ISSN:
0148-7280
Keywords:
oocyte
;
in vitro maturation
;
blastocysts
;
sheep
;
Life and Medical Sciences
;
Cell & Developmental Biology
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Biology
Notes:
The hypothesis that follicle cells play a central role in endowing the oocyte with developmental competence during maturation has been tested in coculture studies. Oocytes and follicle cells in various combinations were cultured for 24 h with gonadotrophins and estrogen in a nonstatic culture system. Developmental competence was assessed by transfer of oocytes to inseminated receipient ewes followed by embryonic examination 12 days later or at parturition.Denuded and corona-enclosed oocytes resume meiosis in culture but remain immature and developmentally incompetent. By contrast, oocytes supported by the cumulus and underlying granulosa (cumulus-oocyte complexes) undergo full maturation and normal subsequent embryonic development (42.6% to embryos). Addition of supplementary follicle cells during culture (5 × 106 cells/ml medium) is without beneficial effect on denuded oocytes. However, supplementary cells confer competence on corona-enclosed oocytes (37% to embryos).A dual cellular requirement for full maturation involving both cell numbers and some direct cell-oocyte contact is highlighted by our experiments. The results demonstrate further that the nonstatic system provides a simple but reliable method of producing large numbers of fully matured oocytes for both research and clinical purposes.
Additional Material:
2 Tab.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/mrd.1120090211
