Document Detail

Effect of RU486 on ovarian progesterone production at pro-oestrus and during pregnancy: a possible dual regulation of the biosynthesis of progesterone.
MedLine Citation:
PMID:  7861391     Owner:  NLM     Status:  MEDLINE    
Changes in progesterone production were analysed after intrabursal ovarian administration of the antiprogesterone RU486, mifepristone, in rats at pro-oestrus and during pregnancy. RU486 was administered at 09:00-10:00 h and serum progesterone was measured 8 h after treatment, except for those on days 3 and 12 of pregnancy when the steroid was measured 4, 8 and 24 h later. RU486 stimulates progesterone production on the day of pro-oestrus and on days 3-5 and 15-20 of pregnancy. Conversely, treatment with the antiprogestagen inhibits progesterone production on days 7-14 of gestation. The inhibition (day 12) or stimulation (day 19) of progesterone production induced by RU486 could be correlated with the simultaneous inhibition or stimulation of 3 beta-hydroxysteroid dehydrogenase (3 beta-HSD) activity observed in corpora lutea. A similar effect on 3 beta-HSD activity in corpora lutea was obtained by intrabursal ovarian administration of a specific progesterone antibody, indicating that the effect of RU486 is exerted through its antiprogesterone action. On the day of pro-oestrus and during early pregnancy the intrabursal ovarian injection of RU486 did not modify serum prolactin and LH concentrations, demonstrating that the antiprogesterone did not have a central action. The stimulatory action of RU486 on progesterone production on days 3 and 5 of pregnancy shifted to an inhibitory effect on progesterone production on day 7. Oestradiol treatment on day 6 of pregnancy reversed the effect of RU486 on progesterone production on day 7, inducing a response similar to that obtained on days 3 and 5 of gestation.(ABSTRACT TRUNCATED AT 250 WORDS)
C M Telleria; R P Deis
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Journal of reproduction and fertility     Volume:  102     ISSN:  0022-4251     ISO Abbreviation:  J. Reprod. Fertil.     Publication Date:  1994 Nov 
Date Detail:
Created Date:  1995-03-23     Completed Date:  1995-03-23     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  0376367     Medline TA:  J Reprod Fertil     Country:  ENGLAND    
Other Details:
Languages:  eng     Pagination:  379-84     Citation Subset:  IM    
Laboratorio de Reproducción y Lactancia, CRICYT-CONICET, Mendoza, Argentina.
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MeSH Terms
3-Hydroxysteroid Dehydrogenases / metabolism
Corpus Luteum / enzymology
Estradiol / pharmacology
Luteinizing Hormone / blood
Mifepristone / pharmacology*
Ovary / drug effects,  metabolism*
Progesterone / biosynthesis*,  blood
Prolactin / blood
Rats, Wistar
Stimulation, Chemical
Tamoxifen / pharmacology
Reg. No./Substance:
10540-29-1/Tamoxifen; 50-28-2/Estradiol; 57-83-0/Progesterone; 84371-65-3/Mifepristone; 9002-62-4/Prolactin; 9002-67-9/Luteinizing Hormone; EC 1.1.-/3-Hydroxysteroid Dehydrogenases

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

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