Linked Life Data

3676768

Source:http://linkedlifedata.com/resource/pubmed/id/3676768

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1987-12-22
pubmed:abstractText
The steady-state kinetics of choline acetyltransferase (CAT) from autopsy samples of human caudate nucleus of aged controls and of patients with Alzheimer's disease was studied. In 10 samples from Alzheimer's disease-afflicted brains the affinity for the limiting substrate choline (Ch) was significantly higher: Michaelis constant KmCh was for these samples 1.93 +/- 0.72 mM while in the samples from 9 age-matched controls KmCh was 2.53 +/- 0.78 mM. The difference is statistically significant (P less than 0.05). Endogenous choline concentrations in the samples were 124 +/- 39 (n = 10) nmol/g wet wt. in the Alzheimer's disease-afflicted samples and 180 +/- 57 (n = 9) nmol/g wet weight (n = 9) in the control samples (P less than 0.05). The initial velocity at 70 microM acetyl co-enzyme (AcCoA) in Alzheimer's samples was 171.5 +/- 131.0 pmol [14C]acetyl choline [14C]ACh/mg protein/min as compared to the controls 422.1 +/- 231.0 pmol [14C]ACh/mg protein/min replicating many previous findings about decline of CAT activity in Alzheimer's disease. However, in the same samples the affinity for the other substrate acetyl-CoA (AcCoA) was significantly lower for the Alzheimer patients, KmAcCoA = 61 +/- 40 microM, than for the age-matched control patients, KmAcCoA = 28 +/- 8 microns (P less than 0.01). The data suggest some compensation of the loss of enzyme molecules via changed affinity for the limiting substrate, Ch.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0006-8993
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
420
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
371-4
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1987
pubmed:articleTitle
Increased affinity of choline acetyltransferase for choline in Alzheimer's disease: a steady-state kinetic study.
pubmed:affiliation
Department of Biochemistry, Arrhenius Laboratory, University of Stockholm, Sweden.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't