...Trevor W. Stone The role of the amino acid tryptophan in the generation of 5-hydroxy-tryptamine (5-HT) has been expanded over the past 30 years with recognition that its oxidation by indoleamine-2,3-dioxygenase (IDO) results in the formation of kynurenine and metabolites which regulate neuronal...

...Amanda W.S. Yeung; Andrew C. Terentis; Nicholas J.C. King; Shane R. Thomas IDO1 (indoleamine 2,3-dioxygenase 1) is a member of a unique class of mammalian haem dioxygenases that catalyse the oxidative catabolism of the least-abundant essential amino acid, L -Trp ( L -tryptophan), along...

... the degradation of the essential aromatic amino acid tryptophan via the kynurenine pathway and could contribute to deficient immune responsiveness. Activated IDO is indicated by an increased kyn/trp (kynurenine/tryptophan) ratio. The aim of the present study was to investigate whether tryptophan degradation...

... measured at rest, and during exercise and recovery. Peak oxygen uptake was significantly lower in the CFS patients compared with controls. Rating of perceived exertion in the patients was higher at all time points measured, including at rest, relative to controls. Levels of free tryptophan (free Trp...

... energy fluidity gestational hypertension Na + ,K + -ATPase placenta tryptophan 24 7 1996 2 8 1996 © 1996 The Biochemical Society and the Medical Research Society 1996 Clinical Science (I 996) 9 I, 7 19-723 (Printed in Great Britain) 719 Na t t ,K -ATPase of human placenta...

...Roger J. W. Truscott; Anthony J. Elderfield 1. Cataract is the single major cause of blindness worldwide; however, the reasons for the development of this condition remain unknown. It has been suggested that the essential amino acid tryptophan may be implicated in the aetiology but definitive...

...-hydroxytryptamine by oral dosing with its precursor, L-tryptophan (2 g), in nine patients with essential hypertension and in six subjects with normotension. 2. Before tryptophan administration, urinary excretion of 5-hydroxytryptamine was significantly higher in the hypertensive group than in the normotensive group...

...V. Gentil; M. H. Lader; B. D. Kantamaneni; G. Curzon 1. Subcutaneous injection of adrenaline into normal male volunteer subjects caused large increases of plasma non-esterified fatty acids and free tryptophan, but plasma total tryptophan fell considerably. Therefore increases of the percentage...

... the groups was abolished. 4. Total plasma tryptophan concentrations were equal in the two groups. Free plasma tryptophan, however, was markedly reduced in the choreic group, and this appeared to be a result of a disturbed relationship between free tryptophan and NEFA concentrations. The abnormalities in free...

...G. Curzon; June Friedel; Bharati D. Katamaneni; Monica H. Greenwood; M. H. Lader 1. The percentage of human plasma tryptophan in the free state (ultrafilterable) was positively and significantly correlated with plasma non-esterified fatty acid (NEFA) concentration. 2. Results obtained either...

... and methionine were observed. 3. Altered concentrations in plasma of neutral amino acids which compete with tryptophan for transport into the brain had no apparent influence on brain tryptophan concentration. 17 12 1973 © 1974 The Biochemical Society and the Medical Research Society 1974 amino...

...D. P. Rose; R. Strong; P. W. Adams; P. E. Harding 1. A vitamin B 6 -deficient diet was fed to an adult male subject to confirm previously described changes in tryptophan metabolism and urinary 4-pyridoxic acid excretion, and erythrocyte alanine and aspartate aminotransferase activities. 2...