Linked Life Data

1586942

Source:http://linkedlifedata.com/resource/pubmed/id/1586942

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1992-6-25
pubmed:abstractText
The effects of thapsigargin on intracellular Ca2+ concentration ([Ca2+]i) and progesterone production were determined in granulosa cells from the two largest preovulatory follicles of laying hens. [Ca2+]i was measured in cells loaded with the Ca(2+)-responsive fluorescent dye Fura-2. Thapsigargin stimulated a 4.6 +/- 0.2-fold increase in [Ca2+]i from a resting level of 55 +/- 6 nM up to 233 +/- 23 nM (n = 8) in 100% of the cells tested (n = 86). However, two different response patterns were observed. Dependent on the cell populations, a maximally effective concentration of thapsigargin (100 nM) stimulated either a rapid (within 16 +/- 2 s) transient increase in [Ca2+]i or a slowly (99 +/- 20 s) developing and sustained increase in [Ca2+]i. Both [Ca2+]i responses were concentration (0.001-1 microM)-dependent with an EC50 around 40 nM. The transient [Ca2+]i response occurred in the absence of extracellular Ca2+ and was unaffected by pretreating the cells with the Ca2+ channel blockers methoxyverapamil (50 microM) or lanthanum (1 mM). The plateau phase of the sustained [Ca2+]i response returned to resting level in the absence of extracellular Ca2+, but remained elevated in the presence of methoxyverapamil (50 microM) or lanthanum (1 mM). Despite its ability to cause transient or prolonged increases in [Ca2+]i, thapsigargin (0.001-1 microM) did not affect basal or luteinizing hormone-stimulated progesterone production by chicken granulosa cells.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0143-4160
pubmed:author
pubmed:issnType
Print
pubmed:volume
13
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
263-71
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1992
pubmed:articleTitle
Thapsigargin increases cytoplasmic free Ca2+ without influencing steroidogenesis in chicken granulosa cells.
pubmed:affiliation
Department of Obstetrics and Gynecology and Physiology, University of Ottawa, Ontario, Canada.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't