Fig. 4. Effect of inhibition of protein synthesis on development of betaine transport activity after egg activation. The rate of betaine transport was measured in freshly obtained mouse MII oocytes (MII 0 hr), MII oocytes maintained in culture for the entire period (MII 12 hr), Sr²⁺-activated oocytes 12 hours post-activation (Sr²⁺), and oocytes that were activated with 50 µg/ml cycloheximide. Bars with different letters are significantly different (P<0.05; ANOVA and Tukey-Kramer post-hoc test). Each bar represents the mean±s.e.m. of three independent measurements.