Activin A and follistatin regulate developmental competence of In vitro-produced bovine embryos.
The effects of activin A and/or follistatin on the development of bovine embryos were investigated. Presumptive zygotes matured and fertilized in vitro were cultured in a chemically defined medium (modified synthetic oviduct fluid medium; mSOF). Addition of 1-100 ng/ml of activin A to mSOF significantly increased the percentage of zygotes that developed to morulae and blastocysts (48-54% and 31-41%, respectively) compared with no addition (41% and 25%, respectively). In contrast, addition of 1-100 ng/ml follistatin significantly reduced the percentage of zygotes developing to morulae and blastocysts (29-31% and 17-20%, respectively) compared with no addition (41% and 28%, respectively). In a culture with 10 ng/ml of activin A, supplementation with the same concentration of follistatin neutralized the positive effect of activin A, while supplementation with 100 ng/ml of follistatin reduced the percentage of zygotes that developed. The total cell numbers in morulae and blastocysts were not affected by the addition of activin A and/or follistatin. The development-enhancing effects of activin A and the development-impeding effects of follistatin were observed when embryos were exposed to activin A or follistatin at a concentration of 10 ng/ml prior to the 9- to 16-cell stage. These results suggest that activin A and follistatin may affect bovine embryos until the third cell cycle and may play important roles in regulation of the developmental competence of bovine embryos.
Yoshioka
K
K
Laboratory of Theriogenology, National Institute of Animal Health, Tsukuba, Ibaraki 305-0856, Japan. kojiyos@niah.affrc.go.jp
Suzuki
C
C
Iwamura
S
S
D028341:Activins; D000818:Animals; D001755:Blastocyst / Q000166:cytology; D001826:Body Fluids; D002417:Cattle; D002452:Cell Count; D003470:Culture Media; D046508:Culture Techniques; D005314:Embryonic and Fetal Development; D005187:Fallopian Tubes / Q000378:metabolism; D005260:Female; D005307:Fertilization in Vitro; D038681:Follistatin; D006023:Glycoproteins / Q000008:administration & dosage / Q000494:pharmacology*; D006133:Growth Substances / Q000494:pharmacology*; D007265:Inhibins / Q000008:administration & dosage / Q000494:pharmacology*; D009028:Morula / Q000166:cytology
D003470:Culture Media; D038681:Follistatin; D006023:Glycoproteins; D006133:Growth Substances; D028341:Activins; D007265:Inhibins