Linked Life Data

2454918

Source:http://linkedlifedata.com/resource/pubmed/id/2454918

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
20
pubmed:dateCreated
1988-8-8
pubmed:abstractText
A novel combination of two single cell assays allowed the simultaneous measurement of intracellular calcium concentration and hormone secretion in normal pituitary cells. [Ca2+]i was recorded using the fluorescent Ca2+ indicator fura-2 and digital imaging microscopy. This technique was combined with a reverse hemolytic plaque assay for growth hormone in order to identify somatotropes and quantitate the amount of hormone released. A dynamic profile of rhythmic calcium oscillations was found in spontaneously secreting somatotropes. Each somatotrope displayed a distinct frequency (one pulse every 5-30 s) and amplitude (range 50-450 nM) generated asynchronously from cell to cell. The amount of growth hormone (GH) released correlated directly with both the frequency and amplitude of calcium oscillations at the level of single GH cells. Furthermore, calcium excursions in somatotropes were rapidly suppressed by either (i) removal of extracellular calcium, (ii) somatostatin (1 mM), or (iii) the calcium channel blockers cobalt (2 mM) and verapamil (100 microM). These observations demonstrate that spontaneous calcium oscillations are characteristic for normal somatotropes. These oscillations are related to spontaneous hormone secretion and due to influx through calcium channels in the membrane. Somatostatin, the physiologic inhibitor of GH secretion, suppresses calcium transients. These findings suggest that the intracellular signaling information may be encoded both in the frequency and amplitude of calcium oscillations.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
263
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
9682-5
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1988
pubmed:articleTitle
Spontaneous oscillations of intracellular calcium and growth hormone secretion.
pubmed:affiliation
Department of Internal Medicine, University of Virginia, Charlottesville 22908.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't