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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
1-2
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pubmed:dateCreated |
1992-8-19
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pubmed:abstractText |
It is well known that the number of follicles in the mammalian ovary decreases with age. In light of previous data from this laboratory showing age-related alterations in the secretion and production of follicle-stimulating hormone (FSH) in rats by 5-6 months of age, one objective of the present study was to determine if alterations in FSH secretion were accompanied by changes in the number of antral follicles. A second objective of this study was to determine whether or not interruption of cyclic activity by continuous progesterone (P) treatment could decelerate age-associated changes in FSH secretion possibly by retarding the depletion of follicles through ovulation. For this study, one group of 4-day cycling, 7-week-old rats received one empty Silastic implant while another group received 3-40 mm implants containing 30 mm crystalline P. Implants were replaced every 2 weeks until the animals were 5 months old. Progesterone-implanted rats were acyclic during treatment exhibiting predominantly leukocytic vaginal smears. Regular 4-day cycles resumed when P implants were withdrawn (rats approximately 5-6-months-old). A group of 2-3-month-old untreated rats were used for comparison. As expected from our previous results, serum FSH levels at 1600 h on estrus were significantly higher in 5-6-month-old rats receiving empty capsules than in younger rats. Serum FSH concentrations measured in P-treated rats at this time also were significantly higher than levels of this gonadotropin measured in younger rats. Ovaries of older control and P-treated rats contained significantly fewer medium and large antral follicles (greater than 250 microns) than the ovaries of younger rats despite the curtailment of estrous cyclicity and ovulation by continuous P treatment. Interestingly, P treatment prevented the age-associated decrease in thymus weight. Taken together, the present observations suggest that a decrease in the number of growing follicles may be a factor contributing to early age-related alterations in FSH secretion. Furthermore, the prevention (at least temporarily) of age-related thymic involution by P treatment may be indicative of an interrelationship between thymic and reproductive aging.
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pubmed:grant | |
pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
IM
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pubmed:chemical | |
pubmed:status |
MEDLINE
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pubmed:month |
Jun
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pubmed:issn |
0047-6374
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:volume |
64
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
111-22
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pubmed:dateRevised |
2007-11-14
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pubmed:meshHeading |
pubmed-meshheading:1630151-Aging,
pubmed-meshheading:1630151-Animals,
pubmed-meshheading:1630151-Estrus,
pubmed-meshheading:1630151-Female,
pubmed-meshheading:1630151-Follicle Stimulating Hormone,
pubmed-meshheading:1630151-Organ Size,
pubmed-meshheading:1630151-Ovarian Follicle,
pubmed-meshheading:1630151-Progesterone,
pubmed-meshheading:1630151-Rats,
pubmed-meshheading:1630151-Rats, Inbred Strains,
pubmed-meshheading:1630151-Thymus Gland
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pubmed:year |
1992
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pubmed:articleTitle |
Correlation of age-associated increases in follicle stimulating hormone secretion with decreases in antral follicles: failure of progesterone-induced acyclicity to prevent these changes.
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pubmed:affiliation |
Department of Physiology, University of Texas Health Science Center, San Antonio 78284.
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pubmed:publicationType |
Journal Article,
Research Support, U.S. Gov't, P.H.S.
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