Administration of D-alanine did not cause increase of D-amino acid oxidase activity in mice

D-amino acid oxidase (DAAO) activity was not altered in the liver and kidney by oral administration of D-alanine to adult mice. The enzyme was apparently not induced by the enteric microflora either, since the enzyme activity in the liver and kidney of germ-free mice was not different from that of specific-pathogen-free mice. The times of appearance of DAAO activity and of free D-amino acids in the kidney were elucidated using suckling mice. DAAO activity started to increase 7 days after birth, and reached almost the adult level by 28 days. The content of free neutral D-amino acids also increased with age, in a similar fashion. A possible conclusion is that the enzyme activity normally increases during this period, to eliminate the free D-amino acids which have increased with age in the suckling mice. Consequently, the administration of D-alanine had no further effect in increasing enzyme activity.     

D-aspartate oxidase activity and D-aspartate content in a mutant mouse strain lacking D-amino acid oxidase

A mutant mouse strain ddY/DAO- lacks D-amino acid oxidase activity and accumulates free neutral D-amino acids in its tissues. In this study, D-aspartate oxidase activity and D-aspartate content in the tissues of these mutant mice were compared with those of normal mice. No significant difference was observed, indicating that the metabolism of acidic D-amino acids was unaffected in the mutant.     

D-Aspartate oxidase activity and D-aspartate content in a mutant mouse strain lacking D-amino acid oxidase

Summary A mutant mouse strain ddY/DAO^– lacks D-amino acid oxidase activity and accumulates free neutral D-amino acids in its tissues. In this study, D-aspartate oxidase activity and D-aspartate content in the tissues of these mutant mice were compared with those of normal mice. No significant difference was observed, indicating that the metabolism of acidic D-amino acids was unaffected in the mutant.     

Immunochemical studies on Rhodotorula gracilis D-amino acid oxidase.

Polyclonal antibodies were prepared from rabbit sera after immunization with holo- and apo-D-amino acid oxidase purified from R. gracilis. Both anti-holo- and anti-apoenzyme IgG fractions (as well as affinity-purified IgG) were highly specific: in blot-transfer analyses after SDS-PAGE only a 39 kDa band, corresponding to enzyme monomer, was recognized even in the partially purified yeast extract. No cross-reaction was detected with pig kidney D-amino acid oxidase. As a difference from the mammalian enzyme, yeast D-amino acid oxidase anti-holo- and anti-apoenzyme IgGs had different properties in inactivation and precipitation experiments, indicating the existence of different antigenicity sites related to the FAD-binding domain in the enzyme.     

Involvement of D-amino acid oxidase in elimination of D-serine in mouse brain.

The physiological role of D-amino acid oxidase (EC 1. 4. 3. 3) in mouse brain is described. The presence of D-enantiomers of neutral common amino acids was surveyed in the brain. D-serine was shown to be present at high concentration only in regions where the enzyme activity was low. In normal mice whose D-amino acid oxidase activity was much higher in the cerebellum than in the cerebrum, free D-serine content was apparently lower in the cerebellum than in the cerebrum. In mice of a mutant strain lacking D-amino acid-oxidase activity, the free D-serine level was remarkably high both in the cerebrum and cerebellum. The results suggest that the enzyme is involved in the elimination of free D-serine in the cerebellum.     

Involvement of D-amino acid oxidase in elimination of D-serine in mouse brain

The physiological role of D-amino acid oxidase (EC 1. 4. 3. 3) in mouse brain is described. The presence of D-enantiomers of neutral common amino acids was surveyed in the brain. D-serine was shown to be present at high concentration only in regions where the enzyme activity was low. In normal mice whose D-amino acid oxidase activity was much higher in the cerebellum than in the cerebrum, free D-serine content was apparently lower in the cerebellum than in the cerebrum. In mice of a mutant strain lacking D-amino acid-oxidase activity, the free D-serine level was remarkably high both in the cerebrum and cerebellum. The results suggest that the enzyme is involved in the elimination of free D-serine in the cerebellum.     

Ultrastructural localization of catalase and D-amino acid oxidase in 'normal' fetal mouse liver

In the hepatocytes of 'normal' fetal mice from mothers which were carriers of muscular dysgenesis, catalase and D-amino acid oxidase (DAAO) positive as well as negative peroxisomes were observed. DAAO reaction product was occasionally localized in patches around cell membranes and DAAO-positive peroxisomes were frequently observed near mitochondria.     

