Aspects of follicular and oocyte maturation that affect the developmental potential of embryos

摘要: The ability to mature, be fertilized and finally develop into a viable embryo is acquired gradually by the oocyte during progressive differentiation throughout folliculogenesis. This process starts with growth first steps of follicular development. As close its final size, other modifications occur, less spectacular but at least as important in determining resulting accomplish reproductive purpose (developmental competence). These modifications, referred 'oocyte capacitation', are probably influenced follicle. proportion developmentally competent oocytes increases size. However, relationship between competence not very strict, since given may acquire any stage some examples functional disjunction size described. Follicular atresia impair acquisition competence, evidenced parallel study characteristics developmental potential their treated individually through vitro maturation, fertilization when experimentally induced large preovulatory follicles, remain competent, indicating that once acquired, it no longer sensitive atresia. Oocyte maturation represents only end this long validates preparation conferring ability. recent cloning experiments, cytoplasmic aspects crucial for competence. activated use complex media supplement (serum, fluid) defined allowed identification active factors (such epidermal factor, hormone, inhibin activin). differential models (follicular atresia, Booroola gene, prepubertal oocytes) will provide better understanding capacitation allow improvement methods which represent most limiting step production embryos mammals.