abstract
- This study was designed to investigate whether the polyamines spermine, spermidine and putrescine can prevent the arrest of development of in-vitro fertilized murine oocytes from CD1 strain mice. Development in M16 or Brinster's medium with or without polyamine supplementation was assessed and the ability of blastocysts to attach and grow out on laminin was compared with in-vivo-generated embryo blastocysts. Oocytes from old (20 weeks) females showed lower rates of fertilization and subsequent development in comparison with oocytes from young (6-8 weeks old) females, but in both cases < 5% of in-vitro fertilized oocytes achieved the blastocyst stage. In-vitro fertilized young oocytes showed enhanced development to the blastocyst stage with the addition of the polyamine putrescine, although lesser enhancement was seen with spermine and spermidine; this effect was only evident when the oocytes were grown in Brinster's medium, reflecting the need for a particular set of culture conditions for growth-enhancing agents to be effective. Blastocysts generated in putrescine-supplemented Brinster's medium were able to implant on laminin-coated surfaces in vitro and to respond to the cytokines colony-stimulating factor-1, epidermal growth factor and platelet-derived growth factor with increased trophoblast outgrowth to a greater degree than in-vivo-generated blastocysts. Murine in-vitro fertilized embryo development was not enhanced by co-culture with Vero cells. Putrescine was the most effective polyamine, enhancing the in-vitro fertilized oocyte development to blastocysts in a permissive environment.