Parthenogenetic activation and subsequent development of rat oocytes in vitro

Studies were undertaken to determine whether electrical stimulation, or eth anol treatment alone or in combination with 6-dimethylaminopurine (6-DMAP) influenced the rate of parthenogenetic activation of rat oocytes. The perce ntages of activated oocytes with pronuclei (89-91%) and those developed to the two-cell stage (68-72%) were significantly higher after electrical stim ulation with direct current (DC) at 100 V/mm, 99 mu sec once or twice, than when other DC voltages (75, 150, and 200) were applied or when ethanol or 6-DMAP treatment was given alone. However, none of the activated oocytes de veloped beyond the four-cell stage. The percentages of activated oocytes wi th pronuclei (100%) that developed to the two-cell (100%), eight-cell (89%) and blastocyst stages (50%) were significantly higher when electrical stim ulation was followed by treatment with 2 mM 6-DMAP for 4 hr than when other combined procedures were applied. In conclusion, the results of the presen t study clearly showed that combined treatment of electrical stimulation or ethanol with 6-DMAP induces parthenogenetic activation and subsequent deve lopment of rat oocytes in vitro. Mol. Reprod. Dev. 61: 120-125, 2002. (C) 2 002 Wiley-Liss, Inc.