Source:http://linkedlifedata.com/resource/pubmed/id/12814345
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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
1
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pubmed:dateCreated |
2003-6-19
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pubmed:abstractText |
The decline in pulsatile LH secretion and pituitary responsiveness to GnRH as pregnancy advances may be due to non-steroidal factors secreted by the ovine corpus luteum of pregnancy. Corpora lutea from ten ewes on days 70-80 of gestation were homogenized, charcoal-treated and, together with charcoal-treated follicular fluid from superovulated women, were subjected to inhibin immunoaffinity chromatography, reducing dimeric inhibin A and B by >90% and abolishing inhibin bioactivity. These preparations were investigated using cultures of rat pituitary cells. GnRH-induced LH and FSH secretion in vitro was reduced by ovine corpus luteum extract and human follicular fluid by 47+/-5% and 42+/-5% of control LH and by 37+/-5% and 50+/-10% of control FSH, respectively (P<0.001). Extracts prepared from corpora lutea and placentae that were collected on days 50, 90 and 120 of pregnancy (five ewes per stage of pregnancy) showed increased GnRH-induced LH-suppressing bioactivity, particularly in the case of the placental extracts, with a threefold increase in activity. When partially purified by pseudochromatofocusing, GnRH-induced LH-suppressing bioactivity in extracts of ovine corpora lutea was identified at pH 5.40 and 5.77. Although these values are similar to published gonadotrophin surge-attenuating factor (GnSAF) bioactivity pI values, a GnSAF-blocking antiserum had no consistent effect on ovine corpus luteum extract GnRH-induced LH-suppressing bioactivity. It was concluded that the ovine corpus luteum of pregnancy contains a non-steroidal, non-inhibin factor, probably not GnSAF, that has the ability to reduce pituitary responsiveness to GnRH in vitro.
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pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
IM
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pubmed:chemical |
http://linkedlifedata.com/resource/pubmed/chemical/Follicle Stimulating Hormone,
http://linkedlifedata.com/resource/pubmed/chemical/Gonadal Hormones,
http://linkedlifedata.com/resource/pubmed/chemical/Gonadotropin-Releasing Hormone,
http://linkedlifedata.com/resource/pubmed/chemical/Immune Sera,
http://linkedlifedata.com/resource/pubmed/chemical/Inhibins,
http://linkedlifedata.com/resource/pubmed/chemical/Luteinizing Hormone,
http://linkedlifedata.com/resource/pubmed/chemical/Proteins,
http://linkedlifedata.com/resource/pubmed/chemical/attenuin
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pubmed:status |
MEDLINE
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pubmed:month |
Jul
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pubmed:issn |
1470-1626
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:volume |
126
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
35-42
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pubmed:dateRevised |
2006-11-15
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pubmed:meshHeading |
pubmed-meshheading:12814345-Animals,
pubmed-meshheading:12814345-Cells, Cultured,
pubmed-meshheading:12814345-Corpus Luteum,
pubmed-meshheading:12814345-Depression, Chemical,
pubmed-meshheading:12814345-Female,
pubmed-meshheading:12814345-Follicle Stimulating Hormone,
pubmed-meshheading:12814345-Follicular Fluid,
pubmed-meshheading:12814345-Gonadal Hormones,
pubmed-meshheading:12814345-Gonadotropin-Releasing Hormone,
pubmed-meshheading:12814345-Humans,
pubmed-meshheading:12814345-Immune Sera,
pubmed-meshheading:12814345-Inhibins,
pubmed-meshheading:12814345-Luteinizing Hormone,
pubmed-meshheading:12814345-Pituitary Gland,
pubmed-meshheading:12814345-Placenta,
pubmed-meshheading:12814345-Pregnancy,
pubmed-meshheading:12814345-Pregnancy, Animal,
pubmed-meshheading:12814345-Proteins,
pubmed-meshheading:12814345-Rats,
pubmed-meshheading:12814345-Rats, Sprague-Dawley,
pubmed-meshheading:12814345-Sheep
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pubmed:year |
2003
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pubmed:articleTitle |
Demonstration of a non-steroidal, non-inhibin factor in the ovine corpus luteum of pregnancy that reduces pituitary responsiveness to GnRH-induced LH secretion in vitro.
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pubmed:affiliation |
Department of Obstetrics and Gynaecology, University of Aberdeen, Aberdeen AB25 2ZD, UK. p.a.fowler@abdn.ac.uk
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pubmed:publicationType |
Journal Article,
Research Support, Non-U.S. Gov't
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