EXPERIMENTAL STUDIES ON INVITRO MATURATION OF PORCINE OOCYTES .2. EFFECTS OF ESTRADIOL-17-BETA AND PROGESTERONE

The simple compounded semi-defined Whitten's medium was supplemented with estradiol-17beta and progesterone to examine whether they influence the nuclear maturation of porcine cumulus-oocyte complexes. Addition of estradiol-17beta at concentrations of 1.0 mug/ml and 10.0 mug/ml significantly inhibited the nuclear maturation in comparison to the control group. No significant inhibition of estradiol-17beta was observed at concentration of 0.1 mug/ml with respect to the control. After addition of synchronous or subsequent (12 h after the incubation with estradiol-17beta) supplementation of progesterone at concentration of 1 mug/ml, maturation rates were as high as control. So progesterone overcame the inhibitory effect of estradiol-17beta.