Linked Life Data

9541167

Source:http://linkedlifedata.com/resource/pubmed/id/9541167

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1998-5-26
pubmed:abstractText
We examined the relationship between cytosolic Ca2+ concentration ([Ca2+]c) and mitochondrial matrix Ca2+ concentration ([Ca2+]m) in the pancreatic beta-cell line, MIN6. [Ca2+]c was monitored in a single or a group (30 cells) of fura-2-loaded MIN6 cells, and [Ca2+]m was measured in a group (1 x 10[6] cells) of MIN6 cells stably transfected with aequorin targeted at the mitochondria. Exogenous ATP (0.25 mmol/l) produced a single transient increase in [Ca2+]c whereas 22 mmol/l KCl produced a sustained plateau increase. ATP and KCl evoked transient increases in [Ca2+]m but with distinct time courses of [Ca2+]m decline: the [Ca2+]m increase induced by ATP decreased more rapidly than that induced by KCl. Nitrendipine (3 micromol/l), a blocker of L-type Ca2+ channels, inhibited both [Ca2+]c and [Ca2+]m signals in response to KCl and tolbutamide, but not those to ATP. Peak levels of [Ca2+]m increase (around 2 micromol/ l) exceeded those of [Ca2+]c increase (around 500 nmol/l). A rise in glucose concentration from 3 to 30 mmol/l induced oscillations of [Ca2+]c that overlay the sustained increases in [Ca2+]c in single cells. An oscillatory increase in [Ca2+]m was similarly observed in response to glucose. Addition of 10 mmol/l 2-ketoisocaproic acid at 20 mmol/l glucose further increased the plateau level of [Ca2+]c and the frequency of [Ca2+]c oscillations, which were correlated with a further increase in [Ca2+]m. In response to pulsatile exposure to KCl, [Ca2+]c and [Ca2+]m increased synchronously. These data suggest that an oscillatory increase in [Ca2+]m in beta cells, the signal which is thought to be necessary for continuous stimulation of mitochondrial metabolism, is produced synchronously with the [Ca2+]c oscillations.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0012-186X
pubmed:author
pubmed:issnType
Print
pubmed:volume
41
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
279-86
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:9541167-Adenosine Triphosphate, pubmed-meshheading:9541167-Aequorin, pubmed-meshheading:9541167-Animals, pubmed-meshheading:9541167-Calcium, pubmed-meshheading:9541167-Calcium Channels, pubmed-meshheading:9541167-Cell Line, pubmed-meshheading:9541167-Chelating Agents, pubmed-meshheading:9541167-Cytosol, pubmed-meshheading:9541167-DNA Probes, pubmed-meshheading:9541167-Dose-Response Relationship, Drug, pubmed-meshheading:9541167-Fluorescent Dyes, pubmed-meshheading:9541167-Fura-2, pubmed-meshheading:9541167-Glucose, pubmed-meshheading:9541167-Hypoglycemic Agents, pubmed-meshheading:9541167-Islets of Langerhans, pubmed-meshheading:9541167-Mitochondria, pubmed-meshheading:9541167-Potassium Chloride, pubmed-meshheading:9541167-Signal Transduction, pubmed-meshheading:9541167-Tolbutamide
pubmed:year
1998
pubmed:articleTitle
Repetitive mitochondrial Ca2+ signals synchronize with cytosolic Ca2+ oscillations in the pancreatic beta-cell line, MIN6.
pubmed:affiliation
First Department of Internal Medicine, Faculty of Medicine, Kagoshima University, Japan.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't