]). l) Markcnname NATULAN (({Roche)))

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Methämoglobinbildung durch Röntgen‐Bestrahlung in Hämolysat und intakten Erythrocyten von verschiedenem Katalysegehalt

Abstract: A short review is given on published rotatory dispersion data of 60 trivalent chromium and cobalt coordination compounds. Own measurements are reported on 16 compounds. The most important facts of theory and interpretation are reviewed.

Cited by 8 publications

References 15 publications

Observations in two Swiss Families with Acatalasia II

Observations in two Swiss Families with Acatalasia II

Methämoglobinbildung in Erythrocyten durch Peroxideinwirkung. Versuche zur Beurteilung der Schutzfunktion von Katalase und Glutathionperoxidase

Peroxidbildung bei der Autoxydation N²‐substituierter Methylhydrazine

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Methämoglobinbildung durch Röntgen‐Bestrahlung in Hämolysat und intakten Erythrocyten von verschiedenem Katalysegehalt

Abstract: A short review is given on published rotatory dispersion data of 60 trivalent chromium and cobalt coordination compounds. Own measurements are reported on 16 compounds. The most important facts of theory and interpretation are reviewed.

Cited by 8 publications

References 15 publications

Observations in two Swiss Families with Acatalasia II

Observations in two Swiss Families with Acatalasia II

Methämoglobinbildung in Erythrocyten durch Peroxideinwirkung. Versuche zur Beurteilung der Schutzfunktion von Katalase und Glutathionperoxidase

Peroxidbildung bei der Autoxydation N2‐substituierter Methylhydrazine

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Peroxidbildung bei der Autoxydation N²‐substituierter Methylhydrazine