Linked Life Data

15798021

Source:http://linkedlifedata.com/resource/pubmed/id/15798021

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2005-3-30
pubmed:abstractText
Heat stress inhibits ovarian follicular development in mammalian species. We hypothesized that heat stress inhibits the function of follicular granulosa cells and suppresses follicular development. To test this, immature female rats were injected with pregnant mare serum gonadotropin (PMSG) at 48 h after the start of temperature treatment (control: 25 degrees C, 50% RH; heat stress: 35 degrees C, 70% Relative Humidity). The ovaries and granulosa cells of follicles at different developmental stages were analyzed for gonadotropin receptor levels and aromatase activity; estradiol levels were measured in follicular fluid. Before injection, heat stress diminished only the amount of FSH receptor on granulosa cells of antral follicles. During PMSG-stimulated follicular development, heat stress strongly inhibited gonadotropin receptor levels and aromatase activity in granulosa cells, and estradiol levels in the follicular fluid of early antral, antral and preovulatory follicles. To examine apoptosis and mRNA levels of bcl-2 and bax in granulosa cells, follicles harvested 48 h after PMSG injection were cultured in serum-free conditions. Heat-stressed granulosa cells showed a time-dependent increase in apoptosis. The bcl-2 mRNA levels were similar in control and heat-stressed granulosa cells; bax mRNA levels were increased in heat-stressed granulosa cells. According to these results, heat stress inhibits expression of gonadotropin receptors in granulosa cells and attenuates estrogenic activity of growing follicles, granulosa cells of heat-stressed follicles are susceptible to apoptosis, and the bcl2/bax system is not associated with heat-stress-induced apoptosis of granulosa cells. Our study suggests that decreased numbers and function of granulosa cells may cause ovarian dysfunction in domestic animals in summer.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
1470-1626
pubmed:author
pubmed:issnType
Print
pubmed:volume
129
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
463-72
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed-meshheading:15798021-Animals, pubmed-meshheading:15798021-Apoptosis, pubmed-meshheading:15798021-Cell Culture Techniques, pubmed-meshheading:15798021-Estradiol, pubmed-meshheading:15798021-Female, pubmed-meshheading:15798021-Follicular Fluid, pubmed-meshheading:15798021-Genes, bcl-2, pubmed-meshheading:15798021-Gonadotropins, Equine, pubmed-meshheading:15798021-Granulosa Cells, pubmed-meshheading:15798021-Hot Temperature, pubmed-meshheading:15798021-Protein Binding, pubmed-meshheading:15798021-Proto-Oncogene Proteins c-bcl-2, pubmed-meshheading:15798021-RNA, Messenger, pubmed-meshheading:15798021-Rats, pubmed-meshheading:15798021-Rats, Wistar, pubmed-meshheading:15798021-Receptors, FSH, pubmed-meshheading:15798021-Receptors, Gonadotropin, pubmed-meshheading:15798021-Receptors, LH, pubmed-meshheading:15798021-Reverse Transcriptase Polymerase Chain Reaction, pubmed-meshheading:15798021-bcl-2-Associated X Protein
pubmed:year
2005
pubmed:articleTitle
Heat stress diminishes gonadotropin receptor expression and enhances susceptibility to apoptosis of rat granulosa cells.
pubmed:affiliation
Institute of Agriculture and Forestry, University of Tsukuba, Tsukuba, Ibaraki 305-8572, Japan.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't