Linked Life Data

11713220

Source:http://linkedlifedata.com/resource/pubmed/id/11713220

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
12
pubmed:dateCreated
2001-11-19
pubmed:abstractText
In virtually all studies with MA-10 cells, progesterone RIAs have been used to measure steroid synthesis. To test whether progesterone is a stable end product, we investigated the metabolism of added tritiated progesterone and pregnenolone in MA-10 cells over a period of 3 h. Steroids were then extracted, separated by HPLC, and identified by GC/MS. We found that more than 70% of radiolabeled steroids were converted to at least five different metabolites. A major metabolite (40%) was 5 alpha-pregnan-3 alpha or 3 beta-ol-20one. Similar studies, using radiolabeled T, demonstrated conversion to dihydrotestosterone and two forms of 5 alpha-androstane-diols. These data indicate the presence of active 5 alpha-reductase and 3 alpha- and/or 3 beta-hydroxysteroid dehydrogenase activities in MA-10 cells. Because these results suggest that progesterone is an unstable end product, to gauge the level of active metabolism, we incubated cells in the presence of inhibitors of pregnenolone metabolism and assessed pregnenolone levels by RIA. We discovered that basal levels of steroidogenesis in MA-10 cells were considerably higher than previously estimated. Moreover, dibutyryl cAMP-stimulated steroid production was linear over more than 13 h, in contrast to previous findings that measured progesterone levels. Other consequences of inaccurate assessment of steroidogenic activity in MA-10 cells because of the application of the progesterone assay are discussed.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0013-7227
pubmed:author
pubmed:issnType
Print
pubmed:volume
142
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
5236-42
pubmed:dateRevised
2010-11-18
pubmed:meshHeading
pubmed:year
2001
pubmed:articleTitle
Implications of progesterone metabolism in MA-10 cells for accurate measurement of the rate of steroidogenesis.
pubmed:affiliation
Department of Endocrinology and Reproduction, Erasmus University, 3000 DR Rotterdam, The Netherlands. rommerts@endov.fgg.eur.nl
pubmed:publicationType
Journal Article, Comparative Study, Research Support, U.S. Gov't, P.H.S.