Recently it was also reported that epidermal growth factor or coculture of pig oocytes with follicle shell pieces improved cytoplasmic maturation of pig oocytes by improving male pro-nuclear formation and subsequent embryo development. In the present study, we used an in vitro system that results in more than 30% of oocytes matured and inseminated to develop to blastocysts. It seems that improved oocyte maturation conditions have improved cytoplasmic maturation and increased the rate of blastocyst formation but have not significantly increased the cell number in blastocysts. Previous studies in pigs clearly indicated that intracellular glutathione was an important factor affecting embryo development. buy yasmin online
Glutathione has been found to regulate several important cellular functions, such as maintenance of cell and membrane integrity and redox status, regulation of protein and DNA synthesis, modulation of protein folding, and participation as a cofactor for various enzyme reactions or as a protector of the cell against oxidative stress. As mentioned above, the latter may be more important during embryo development under in vitro conditions. After fertilization, intracellular glutathione concentration decreases significantly, and the embryos do not have the ability to synthesize glutathione until the blastocyst stage; thus the embryos may be exposed to conditions with a high concentration of ROS.