Linked Life Data

7409205

Source:http://linkedlifedata.com/resource/pubmed/id/7409205

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
10
pubmed:dateCreated
1980-11-20
pubmed:abstractText
The nonmitochondrial ATP-dependent calcium sequestration site within "pinched-off" presynaptic nerve terminals (synaptosomes) was localized by morphological techniques. The terminals contain mitochondria, smooth endoplasmic reticulum (SER), synaptic vesicles, and occasional coated vesicles. Three-dimensional reconstructions of serial sections of synaptosomes reveal that the SER consists, in part, of flattened sacs or cisterns often situated adjacent to mitochondria. Synaptosomes with leaky plasma membranes (induced by saponin treatment) were incubated in physiological salt solutions containing Ca, ATP, and oxalate to promote Ca sequestration. After incubation in these solutions, synaptosomes contained electron-dense deposits, presumably calcium oxalate, localized within mitochondria, SER cisterns, and vesicular profiles. Electron probe microanalyses of these electron-dense deposits confirmed the presence of calcium. When mitochondrial poisons were included in the incubation media, electron-dense deposits were still observed in the SER; however, under these conditions, mitochondria very rarely contained such deposits. When A23187 or EGTA was included in the incubation solutions, electron-dense deposits rarely were observed in any organelles within the terminals. When oxalate was omitted from the incubation media, no electron-dense deposits were found in the synaptosomes. These results show that the nerve terminal SER is capable of sequestering Ca. The data are consistent with biochemical and physiological evidence that the SER plays a significant role in intraterminal Ca buffering during neuronal activity.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0014-9446
pubmed:author
pubmed:issnType
Print
pubmed:volume
39
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2796-801
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1980
pubmed:articleTitle
Probing for calcium at presynaptic nerve terminals.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.