Results 141 to 150 of about 1,078 (162)
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Neurochemical Research, 1976
Intraperitoneally injected [(14)C]biopterin (B), dihydrobiopterin (BH2), and tetrahydrobiopterin (BH4) penetrated the brain rapidly, but in amounts sufficient to represent only a minor source of supply. Unlike isobiopterin, B was rapidly reduced to BH2 in brain.
Gál Em, Hanson G, Sherman A
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Intraperitoneally injected [(14)C]biopterin (B), dihydrobiopterin (BH2), and tetrahydrobiopterin (BH4) penetrated the brain rapidly, but in amounts sufficient to represent only a minor source of supply. Unlike isobiopterin, B was rapidly reduced to BH2 in brain.
Gál Em, Hanson G, Sherman A
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Hyperphenylalaninaemia caused by defects in biopterin metabolism
Journal of Inherited Metabolic Disease, 1985AbstractThe hepatic phenylalanine hydroxylating system consists of three essential components, phenylalanine hydroxylase, dihydropteridine reductase and the non‐protein coenzyme, tetrahydrobiopterin. The reductase and the pterin coenzyme are also essential components of the tyrosine and tryptophan hydroxylating systems.
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Plasma biopterin levels and tetrahydrobiopterin responsiveness
Molecular Genetics and Metabolism, 2005Tetrahydrobiopterin (BH4) responsive hyperphenylalaninemia (HPA) with a mutant phenylalanine hydroxylase (PAH) gene was found during neonatal screening for PKU. This study determined blood BH4 and phenylalanine in two patients with hyperphenylalaninemia following oral load with BH4 10 mg/kg. Our patients underwent neonatal screening for PKU, had normal
Minoru Asada +4 more
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Nitric oxide and biopterin in depression and stress
Psychiatry Research, 1999Depression has been hypothesized to be related to the reduced biosynthesis of neurotransmitters such as serotonin, noradrenalin and dopamine. Much past research has also been devoted to dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis in depression.
van Amsterdam, JGC, Opperhuizen, A
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Life Sciences, 1984
Levels of GTP cyclohydrolase, neopterin and biopterin were determined in tissues and body fluids of humans, monkey, dog and mouse. Highest levels of GTP cyclohydrolase and biopterin were found in pineal, liver, spleen, bone marrow, whole adrenal gland and small intestine. High levels of biopterin were found in the urine of all species examined.
David S. Duch +3 more
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Levels of GTP cyclohydrolase, neopterin and biopterin were determined in tissues and body fluids of humans, monkey, dog and mouse. Highest levels of GTP cyclohydrolase and biopterin were found in pineal, liver, spleen, bone marrow, whole adrenal gland and small intestine. High levels of biopterin were found in the urine of all species examined.
David S. Duch +3 more
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A differential microdetermination for the various forms of biopterin
Analytical Biochemistry, 1978Abstract Conditions for the quantitative oxidation and destruction of tetrahydrobiopterin and quinoid dihydrobiopterin and the separation of biopterin from its reduced forms by ECTEOLA-Sephadex column chromatography are described. A procedure for the quantitation of tetrahydrobiopterin plus quinoid dihydrobiopterin, 7,8-dihydrobiopterin, and ...
Isao Eto +3 more
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Neopterin and Biopterin Levels in Pregnancy
2002The roles of nitric oxide in pregnancy have been shown to regulate vascular tone to fit with the hemodynamic changes characterizing pregnancy and to modulate uterine contractility (1,2,3). The activity of nitric oxide synthase is dependent on the availability of cofactors including tetrahydrobiopterin (BH4) (4). The precise role of BH4 is not yet known.
Naoko Iwanaga +11 more
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New aspects in biopterin biosyntheses
1981A human kidney preparation which catalyzes the conversion of D-erythro-dihydroneopterin triphosphate (NeH2P3) to dihydrobiopterin (BH2), sepiapterin, pyruvate and pterin in the presence of Mg++ and NADPH was studied. After incubation with NeH2P3, the formation of Tanaka’s compound X (probably 6-(1’,2’-dioxopropyl)-7,8-dihydropterin) could be proven as ...
Curtius Hc +4 more
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Progress in Phenylketonuria: Defects in the Metabolism of Biopterin
Pediatrics, 1980Although progress in a major biological frontier, the neurosciences, has been both rapid and broadly based, it has offered little to the practical pediatrician. Some recent reports may forecast a change. Careful study of an old subject, phenylketonuria (PKU), has opened up a new area of research that has great potential significance ...
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Reindarstellung von Biopterin und 7-Biopterin
Hoppe-Seyler´s Zeitschrift für physiologische Chemie, 1962H Metzger, H Rembold
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