Linked Life Data

10822500

Source:http://linkedlifedata.com/resource/pubmed/id/10822500

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
2000-6-21
pubmed:abstractText
Potassium-stimulated 45Ca entry into rat brain synaptosomes was measured at times ranging from 1 to 60 s. The K-rich solutions were used to depolarize the synaptosomes. Backflux of 45Ca from the synaptosomes was negligible during the first 10-20 s of incubation. An initial ("fast") phase of K-stimulated Ca entry, lasting from 1 to 2 s was observed. This phase was inhibited by low concentrations of La (KI approximately equal to 0.3 microM). It was also abolished ("inactivated") by incubating the synaptosomes in depolarizing solutions (containing veratridine, gramicidin, or elevated [K]o) before the addition of 45Ca. An additional long lasting ("slow") phase of K-stimulated Ca entry was also detected. This "slow" Ca entry was much less sensitive to La (KI > 100 microM) and was not affected by depolarizing the synaptosomes before the addition of 45Ca. The rate of influx during the fast phase was about four times the rate of Ca influx during the slow phase. Neither the fast nor slow phase of Ca entry was sensitive to tetrodotoxin (10 microM), a potent blocker of Na channels, but both phases were inhibited by Ni, Mn, Mg, and other agents that block Ca channels. The data are consistent with the presence of two distinct populations of voltage-regulated, divalent cation-selective pathways for Ca entry in presynaptic brain nerve endings.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0022-1295
pubmed:author
pubmed:issnType
Print
pubmed:volume
76
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
709-28
pubmed:dateRevised
2008-11-20
pubmed:meshHeading
pubmed:year
1980
pubmed:articleTitle
Some properties of potassium-stimulated calcium influx in presynaptic nerve endings.
pubmed:affiliation
Department of Physiology, University of Maryland School of Medicine, Baltimore 21201, USA.
pubmed:publicationType
Journal Article, In Vitro, Research Support, U.S. Gov't, P.H.S.