Figure 7

Time-dependent effect of protein phosphatase 1/2A inhibition with okadaic acid on oocyte maturation. COC were cultured in okadaic acid-supplemented medium for different times followed by culture in inhibitor-free medium for up to a total of 12 (A) or 24 (B) hours of IVM; nuclear status was then assessed. Each column represents the mean percentages of oocytes in GV arrest (open bars), intermediate stage (grey bars) and mature stage (closed bars) ± SEM of at least three replicates. The mean percentage of oocytes that displayed condensed scattered chromatin is presented (hatched bars) and is included in the intermediate stage percentage. The number of oocytes per treatment is indicated under each bar. Statistical analysis by ANOVA showed that the treatments had significant effects (P < 0.0001). Asterisks indicate significant differences (P < 0.01) from control according to the Bonferroni post hoc test.