Results 291 to 300 of about 20,405 (323)

Conversion of 3,4‐Dihydroxyphenylalanine and Deuterated 3,4‐Dihydroxyphenylalanine to Alcoholic Metabolites of Catecholamines in Rat Brain

Journal of Neurochemistry, 1981
Abstract: We have investigated the effects of 3,4‐dihydroxyphenylalanine l‐DOPA) and its deuterated analogue on the concentrations of alcoholic metabolites of catecholamines in rat brain by means of gas chromatography/mass spectrometry with selected‐ion monitoring.
D J, Edwards, M, Rizk
openaire   +2 more sources

The metabolism of L-3,4-dihydroxyphenylalanine in man

Clinica Chimica Acta, 1970
Abstract This study describes the metabolic fate of orally ingested l -3,4-dihydroxy-phenylalanine in four human adults. The amounts of L-DOPA ingested ranged from 3 to 8 g per day. A variety of techniques were employed whereby the acid, amine, and neutral urinary metabolites were determined.
L P, O'Gorman, O, Borud, I A, Khan, L R, Gjessing   +3 more
openaire   +2 more sources

On the presence of dihydroxyphenylalanine decarboxylase in nerves

Experientia, 1964
Durchtrennung des Ruckenmarks fuhrt zu einer Verminderung der Aktivitat des Enzymsl-3,4-Dihydroxyphenylalanin-decarboxylase (DOPA-Decarboxylase) in den kaudalen Teilen um 75% (in-vivo-Werte) bis 95% (in-vitro-Werte). Die Decarboxylaseaktivitat in der Rattenmilz wird nach Exzision des Ganglion Coeliacum ebenfalls erheblich vermindert.
N E, Andén, T, Magnusson, E, Rosengren
openaire   +2 more sources

Metabolism of Dihydroxyphenylalanine in Human Subjects

Nature, 1967
THE metabolism of dihydroxyphenylalanine (DOPA; I, R = H) may be very complex. By analogy with other amino-acids, degradation may involve decarboxylation (route A) or transamination (route B), with methylation of the 3-hydroxy group possible at any stage. The principal metabolite in normal human urine appears to be homovanillic acid (HVA; III, R = CH3),
openaire   +2 more sources

Liquid chromatographic resolution of racemic β-3,4-dihydroxyphenylalanine

Journal of Chromatography A, 1971
Abstract The d and l -isomer sof β-3,4-dihydroxyphenylalanine were effectively resolved by liquid chromatography. The separation was best accomplished using an asymmetric support prepared by bonding l -arginine through a cyanuric chloride linkage to Sephadex G-25.
R J, Baczuk, G K, Landram, R J, Dubois, H C, Dehm   +3 more
openaire   +2 more sources

Enzymatic decarboxylation of isomers and derivatives of dihydroxyphenylalanine

Archives of Biochemistry and Biophysics, 1952
Abstract 1. 1. The substrate specificities of tyrosine decarboxylase of Streptococcus faecalis R and of dihydroxyphenylalanine (DOPA) decarboxylase of pig and guinea pig kidney have been studied. 2. 2. The quantitative data reveal that interaction between substituents on the benzene ring of the substrates, as well as the position of the ...
T, SOURKES, P, HENEAGE, Y, TRANO
openaire   +2 more sources

Does 3,4-Dihydroxyphenylalanine Play a Part in Favism?

Nature, 1967
FAVISM is a haemolytic anaemia precipitated in some glucose-6-phosphate dehydrogenase (G-6-PD) deficient individuals by the ingestion of fava beans. Although the mechanism of haemolysis in G-6-PD deficient individuals has not been elucidated, it is generally thought that the destruction of reduced glutathione (GSH) is associated with the events which ...
N S, Kosower, E M, Kosower
openaire   +2 more sources

The synthesis and adhesive performance of the poly(N-benzyloxycarbonyl-3,4-dihydroxyphenylalanine) derived from 3,4-dihydroxyphenylalanine

Journal of Adhesion Science and Technology, 2013
Adhesive polymers, which contain an unusual amino acid, 3,4-dihydroxyphenylalanine (DOPA), can bind strongly to all organic or inorganic surfaces. However, due to DOPA’s poor solubility in organic solvents, it is difficult for us to get desired adhesive polymers. In this paper, poly(N-benzyloxycarbonyl-3,4-dihydroxyphenylalanine) (PNBD) was synthesized
Yihang Lv, Hui Ma, Dongdong Gao, Yi Zhong, Hong Xu, Zhiping Mao   +5 more
openaire   +1 more source

Electroencephalographic analysis of the central action of dihydroxyphenylalanine

Electroencephalography and Clinical Neurophysiology, 1970
Abstract 1. 1. The EEG effects of DOPA were analysed in cats, depending upon the level of brain-stem section. 2. 2. In contrast with cats with chronically implanted electrodes, gallamine-immobilized, and with encephale isole cats, in which DOPA is unable to induce profound changes in the EEG pattern and behaviour, this amino acid elicits an
K, Kadzielawa, E, Widy-Tyszkiewicz
openaire   +2 more sources

Chemiluminescence in the autooxidation of dihydroxyphenylalanine

Bulletin of the Academy of Sciences of the USSR Division of Chemical Science, 1972
1. In the oxidation of dihydroxyphenylalanine in alkaline medium, chemiluminescence was detected in the region of 450–600 nm with a maximum at 530 nm. The step of cyclization, leading to the formation of 5,6-dihydroxyindole, proved responsible for the luminescence. 2.
G. N. Bogdanov, V. N. Shtol'ko
openaire   +1 more source