Bovine activin A does not affect the in vitro maturation of bovine oocytes.
The effect of recombinant bovine activin A on the in vitro maturation of bovine oocytes was investigated. Culture of cumulus enclosed bovine oocytes in the presence of activin at the concentration of 100 or 500 ng/ml did not change the proportion of oocytes in which germinal vesicle breakdown had occurred at 4 and 7 h after the onset of culture. Activin had also no effect on the progression of maturation to the M II stage. The transient inhibition of germinal vesicle breakdown by 10 mM dibutyryl cyclic AMP was not affected by the addition of activin A at the onset of culture. Radiolabeling with 35S-methionine at 4 h and at 18 h after culture in the presence or absence of activin A did not show any effect of activin either on the total incorporation of radiolabel into acid precipitable material or on the protein synthesis patterns obtained after SDS-PAGE.
Van Tol
H T
HT
Department of Herd Health and Reproduction, Faculty of Veterinary Medicine, University of Utrecht, Utrecht, Netherlands.
de Loos
F A
FA
Vanderstichele
H M
HM
Bevers
M M
MM