Document Detail

Hormonal and cellular interactions in follicular steroid biosynthesis by the sheep ovary.
MedLine Citation:
PMID:  6300384     Owner:  NLM     Status:  MEDLINE    
Studies of isolated cell types from sheep follicles revealed several functional changes which occur during follicular maturation. Cyclic AMP production by granulosa cells from the smallest follicles studied (1-3 mm diameter) was stimulated by FSH but not by hCG, suggesting functional FSH receptors at this early stage of differentiation. Medium-sized follicles (4-6 mm) responded to both FSH and hCG. Granulosa cells were unable to synthesize androgens, but readily converted exogenous testosterone to oestradiol-17 beta. This conversion occurred to a limited extent in the cells from the smallest follicles, but was much greater in medium and large (greater than 6 mm) follicles. Oestradiol production by theca preparations from small follicles was barely detectable, but increased markedly with increasing follicle size. Androgen (androstenedione and testosterone) production by theca preparations was stimulated by hCG. This stimulation was short-lived, and levels declined to below control values after 6 h of culture. This decline could not be prevented by addition of cyclic AMP. The presence of granulosa cells with thecal preparations (i.e. follicle wall tissue) enhanced production of androgen by the theca, the effect being more marked for testosterone than for androstenedione. In-vivo studies in which granulosa cells and follicular fluid were removed during the preovulatory period suggested that granulosa cells and/or follicular fluid contributed to the oestradiol secreted into the ovarian vein during this period, but did not exclude a significant contribution by the theca as well.
D T Armstrong; T J Weiss; G Selstam; R F Seamark
Related Documents :
9678334 - An analysis of meiotic pairing in trisomy 21 oocytes using fluorescent in situ hybridiz...
3476484 - Corpus luteum function following spontaneous or prostaglandin-induced estrus in brahman...
6794554 - Hormonal correlates of follicular development in the human ovary.
9701794 - Membrane-bound carboxypeptidase-m is expressed on human ovarian follicles and corpora l...
2318264 - Effects of cell heterogeneity on production of polypeptide growth factors and mesoderm-...
20300194 - Btg interacts with retinoblastoma to control cell fate in dictyostelium.
Publication Detail:
Type:  Comparative Study; Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Journal of reproduction and fertility. Supplement     Volume:  30     ISSN:  0449-3087     ISO Abbreviation:  J. Reprod. Fertil. Suppl.     Publication Date:  1981  
Date Detail:
Created Date:  1983-05-27     Completed Date:  1983-05-27     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  0225652     Medline TA:  J Reprod Fertil Suppl     Country:  ENGLAND    
Other Details:
Languages:  eng     Pagination:  143-54     Citation Subset:  IM    
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Androgens / biosynthesis*
Bucladesine / pharmacology
Chorionic Gonadotropin / pharmacology
Culture Techniques
Cyclic AMP / biosynthesis
Estradiol / biosynthesis*
Follicle Stimulating Hormone / pharmacology
Gonadotropins / pharmacology*
Granulosa Cells / metabolism
Ovarian Follicle / drug effects,  metabolism*
Sheep / metabolism*
Theca Cells / metabolism
Reg. No./Substance:
0/Androgens; 0/Chorionic Gonadotropin; 0/Gonadotropins; 362-74-3/Bucladesine; 50-28-2/Estradiol; 60-92-4/Cyclic AMP; 9002-68-0/Follicle Stimulating Hormone

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

Previous Document:  Gonadotrophic control of follicular development and function during the oestrous cycle of the ewe.
Next Document:  Comparison of the interaction of equine LH and human chorionic gonadotrophin to equine testicular re...