Linked Life Data

9755084

Source:http://linkedlifedata.com/resource/pubmed/id/9755084

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4 Pt 1
pubmed:dateCreated
1998-11-23
pubmed:abstractText
Membrane capacitance (Cm) was measured as an index of exocytosis in human growth hormone-secreting adenoma cells using the perforated whole cell, patch-clamp technique; the effects of membrane depolarization, growth hormone-releasing hormone, and 8-bromoadenosine 3',5'-cyclic monophosphate (8-BrcAMP) were examined. Cm was increased by membrane depolarization to potentials beyond the threshold necessary to open voltage-gated Ca2+ channels. These voltage-dependent changes in Cm varied as a function of both depolarization amplitude and duration and were blocked in the presence of the Ca2+ channel antagonist nitrendipine (10(-6) M). When membrane potential was clamped at the holding potential (-78 mV), voltage-gated Ca2+ channels were closed, and neither application of growth hormone-releasing hormone nor 8-BrcAMP affected Cm. However, when these agents were applied to depolarized cells, where the voltage-gated Ca2+ channels were open, the increases in Cm were augmented. From these data, it was concluded that elevation of intracellular cAMP, per se, did not stimulate exocytosis. Rather, Ca2+ influx through voltage-gated channels was a prerequisite for cAMP-induced exocytosis.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0002-9513
pubmed:author
pubmed:issnType
Print
pubmed:volume
275
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
E649-54
pubmed:dateRevised
2004-11-17
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Effect of Ca2+ and cAMP on capacitance-measured hormone secretion in human GH-secreting adenoma cells.
pubmed:affiliation
Fourth Department of Internal Medicine, Tokyo University Branch Hospital, Tokyo 112, Japan.
pubmed:publicationType
Journal Article