Activation of liver tryptophan pyrrolase mediates the decrease in tryptophan availability to the brain after acute alcohol consumption by normal subjects.
Aims: We have previously suggested that acute ethanol consumption by normal subjects decreases the availability of circulating tryptophan (Trp) to the brain by activating liver Trp pyrrolase, the first and rate-limiting enzyme of the (major) kynurenine pathway of Trp degradation. The aim of the pres...
| Published in: | Alcohol & Alcoholism Vol. 44; no. 3; pp. 267 - 272 |
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| Main Authors: | , , , |
| Format: | Journal Article |
| Published: |
Oxford University Press / USA
May/Jun2009
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| Online Access: | View this record in EBSCOhost |
| fields | @attributes: recordID: 1 pdfLink: plink: https://search.ebscohost.com/login.aspx?direct=true&db=ccm&AN=105220346&site=ehost-live header: @attributes: shortDbName: ccm uiTerm: 105220346 longDbName: CINAHL Complete uiTag: AN controlInfo: bkinfo: dissinfo: jinfo: jid: 07350414 FA3 jtl: Alcohol & Alcoholism issn: 07350414 maglogo: N pubinfo: dt: May/Jun2009 vid: 44 iid: 3 pid: 622 pub: Oxford University Press / USA artinfo: ui: 105220346 2010258006 NLM19201692 PMC2720730 105220346 ppf: 267 ppct: 5 formats: fmt: @attributes: type: P tig: atl: Activation of liver tryptophan pyrrolase mediates the decrease in tryptophan availability to the brain after acute alcohol consumption by normal subjects. aug: au: Badawy AA Doughrty DM Marsh-Richard DM Steptoe A affil: Cardiff School of Health Sciences, University of Wales Institute Cardiff (UWIC), Wales, UK. ABadawy@uwic.ac.uk sug: subj: Alcohol Drinking Brain Metabolism Liver Tryptophan Metabolism Oxidoreductases Metabolism Adult Biological Markers Blood Brain Drug Effects Biochemical Phenomena Drug Effects Biochemical Phenomena Physiology Ethanol Administration and Dosage Female Liver Drug Effects Male Time Factors Tryptophan Blood Oxidoreductases Blood Young Adult Adult: 19-44 years Female Male ab: Aims: We have previously suggested that acute ethanol consumption by normal subjects decreases the availability of circulating tryptophan (Trp) to the brain by activating liver Trp pyrrolase, the first and rate-limiting enzyme of the (major) kynurenine pathway of Trp degradation. The aim of the present study was to examine this hypothesis further by measuring plasma levels of kynurenine metabolites following alcohol consumption. Methods: After an overnight fast and a light breakfast, each of 10 healthy subjects received one of five drinks (placebo and doses of ethanol of 0.2, 0.4, 0.6 and 0.8 g/kg body weight in tonic water) on five different occasions. Blood samples were withdrawn 2 h later and plasma was analysed for concentrations Trp, competing amino acids (CAA) and kynurenine metabolites. Results: Along with the depletion of plasma Tip and the decrease in its availability to the brain, as expressed by the ratio of [Trp]/[CAA], plasma kynurenine was elevated by doses of ethanol of 0.2-0.8 g/kg body weight. The ratio% of [kynurenine]/[Trp], an index of the expression of Tip pyrrolase activity, was also increased by all doses of ethanol. Conclusions: We conclude that activation of liver Tip pyrrolase mediates the depletion of plasma Tip and the decrease in its availability to the brain induced by acute ethanol consumption. pubtype: Academic Journal doctype: Journal Article ougenre: Article language: English refInfo: holdings: @attributes: islocal: N |
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