Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1-2
pubmed:dateCreated
2004-2-4
pubmed:abstractText
Severe hyperhomocysteinemia (50-200 microM) often presents itself with acute neuronal dysfunction including seizures and psychosis. Its moderate form (15-50 microM) is associated with cognitive impairment and dementia. We investigated the neuropharmacological effects of homocysteine and its oxidized forms, homocysteinesulfinic acid (HCSA) and homocysteic acid (HCA), on neuronal network function utilizing dissociated cortical neurons from embryonic Wistar rats on microelectrode arrays. All substances inhibited dose-dependently and reversibly spontaneous neuronal network activity within seconds: L-HCSA and L-HCA blocked spontaneous spike rate (SSR) significantly at very low concentrations, with an IC50 of 1.9 and 1.3 microM, respectively; whereas the dose-response curve of D,L-homocysteine revealed an IC50 of 401 microM. These effects were antagonized by 2-amino-5-phosphonovaleric acid (APV) pointing to the NMDA receptor as mediator of this fast and reversible inhibition of network activity. We conclude that a neuronal dysfunction observed in hyperhomocysteinemia is likely due to HCSA and HCA since effective concentrations of homocysteine are not reached in patients.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0022-510X
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
218
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
109-14
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed-meshheading:14759642-Action Potentials, pubmed-meshheading:14759642-Animals, pubmed-meshheading:14759642-Cells, Cultured, pubmed-meshheading:14759642-Dose-Response Relationship, Drug, pubmed-meshheading:14759642-Drug Combinations, pubmed-meshheading:14759642-Drug Interactions, pubmed-meshheading:14759642-Electric Stimulation, pubmed-meshheading:14759642-Electrophysiology, pubmed-meshheading:14759642-Embryo, Mammalian, pubmed-meshheading:14759642-Homocysteine, pubmed-meshheading:14759642-Hyperhomocysteinemia, pubmed-meshheading:14759642-N-Methylaspartate, pubmed-meshheading:14759642-Neocortex, pubmed-meshheading:14759642-Nerve Net, pubmed-meshheading:14759642-Neural Inhibition, pubmed-meshheading:14759642-Rats, pubmed-meshheading:14759642-Rats, Wistar, pubmed-meshheading:14759642-Valine
pubmed:year
2004
pubmed:articleTitle
Implications for hyperhomocysteinemia: not homocysteine but its oxidized forms strongly inhibit neuronal network activity.
pubmed:affiliation
Department of Neurology, Heinrich-Heine University, Düsseldorf, Germany.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't