Mineralocorticoid treatment and the adrenalectomy-induced increase in monoamine oxidase activity

Summary Bilateral adrenalectomy in the rat results in an increase in heart monoamine oxidase activity in animals drinking water and in animals drinking 0.9% saline. Daily administration of deoxycorticosterone acetate prevented the increased monoamine oxidase activity in the animals drinking saline but not in those drinking water.Acknowledgment. This work was supported in part by a grant from the American Heart Association — Louisiana, Inc.     

Effect of phytic acid on diamine oxidase activity in germinating pea seeds.

Diamine oxidase present in the cotyledons of germinating pea seeds is induced by phytic acid but the embryo enzyme is not affected. Polyamines have no effect on phytase activity of the cotyledon or embryo.     

Influence ofp-Aminobenzoic acid on the activity of indoleacetic acid oxidase

Zusammenfassung Die enzymatische Oxydation der Indolylessigsäure bleibt durchp-Aminobenzoesäure (PABS) in vitro unbeeinflusst, während sie in vivo stark gehemmt wird. Dieser Effekt ist wahrscheinlich auf solche Inhibitoren zurückzuführen, die aus PABS in der Pflanze metabolisch entstanden sind.     

D-amino acids in mouse tissues are not of microbial origin

Neutral free D-amino acid contents in the serum, kidney, liver, brain, small intestine and urine in germ-free mice and those in specific pathogen-free mice were compared. No significant difference was found. This strongly suggests that the free D-amino acids which were shown to be present in mice in our previous work did not originate from the enteric microbial flora.     

Monoamine oxidase activity in Helix pomatia.

The distribution and characterization of MAO in various tissues of the snail were analyzed. Only low amounts of the enzyme exist in the different tissues and data suggest that there is more than one type of MAO.     

Effect of phytic acid on diamine oxidase activity in germinating pea seeds

Summary Diamine oxidase present in the cotyledons of germinating pea seeds is induced by phytic acid but the embryo enzyme is not affected. Polyamines have no effect on phytase activity of the cotyledon or embryo.We thank Dr S. K. Srivastava for his helpful suggestions.     

Tumour-promoting activity of fatty acid methyl esters in mice

Zusammenfassung Es wurden die Methylester der 12-Oxo-trans-10-octadecensäure und Hydroxyoctadecadiensäure (Produkte der Autoxidation ungesättigter Fettsäuren), sowie Methyloleat auf Mäusehaut appliziert und auf cancerogene Eigenschaften geprüft. Keiner der Ester wirkte als komplettes Carcinogen, hingegen zeigten alle Promotorwirkung. Am wirksamsten war Oxooctadecensäuremethylester, welches die Bildung von Hautpapillomen wie auch von Lymphomen förderte.

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This work wass upported by a grant from Miss Ane Martinussens Foundation, Aalborg.     

Glutamic acid dehydrogenase activity in muscles of dystrophic mice

Résumé L'activité de la déshydrogénase glutamique a été étudié dans le tissu musculaire de la souris atteinte de dystrophie musculaire héréditaire. La déhydrogénase glutamique est peu active dans le muscle dystrophique de la souris jeune, alors que l'activité de cet enzyme est fortement augmentée dans le muscle de la souris plus âgée (12–18 semaines). D'autre part, l'activité de l'enzyme est diminuée dans le muscle de la souris lorsque la maladie évolue.     

Cytochrome oxidase activity in different hypothalamic areas. Influence of castration

Resumen En el presente trabajo se ha estudiado la actividad de la citocromooxidasa en diversas areas hipotalamicas de animales machos castrados y con terapia sustitutiva. Los resultados demonstraron que la castración deprime la actividad de la enzima en el hipotálamo anterior y posterior. La posible implicancia de estos hallazgos con cambios en la cadena respiratoria producidos por la castration es discutida en el trabajo.

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Supported by Consejo Nacional de Investigaciones Científicas y Técnicas.     

Effect of retinoic acid on liver transglutaminase activity and carbon tetrachloride-induced liver damage in mice.

Transglutaminase (TGase) activity in the cytosol fraction of the mouse liver increased following intraperitoneal injection of retinoic acid. Retinoic acid inhibited the carbon tetrachloride-induced increase in serum alanine transaminase activity. These findings suggest that TGase is involved in the effect of retinoic acid on carbon tetrachloride-induced liver damage.     

Pentobarbital-induced phase shifts of circadian rhythms of locomotor activity are not mediated through stimulated activity in mice

The possibility that phase shifts of circadian rhythms of locomotor activity induced by pentobarbital injections are mediated through hyperactivity after recovery from the sedative condition was tested in DBA/2 mice. The mice were restrained for 3 h in a tube immediately after injections of pentobarbital at either CT 9 or CT 0. The results indicated that immobilization did not block the phase shifts, suggesting that pentobarbital-induced phase shifts are not due to increasing the level of activity.