期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1999
卷号：96
期号：18
页码：10501-10506
DOI：10.1073/pnas.96.18.10501
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Female mice lacking the gene encoding the prostaglandin (PG) E2 receptor subtype EP2 (EP2-/-) become pregnant and deliver their pups at term, but with a much reduced litter size. A decrease in ovulation number and a much reduced fertilization rate were observed in EP2-/- females without difference of the uterus to support implantation of wild-type embryos. Treatment with gonadotropins induced EP2 mRNA expression in the cumulus cells of ovarian follicles of wild-type mice. The immature cumuli oophori from wild-type mice expanded in vitro in response to both follicle-stimulating hormone and PGE2, but the response to PGE2 was absent in those from EP2-/- mice. Cumulus expansion proceeded normally in preovulatory follicles but became abortive in a number of ovulated complexes in EP2-/- mice, indicating that EP2 is involved in cumulus expansion in the oviduct in vivo. No difference in the fertilization rate between wild-type and EP2-/- mice was found in in vitro studies using cumulus-free oocytes. These results indicate that PGE2 cooperates with gonadotropin to complete cumulus expansion for successful fertilization.
