Linked Life Data

10066818

Source:http://linkedlifedata.com/resource/pubmed/id/10066818

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
11
pubmed:dateCreated
1999-4-13
pubmed:abstractText
GH3 cells showed spontaneous rhythmic oscillations in intracellular calcium concentration ([Ca2+]i) and spontaneous prolactin release. The L-type Ca2+ channel inhibitor nimodipine reduced the frequency of Ca2+ oscillations at lower concentrations (100nM-1 microM), whereas at higher concentrations (10 microM), it completely abolished them. Ca2+ oscillations persisted following exposure to thapsigargin, indicating that inositol 1,4,5-trisphosphate-sensitive intracellular Ca2+ stores were not required for spontaneous activity. The K+ channel inhibitors Ba2+, Cs+, and tetraethylammonium (TEA) had distinct effects on different K+ currents, as well as on Ca2+ oscillations and prolactin release. Cs+ inhibited the inward rectifier K+ current (KIR) and increased the frequency of Ca2+ oscillations. TEA inhibited outward K+ currents activated at voltages above -40 mV (grouped within the category of Ca2+ and voltage-activated currents, KCa,V) and increased the amplitude of Ca2+ oscillations. Ba2+ inhibited both KIR and KCa,V and increased both the amplitude and the frequency of Ca2+ oscillations. Prolactin release was increased by Ba2+ and Cs+ but not by TEA. These results indicate that L-type Ca2+ channels and KIR channels modulate the frequency of Ca2+ oscillations and prolactin release, whereas TEA-sensitive KCa,V channels modulate the amplitude of Ca2+ oscillations without altering prolactin release. Differential regulation of these channels can produce frequency or amplitude modulation of calcium signaling that stimulates specific pituitary cell functions.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
12
pubmed:volume
274
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
7508-15
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1999
pubmed:articleTitle
L-type Ca2+ channels and K+ channels specifically modulate the frequency and amplitude of spontaneous Ca2+ oscillations and have distinct roles in prolactin release in GH3 cells.
pubmed:affiliation
Department of Neurology, UCLA School of Medicine, Los Angeles, California 90095, USA. acharles@ucla.edu
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.