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.
Laboratory of Theriogenology, National Institute of Animal Health, Tsukuba, Ibaraki 305-0856, Japan. kojiyos@niah.affrc.go.jp
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K
Yoshioka
C
C
Suzuki
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S
Iwamura
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