Linked Life Data

2569904

Source:http://linkedlifedata.com/resource/pubmed/id/2569904

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1989-9-25
pubmed:abstractText
The uptake of gamma-aminobutyric acid (GABA) and L-glutamic acid by synaptosomes prepared from frozen postmortem human brain was shown to be effected via distinct high and low affinity sites. At approximately 17 h postmortem delay, the kinetic parameters for GABA uptake were: high affinity site, Km 7.1 +/- 2.5 microM, Vmax 18.7 +/- 4.8 nmol.min-1 per 100 mg protein; low affinity site, Km 2 +/- 1 mM, Vmax 425 +/- 250 nmol.min-1 per 100 mg protein (means +/- S.E.M., n = 13). Kinetic parameters for L-glutamate uptake were: high affinity site, Km 7.5 +/- 1.0 microM, Vmax 85 +/- 8 nmol.min-1 per 100 mg protein; low affinity site, Km 1.8 +/- 1.2 mM. Vmax 780 +/- 175 nmol.min-1 per 100 mg protein (n = 11). A detailed kinetic analysis of high affinity GABA uptake was performed over a range of sodium ion concentrations. The results were consistent with a coupling ratio of one Na+ ion to one GABA molecule; a similar result was found with rat brain synaptosomes. However, rat and human synaptosomes differed in the degree to which the substrate affinity of the high affinity GABA uptake site varied with decreasing Na+ ion concentration. High affinity GABA uptake was markedly affected by the method used to freeze and divide the tissue, but did not vary greatly in different cortical regions. There was some decline of high affinity GABA uptake activity with postmortem delay, apparently due to a loss of sites rather than a change in site affinity.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0006-8993
pubmed:author
pubmed:issnType
Print
pubmed:day
26
pubmed:volume
490
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
320-31
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1989
pubmed:articleTitle
Uptake of gamma-aminobutyric acid and L-glutamic acid by synaptosomes from postmortem human cerebral cortex: multiple sites, sodium dependence and effect of tissue preparation.
pubmed:affiliation
Department of Pharmacology, University of Sydney, N.S.W., Australia.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't