Linked Life Data

9408709

Source:http://linkedlifedata.com/resource/pubmed/id/9408709

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1998-2-19
pubmed:abstractText
Accumulated evidence indicates that the antigestagen mifepristone affects the reproductive axis acting on hypothalamic, pituitary, ovarian, and uterine tissues. The purpose of this study was to further investigate which reproductive functions are impaired by the antagonist, critically compromising the reproductive process, leading to unsuccessful pregnancy. Circulating pituitary and ovarian hormones, sexual receptivity, ovulation, and implantation rates were studied in cycling rats receiving a single dose of mifepristone (1 or 10 mg/kg subcutaneously) at 12:00 proestrus, before luteinizing hormone (LH) stimulation of the ovulatory process. Mifepristone-treated rats had decreased preovulatory surges of LH and prolactin (PRL), and hypersecretion of LH, PRL, and progesterone at estrus. The sexual receptivity was dramatically affected by the antagonist as indicated by the profound decrease in the lordosis response evaluated on the night of proestrus. The number of ovulating animals and the number of oocytes recovered from the oviduct on the morning of estrus were not affected by mifepristone. The low number of rats that succeeded in mating with potent males became pregnant. However, they delivered an average of only two pups at parturition, indicating a failure in the implantation of the fertilized ova, as ovulation was not affected by the antagonist at the dose used. We conclude that a dramatic inhibition of the sexual receptivity and unsuccessful implantation, preceded by a reduction on LH and PRL secretion, are the major components leading to fertility impairment after a single dose of mifepristone administered before the preovulatory surge of LH.
pubmed:keyword
http://linkedlifedata.com/resource/pubmed/keyword/ARGENTINA, http://linkedlifedata.com/resource/pubmed/keyword/Americas, http://linkedlifedata.com/resource/pubmed/keyword/Animals, Laboratory, http://linkedlifedata.com/resource/pubmed/keyword/Biology, http://linkedlifedata.com/resource/pubmed/keyword/Clinical Research, http://linkedlifedata.com/resource/pubmed/keyword/Contraception, http://linkedlifedata.com/resource/pubmed/keyword/Contraception Research, http://linkedlifedata.com/resource/pubmed/keyword/Contraceptive Mode Of Action, http://linkedlifedata.com/resource/pubmed/keyword/Developing Countries, http://linkedlifedata.com/resource/pubmed/keyword/Endocrine System, http://linkedlifedata.com/resource/pubmed/keyword/Family Planning, http://linkedlifedata.com/resource/pubmed/keyword/Gonadotropins, http://linkedlifedata.com/resource/pubmed/keyword/Gonadotropins, Pituitary, http://linkedlifedata.com/resource/pubmed/keyword/Hormone Antagonists, http://linkedlifedata.com/resource/pubmed/keyword/Hormones, http://linkedlifedata.com/resource/pubmed/keyword/Implantation Suppression, http://linkedlifedata.com/resource/pubmed/keyword/Latin America, http://linkedlifedata.com/resource/pubmed/keyword/Luteinizing Hormone, http://linkedlifedata.com/resource/pubmed/keyword/Ovulation, http://linkedlifedata.com/resource/pubmed/keyword/Ovulation Suppression, http://linkedlifedata.com/resource/pubmed/keyword/PROLACTIN, http://linkedlifedata.com/resource/pubmed/keyword/Physiology, http://linkedlifedata.com/resource/pubmed/keyword/Pituitary Hormones, http://linkedlifedata.com/resource/pubmed/keyword/Reproduction, http://linkedlifedata.com/resource/pubmed/keyword/Research Methodology, http://linkedlifedata.com/resource/pubmed/keyword/Research Report, http://linkedlifedata.com/resource/pubmed/keyword/Ru-486--administraction and dosage, http://linkedlifedata.com/resource/pubmed/keyword/Ru-486--pharmacodynamics, http://linkedlifedata.com/resource/pubmed/keyword/South America
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0010-7824
pubmed:author
pubmed:issnType
Print
pubmed:volume
56
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
267-74
pubmed:dateRevised
2006-11-15
pubmed:otherAbstract
PIP: Mifepristone has been demonstrated to act on hypothalamic, pituitary, ovarian, and uterine tissue. To further investigate impairments in reproductive function triggered by this antagonist, circulating pituitary and ovarian hormones, sexual receptivity, ovulation, and implantation rates were studied in cycling Wistar rats receiving a single dose (1 or 10 mg/kg subcutaneously) of mifepristone at 12:00 proestrus, before luteinizing hormone (LH) stimulation of the ovulatory process. Treated rats had decreased preovulatory LH and prolactin (PRL) surges and hypersecretion of LH, PRL, and progesterone as estrus. A profound decrease in the lordosis response on the night of proestrus indicated a dramatic effect on sexual receptivity. There was no affect on the number of ovulating animals and the number of oocytes recovered from the oviduct on the morning of estrus. The few rats who succeeded in mating with potent males became pregnant, but they delivered an average of only two pups, indicating a failure in the implantation of the fertilized ova. These findings suggest that the dramatic inhibition of sexual receptivity and unsuccessful implantation, preceded by a reduction in LH and PRL secretion, are the major factors producing fertility impairment after a single dose of mifepristone before the preovulatory LH surge. factors such as smoking and parity.
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
Fertility impairment after mifepristone treatment to rats at proestrus. Actions on the hypothalamic-hypophyseal-ovarian axis.
pubmed:affiliation
Laboratorio de Reproducción y Lactancia, Consejo Nacional de Investigaciones Científicas (LARLAC-CONICET), Mendoza, Argentina. CarlosMT@uic.edu
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't