Mouse oocyte maturation in vitro at a low concentration of pyruvate in the culture medium

Mouse oocytes isolated from antrum--containing follicles were cultivated for 17-19 hours in the media with different concentrations of pyruvate. Decrease of pyruvate concentration down to 0.03 mM significantly increased the number of oocytes with intact germinal vesicles. However, in 50% of oocytes desintegration of nuclear membrane and condensation of chromosomes occurred even at a concentration of 0.02 mM.