Linked Life Data

2571097

Source:http://linkedlifedata.com/resource/pubmed/id/2571097

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
7
pubmed:dateCreated
1989-10-20
pubmed:abstractText
Ca2+ uptake was measured in purified rat cerebral cortex synaptosomes (P3 pellets) using 45Ca2+ as a tracer. Ca2+ influx increased in time, and with an increase in external K+ concentration and temperature. The net (external K+-induced, depolarization-dependent) uptake follows a two-component course. The exponential term, due to the opening of voltage-operated calcium channels (VOC), has a rate constant which increases with an increase in the depolarization level (1.04 versus 0.54 nmol/s/mg protein for 50 mM - versus 15 mM [K+]-dependent net influx). The linear term, due to the Na+/Ca2+ exchange system, has a similar rate constant at all depolarization levels (0.16 +/- 0.05 and 0.11 +/- 0.02 nmol/s/mg protein). Excitatory amino acids (glutamate, kainate and n-methyl-d-aspartate-NMDA-) were tested on this preparation at doses ranging between 5 x 10(-5) M and 5 x 10(-3) M and at multiple incubation times, under resting conditions and under two depolarizing conditions (partial depolarization: 15 mM external K+ and maximal depolarization: 50 mM external K+). NMDA was also tested in the absence of Mg2+. No effect was detectable under any of these experimental conditions. Hypotheses to interpret these data are discussed. Further studies on other preparations are needed in order to directly investigate the presynaptic effects of excitatory amino acids.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0364-3190
pubmed:author
pubmed:issnType
Print
pubmed:volume
14
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
677-82
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1989
pubmed:articleTitle
Lack of excitatory amino acid-induced effects on calcium fluxes measured with 45Ca2+ in rat cerebral cortex synaptosomes.
pubmed:affiliation
Institute of Pharmacology, University of Ferrara, Italy.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't