Linked Life Data

8750601

Source:http://linkedlifedata.com/resource/pubmed/id/8750601

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
1996-10-16
pubmed:abstractText
Blood-brain barrier permeability to phenylalanine and leucine in four patients with phenylketonuria and in four volunteers was measured five times by the double-indicator method at increasing plasma concentrations of phenylalanine. Based on the permeability-surface area product (PS) from blood to brain (PS1) and on plasma phenylalanine levels, Vmax and the apparent Km for phenylalanine were determined. Statistically significant relationships between plasma phenylalanine and PS1 were established in three out of four volunteers, the average Vmax value being 46.7 nmol/g per min and the apparent Km 0.328 mmol/L. Owing to saturation of the carrier, such a relationship could not be established in the patients. In phenylketonuria, PS1 for phenylalanine and leucine decreased significantly by 55% and 46%, respectively. Transport from brain back to blood, PS2, decreased significantly and cerebral large neutral amino acid net uptake was generally decreased in patients with phenylketonuria. In conclusion, the transport of L-phenylalanine across the human blood-brain barrier follows Michaelis-Menten kinetics. In phenylketonuria, brain permeability to large neutral amino acids is reduced by about 50% and net uptake appears decreased.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0141-8955
pubmed:author
pubmed:issnType
Print
pubmed:volume
18
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
653-64
pubmed:dateRevised
2007-3-21
pubmed:meshHeading
pubmed:year
1995
pubmed:articleTitle
Blood-brain barrier transport of amino acids in healthy controls and in patients with phenylketonuria.
pubmed:affiliation
Department of Neurology, University Hospital Rigshospitalet, Copenhagen, Denmark.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't