Skip Navigation


Hum. Reprod. Advance Access originally published online on June 21, 2006
Human Reproduction 2006 21(9):2228-2237; doi:10.1093/humrep/del184
This Article
Right arrow Full Text Freely available
Right arrow FREE Full Text (PDF ) Freely available
Right arrow All Versions of this Article:
21/9/2228    most recent
del184v1
Right arrow Submit a response
Right arrow Alert me when this article is cited
Right arrow Alert me when eLetters are posted
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrow Search for citing articles in:
ISI Web of Science (1)
Right arrowRequest Permissions
Google Scholar
Right arrow Articles by Ptak, G.
Right arrow Articles by Loi, P.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Ptak, G.
Right arrow Articles by Loi, P.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

© The Author 2006. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oxfordjournals.org

Developmental and functional evidence of nuclear immaturity in prepubertal oocytes

Grazyna Ptak1,2,3, Kazutsugu Matsukawa1, Chiara Palmieri1, Leonardo Della Salda1, Pier Augusto Scapolo1 and Pasqualino Loi1

1 Department of Comparative Biomedical Sciences, University of Teramo, Teramo, Italy and 2 Department of Animal Reproduction, University of Agriculture, Krakow, Poland

3 To whom correspondence should be addressed at: Department of Comparative Biomedical Sciences, Piazza A. Moro, 45, Teramo 64100, Italy. E-mail: gptak{at}unite.it

BACKGROUND: The nuclear compartment has been proposed as responsible for the developmental arrest of prepubertal mouse oocytes while the studies on prepubertal sheep and cow oocyte model suggested the cytoplasm immaturity accounts for this failure. METHODS: The apparent disagreement on the causes of developmental defects between these two species prompted us to study: (i) follicular and oocyte growth allometry in lambs, (ii) oocyte compartment (nucleus versus cytoplasm) responsible for developmental failure by nucleus exchange between lamb and adult sheep oocytes, (iii) nucleolar features of prepubertal oocytes by ultrastructural observation and (iv) in vivo developmental survey of prepubertally derived embryos. RESULTS: The oocyte growth inside the follicle is asynchronous during prepuberty. The nuclear transfer revealed that the lamb nucleus was responsible for developmental failure. Immature fibrillogranular structure of the nucleolus has been revealed in small lamb oocytes and also in a few adult-size lamb oocytes. Studies in vivo revealed a high occurrence of developmental arrest of prepubertal derived fetuses, which we have attributed to the low genome-wide methylation detected in prepubertal oocytes. CONCLUSIONS: Our studies have indicated incomplete nuclear maturation of prepubertal gamete. The implication of this finding suggests caution when the strategy of rescue of prepubertal oocytes for assisted fertilization is considered such as in the case of therapeutic treatment which precludes the maintenance of fertility of sexually immature patients.

Key words: developmental arrest/methylation/nuclear immaturity/oocyte/prepuberty


Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?




Disclaimer:
Please note that abstracts for content published before 1996 were created through digital scanning and may therefore not exactly replicate the text of the original print issues. All efforts have been made to ensure accuracy, but the Publisher will not be held responsible for any remaining inaccuracies. If you require any further clarification, please contact our Customer Services Department.